Merge branch 'develop' of github.com:matrix-org/synapse into babolivier/new_push_rules

261 files changed, 34424 insertions, 0 deletions

diff --git a/synapse/storage/databases/main/__init__.py b/synapse/storage/databases/main/__init__.py
new file mode 100644
index 0000000000..17fa470919
--- /dev/null
+++ b/synapse/storage/databases/main/__init__.py
@@ -0,0 +1,596 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import calendar
+import logging
+import time
+
+from synapse.api.constants import PresenceState
+from synapse.config.homeserver import HomeServerConfig
+from synapse.storage.database import DatabasePool
+from synapse.storage.engines import PostgresEngine
+from synapse.storage.util.id_generators import (
+    IdGenerator,
+    MultiWriterIdGenerator,
+    StreamIdGenerator,
+)
+from synapse.util.caches.stream_change_cache import StreamChangeCache
+
+from .account_data import AccountDataStore
+from .appservice import ApplicationServiceStore, ApplicationServiceTransactionStore
+from .cache import CacheInvalidationWorkerStore
+from .censor_events import CensorEventsStore
+from .client_ips import ClientIpStore
+from .deviceinbox import DeviceInboxStore
+from .devices import DeviceStore
+from .directory import DirectoryStore
+from .e2e_room_keys import EndToEndRoomKeyStore
+from .end_to_end_keys import EndToEndKeyStore
+from .event_federation import EventFederationStore
+from .event_push_actions import EventPushActionsStore
+from .events_bg_updates import EventsBackgroundUpdatesStore
+from .filtering import FilteringStore
+from .group_server import GroupServerStore
+from .keys import KeyStore
+from .media_repository import MediaRepositoryStore
+from .metrics import ServerMetricsStore
+from .monthly_active_users import MonthlyActiveUsersStore
+from .openid import OpenIdStore
+from .presence import PresenceStore, UserPresenceState
+from .profile import ProfileStore
+from .purge_events import PurgeEventsStore
+from .push_rule import PushRuleStore
+from .pusher import PusherStore
+from .receipts import ReceiptsStore
+from .registration import RegistrationStore
+from .rejections import RejectionsStore
+from .relations import RelationsStore
+from .room import RoomStore
+from .roommember import RoomMemberStore
+from .search import SearchStore
+from .signatures import SignatureStore
+from .state import StateStore
+from .stats import StatsStore
+from .stream import StreamStore
+from .tags import TagsStore
+from .transactions import TransactionStore
+from .ui_auth import UIAuthStore
+from .user_directory import UserDirectoryStore
+from .user_erasure_store import UserErasureStore
+
+logger = logging.getLogger(__name__)
+
+
+class DataStore(
+    EventsBackgroundUpdatesStore,
+    RoomMemberStore,
+    RoomStore,
+    RegistrationStore,
+    StreamStore,
+    ProfileStore,
+    PresenceStore,
+    TransactionStore,
+    DirectoryStore,
+    KeyStore,
+    StateStore,
+    SignatureStore,
+    ApplicationServiceStore,
+    PurgeEventsStore,
+    EventFederationStore,
+    MediaRepositoryStore,
+    RejectionsStore,
+    FilteringStore,
+    PusherStore,
+    PushRuleStore,
+    ApplicationServiceTransactionStore,
+    ReceiptsStore,
+    EndToEndKeyStore,
+    EndToEndRoomKeyStore,
+    SearchStore,
+    TagsStore,
+    AccountDataStore,
+    EventPushActionsStore,
+    OpenIdStore,
+    ClientIpStore,
+    DeviceStore,
+    DeviceInboxStore,
+    UserDirectoryStore,
+    GroupServerStore,
+    UserErasureStore,
+    MonthlyActiveUsersStore,
+    StatsStore,
+    RelationsStore,
+    CensorEventsStore,
+    UIAuthStore,
+    CacheInvalidationWorkerStore,
+    ServerMetricsStore,
+):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        self.hs = hs
+        self._clock = hs.get_clock()
+        self.database_engine = database.engine
+
+        self._presence_id_gen = StreamIdGenerator(
+            db_conn, "presence_stream", "stream_id"
+        )
+        self._device_inbox_id_gen = StreamIdGenerator(
+            db_conn, "device_inbox", "stream_id"
+        )
+        self._public_room_id_gen = StreamIdGenerator(
+            db_conn, "public_room_list_stream", "stream_id"
+        )
+        self._device_list_id_gen = StreamIdGenerator(
+            db_conn,
+            "device_lists_stream",
+            "stream_id",
+            extra_tables=[
+                ("user_signature_stream", "stream_id"),
+                ("device_lists_outbound_pokes", "stream_id"),
+            ],
+        )
+        self._cross_signing_id_gen = StreamIdGenerator(
+            db_conn, "e2e_cross_signing_keys", "stream_id"
+        )
+
+        self._access_tokens_id_gen = IdGenerator(db_conn, "access_tokens", "id")
+        self._event_reports_id_gen = IdGenerator(db_conn, "event_reports", "id")
+        self._push_rule_id_gen = IdGenerator(db_conn, "push_rules", "id")
+        self._push_rules_enable_id_gen = IdGenerator(db_conn, "push_rules_enable", "id")
+        self._pushers_id_gen = StreamIdGenerator(
+            db_conn, "pushers", "id", extra_tables=[("deleted_pushers", "stream_id")]
+        )
+        self._group_updates_id_gen = StreamIdGenerator(
+            db_conn, "local_group_updates", "stream_id"
+        )
+
+        if isinstance(self.database_engine, PostgresEngine):
+            self._cache_id_gen = MultiWriterIdGenerator(
+                db_conn,
+                database,
+                instance_name="master",
+                table="cache_invalidation_stream_by_instance",
+                instance_column="instance_name",
+                id_column="stream_id",
+                sequence_name="cache_invalidation_stream_seq",
+            )
+        else:
+            self._cache_id_gen = None
+
+        super(DataStore, self).__init__(database, db_conn, hs)
+
+        self._presence_on_startup = self._get_active_presence(db_conn)
+
+        presence_cache_prefill, min_presence_val = self.db_pool.get_cache_dict(
+            db_conn,
+            "presence_stream",
+            entity_column="user_id",
+            stream_column="stream_id",
+            max_value=self._presence_id_gen.get_current_token(),
+        )
+        self.presence_stream_cache = StreamChangeCache(
+            "PresenceStreamChangeCache",
+            min_presence_val,
+            prefilled_cache=presence_cache_prefill,
+        )
+
+        max_device_inbox_id = self._device_inbox_id_gen.get_current_token()
+        device_inbox_prefill, min_device_inbox_id = self.db_pool.get_cache_dict(
+            db_conn,
+            "device_inbox",
+            entity_column="user_id",
+            stream_column="stream_id",
+            max_value=max_device_inbox_id,
+            limit=1000,
+        )
+        self._device_inbox_stream_cache = StreamChangeCache(
+            "DeviceInboxStreamChangeCache",
+            min_device_inbox_id,
+            prefilled_cache=device_inbox_prefill,
+        )
+        # The federation outbox and the local device inbox uses the same
+        # stream_id generator.
+        device_outbox_prefill, min_device_outbox_id = self.db_pool.get_cache_dict(
+            db_conn,
+            "device_federation_outbox",
+            entity_column="destination",
+            stream_column="stream_id",
+            max_value=max_device_inbox_id,
+            limit=1000,
+        )
+        self._device_federation_outbox_stream_cache = StreamChangeCache(
+            "DeviceFederationOutboxStreamChangeCache",
+            min_device_outbox_id,
+            prefilled_cache=device_outbox_prefill,
+        )
+
+        device_list_max = self._device_list_id_gen.get_current_token()
+        self._device_list_stream_cache = StreamChangeCache(
+            "DeviceListStreamChangeCache", device_list_max
+        )
+        self._user_signature_stream_cache = StreamChangeCache(
+            "UserSignatureStreamChangeCache", device_list_max
+        )
+        self._device_list_federation_stream_cache = StreamChangeCache(
+            "DeviceListFederationStreamChangeCache", device_list_max
+        )
+
+        events_max = self._stream_id_gen.get_current_token()
+        curr_state_delta_prefill, min_curr_state_delta_id = self.db_pool.get_cache_dict(
+            db_conn,
+            "current_state_delta_stream",
+            entity_column="room_id",
+            stream_column="stream_id",
+            max_value=events_max,  # As we share the stream id with events token
+            limit=1000,
+        )
+        self._curr_state_delta_stream_cache = StreamChangeCache(
+            "_curr_state_delta_stream_cache",
+            min_curr_state_delta_id,
+            prefilled_cache=curr_state_delta_prefill,
+        )
+
+        _group_updates_prefill, min_group_updates_id = self.db_pool.get_cache_dict(
+            db_conn,
+            "local_group_updates",
+            entity_column="user_id",
+            stream_column="stream_id",
+            max_value=self._group_updates_id_gen.get_current_token(),
+            limit=1000,
+        )
+        self._group_updates_stream_cache = StreamChangeCache(
+            "_group_updates_stream_cache",
+            min_group_updates_id,
+            prefilled_cache=_group_updates_prefill,
+        )
+
+        self._stream_order_on_start = self.get_room_max_stream_ordering()
+        self._min_stream_order_on_start = self.get_room_min_stream_ordering()
+
+        # Used in _generate_user_daily_visits to keep track of progress
+        self._last_user_visit_update = self._get_start_of_day()
+
+    def take_presence_startup_info(self):
+        active_on_startup = self._presence_on_startup
+        self._presence_on_startup = None
+        return active_on_startup
+
+    def _get_active_presence(self, db_conn):
+        """Fetch non-offline presence from the database so that we can register
+        the appropriate time outs.
+        """
+
+        sql = (
+            "SELECT user_id, state, last_active_ts, last_federation_update_ts,"
+            " last_user_sync_ts, status_msg, currently_active FROM presence_stream"
+            " WHERE state != ?"
+        )
+        sql = self.database_engine.convert_param_style(sql)
+
+        txn = db_conn.cursor()
+        txn.execute(sql, (PresenceState.OFFLINE,))
+        rows = self.db_pool.cursor_to_dict(txn)
+        txn.close()
+
+        for row in rows:
+            row["currently_active"] = bool(row["currently_active"])
+
+        return [UserPresenceState(**row) for row in rows]
+
+    def count_daily_users(self):
+        """
+        Counts the number of users who used this homeserver in the last 24 hours.
+        """
+        yesterday = int(self._clock.time_msec()) - (1000 * 60 * 60 * 24)
+        return self.db_pool.runInteraction(
+            "count_daily_users", self._count_users, yesterday
+        )
+
+    def count_monthly_users(self):
+        """
+        Counts the number of users who used this homeserver in the last 30 days.
+        Note this method is intended for phonehome metrics only and is different
+        from the mau figure in synapse.storage.monthly_active_users which,
+        amongst other things, includes a 3 day grace period before a user counts.
+        """
+        thirty_days_ago = int(self._clock.time_msec()) - (1000 * 60 * 60 * 24 * 30)
+        return self.db_pool.runInteraction(
+            "count_monthly_users", self._count_users, thirty_days_ago
+        )
+
+    def _count_users(self, txn, time_from):
+        """
+        Returns number of users seen in the past time_from period
+        """
+        sql = """
+            SELECT COALESCE(count(*), 0) FROM (
+                SELECT user_id FROM user_ips
+                WHERE last_seen > ?
+                GROUP BY user_id
+            ) u
+        """
+        txn.execute(sql, (time_from,))
+        (count,) = txn.fetchone()
+        return count
+
+    def count_r30_users(self):
+        """
+        Counts the number of 30 day retained users, defined as:-
+         * Users who have created their accounts more than 30 days ago
+         * Where last seen at most 30 days ago
+         * Where account creation and last_seen are > 30 days apart
+
+         Returns counts globaly for a given user as well as breaking
+         by platform
+        """
+
+        def _count_r30_users(txn):
+            thirty_days_in_secs = 86400 * 30
+            now = int(self._clock.time())
+            thirty_days_ago_in_secs = now - thirty_days_in_secs
+
+            sql = """
+                SELECT platform, COALESCE(count(*), 0) FROM (
+                     SELECT
+                        users.name, platform, users.creation_ts * 1000,
+                        MAX(uip.last_seen)
+                     FROM users
+                     INNER JOIN (
+                         SELECT
+                         user_id,
+                         last_seen,
+                         CASE
+                             WHEN user_agent LIKE '%%Android%%' THEN 'android'
+                             WHEN user_agent LIKE '%%iOS%%' THEN 'ios'
+                             WHEN user_agent LIKE '%%Electron%%' THEN 'electron'
+                             WHEN user_agent LIKE '%%Mozilla%%' THEN 'web'
+                             WHEN user_agent LIKE '%%Gecko%%' THEN 'web'
+                             ELSE 'unknown'
+                         END
+                         AS platform
+                         FROM user_ips
+                     ) uip
+                     ON users.name = uip.user_id
+                     AND users.appservice_id is NULL
+                     AND users.creation_ts < ?
+                     AND uip.last_seen/1000 > ?
+                     AND (uip.last_seen/1000) - users.creation_ts > 86400 * 30
+                     GROUP BY users.name, platform, users.creation_ts
+                ) u GROUP BY platform
+            """
+
+            results = {}
+            txn.execute(sql, (thirty_days_ago_in_secs, thirty_days_ago_in_secs))
+
+            for row in txn:
+                if row[0] == "unknown":
+                    pass
+                results[row[0]] = row[1]
+
+            sql = """
+                SELECT COALESCE(count(*), 0) FROM (
+                    SELECT users.name, users.creation_ts * 1000,
+                                                        MAX(uip.last_seen)
+                    FROM users
+                    INNER JOIN (
+                        SELECT
+                        user_id,
+                        last_seen
+                        FROM user_ips
+                    ) uip
+                    ON users.name = uip.user_id
+                    AND appservice_id is NULL
+                    AND users.creation_ts < ?
+                    AND uip.last_seen/1000 > ?
+                    AND (uip.last_seen/1000) - users.creation_ts > 86400 * 30
+                    GROUP BY users.name, users.creation_ts
+                ) u
+            """
+
+            txn.execute(sql, (thirty_days_ago_in_secs, thirty_days_ago_in_secs))
+
+            (count,) = txn.fetchone()
+            results["all"] = count
+
+            return results
+
+        return self.db_pool.runInteraction("count_r30_users", _count_r30_users)
+
+    def _get_start_of_day(self):
+        """
+        Returns millisecond unixtime for start of UTC day.
+        """
+        now = time.gmtime()
+        today_start = calendar.timegm((now.tm_year, now.tm_mon, now.tm_mday, 0, 0, 0))
+        return today_start * 1000
+
+    def generate_user_daily_visits(self):
+        """
+        Generates daily visit data for use in cohort/ retention analysis
+        """
+
+        def _generate_user_daily_visits(txn):
+            logger.info("Calling _generate_user_daily_visits")
+            today_start = self._get_start_of_day()
+            a_day_in_milliseconds = 24 * 60 * 60 * 1000
+            now = self.clock.time_msec()
+
+            sql = """
+                INSERT INTO user_daily_visits (user_id, device_id, timestamp)
+                    SELECT u.user_id, u.device_id, ?
+                    FROM user_ips AS u
+                    LEFT JOIN (
+                      SELECT user_id, device_id, timestamp FROM user_daily_visits
+                      WHERE timestamp = ?
+                    ) udv
+                    ON u.user_id = udv.user_id AND u.device_id=udv.device_id
+                    INNER JOIN users ON users.name=u.user_id
+                    WHERE last_seen > ? AND last_seen <= ?
+                    AND udv.timestamp IS NULL AND users.is_guest=0
+                    AND users.appservice_id IS NULL
+                    GROUP BY u.user_id, u.device_id
+            """
+
+            # This means that the day has rolled over but there could still
+            # be entries from the previous day. There is an edge case
+            # where if the user logs in at 23:59 and overwrites their
+            # last_seen at 00:01 then they will not be counted in the
+            # previous day's stats - it is important that the query is run
+            # often to minimise this case.
+            if today_start > self._last_user_visit_update:
+                yesterday_start = today_start - a_day_in_milliseconds
+                txn.execute(
+                    sql,
+                    (
+                        yesterday_start,
+                        yesterday_start,
+                        self._last_user_visit_update,
+                        today_start,
+                    ),
+                )
+                self._last_user_visit_update = today_start
+
+            txn.execute(
+                sql, (today_start, today_start, self._last_user_visit_update, now)
+            )
+            # Update _last_user_visit_update to now. The reason to do this
+            # rather just clamping to the beginning of the day is to limit
+            # the size of the join - meaning that the query can be run more
+            # frequently
+            self._last_user_visit_update = now
+
+        return self.db_pool.runInteraction(
+            "generate_user_daily_visits", _generate_user_daily_visits
+        )
+
+    def get_users(self):
+        """Function to retrieve a list of users in users table.
+
+        Args:
+        Returns:
+            defer.Deferred: resolves to list[dict[str, Any]]
+        """
+        return self.db_pool.simple_select_list(
+            table="users",
+            keyvalues={},
+            retcols=[
+                "name",
+                "password_hash",
+                "is_guest",
+                "admin",
+                "user_type",
+                "deactivated",
+            ],
+            desc="get_users",
+        )
+
+    def get_users_paginate(
+        self, start, limit, name=None, guests=True, deactivated=False
+    ):
+        """Function to retrieve a paginated list of users from
+        users list. This will return a json list of users and the
+        total number of users matching the filter criteria.
+
+        Args:
+            start (int): start number to begin the query from
+            limit (int): number of rows to retrieve
+            name (string): filter for user names
+            guests (bool): whether to in include guest users
+            deactivated (bool): whether to include deactivated users
+        Returns:
+            defer.Deferred: resolves to list[dict[str, Any]], int
+        """
+
+        def get_users_paginate_txn(txn):
+            filters = []
+            args = []
+
+            if name:
+                filters.append("name LIKE ?")
+                args.append("%" + name + "%")
+
+            if not guests:
+                filters.append("is_guest = 0")
+
+            if not deactivated:
+                filters.append("deactivated = 0")
+
+            where_clause = "WHERE " + " AND ".join(filters) if len(filters) > 0 else ""
+
+            sql = "SELECT COUNT(*) as total_users FROM users %s" % (where_clause)
+            txn.execute(sql, args)
+            count = txn.fetchone()[0]
+
+            args = [self.hs.config.server_name] + args + [limit, start]
+            sql = """
+                SELECT name, user_type, is_guest, admin, deactivated, displayname, avatar_url
+                FROM users as u
+                LEFT JOIN profiles AS p ON u.name = '@' || p.user_id || ':' || ?
+                {}
+                ORDER BY u.name LIMIT ? OFFSET ?
+                """.format(
+                where_clause
+            )
+            txn.execute(sql, args)
+            users = self.db_pool.cursor_to_dict(txn)
+            return users, count
+
+        return self.db_pool.runInteraction(
+            "get_users_paginate_txn", get_users_paginate_txn
+        )
+
+    def search_users(self, term):
+        """Function to search users list for one or more users with
+        the matched term.
+
+        Args:
+            term (str): search term
+            col (str): column to query term should be matched to
+        Returns:
+            defer.Deferred: resolves to list[dict[str, Any]]
+        """
+        return self.db_pool.simple_search_list(
+            table="users",
+            term=term,
+            col="name",
+            retcols=["name", "password_hash", "is_guest", "admin", "user_type"],
+            desc="search_users",
+        )
+
+
+def check_database_before_upgrade(cur, database_engine, config: HomeServerConfig):
+    """Called before upgrading an existing database to check that it is broadly sane
+    compared with the configuration.
+    """
+    domain = config.server_name
+
+    sql = database_engine.convert_param_style(
+        "SELECT COUNT(*) FROM users WHERE name NOT LIKE ?"
+    )
+    pat = "%:" + domain
+    cur.execute(sql, (pat,))
+    num_not_matching = cur.fetchall()[0][0]
+    if num_not_matching == 0:
+        return
+
+    raise Exception(
+        "Found users in database not native to %s!\n"
+        "You cannot changed a synapse server_name after it's been configured"
+        % (domain,)
+    )
+
+
+__all__ = ["DataStore", "check_database_before_upgrade"]
diff --git a/synapse/storage/databases/main/account_data.py b/synapse/storage/databases/main/account_data.py
new file mode 100644
index 0000000000..2193d8fdc5
--- /dev/null
+++ b/synapse/storage/databases/main/account_data.py
@@ -0,0 +1,430 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import abc
+import logging
+from typing import List, Tuple
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.storage.database import DatabasePool
+from synapse.storage.util.id_generators import StreamIdGenerator
+from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
+from synapse.util.caches.stream_change_cache import StreamChangeCache
+
+logger = logging.getLogger(__name__)
+
+
+class AccountDataWorkerStore(SQLBaseStore):
+    """This is an abstract base class where subclasses must implement
+    `get_max_account_data_stream_id` which can be called in the initializer.
+    """
+
+    # This ABCMeta metaclass ensures that we cannot be instantiated without
+    # the abstract methods being implemented.
+    __metaclass__ = abc.ABCMeta
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        account_max = self.get_max_account_data_stream_id()
+        self._account_data_stream_cache = StreamChangeCache(
+            "AccountDataAndTagsChangeCache", account_max
+        )
+
+        super(AccountDataWorkerStore, self).__init__(database, db_conn, hs)
+
+    @abc.abstractmethod
+    def get_max_account_data_stream_id(self):
+        """Get the current max stream ID for account data stream
+
+        Returns:
+            int
+        """
+        raise NotImplementedError()
+
+    @cached()
+    def get_account_data_for_user(self, user_id):
+        """Get all the client account_data for a user.
+
+        Args:
+            user_id(str): The user to get the account_data for.
+        Returns:
+            A deferred pair of a dict of global account_data and a dict
+            mapping from room_id string to per room account_data dicts.
+        """
+
+        def get_account_data_for_user_txn(txn):
+            rows = self.db_pool.simple_select_list_txn(
+                txn,
+                "account_data",
+                {"user_id": user_id},
+                ["account_data_type", "content"],
+            )
+
+            global_account_data = {
+                row["account_data_type"]: db_to_json(row["content"]) for row in rows
+            }
+
+            rows = self.db_pool.simple_select_list_txn(
+                txn,
+                "room_account_data",
+                {"user_id": user_id},
+                ["room_id", "account_data_type", "content"],
+            )
+
+            by_room = {}
+            for row in rows:
+                room_data = by_room.setdefault(row["room_id"], {})
+                room_data[row["account_data_type"]] = db_to_json(row["content"])
+
+            return global_account_data, by_room
+
+        return self.db_pool.runInteraction(
+            "get_account_data_for_user", get_account_data_for_user_txn
+        )
+
+    @cachedInlineCallbacks(num_args=2, max_entries=5000)
+    def get_global_account_data_by_type_for_user(self, data_type, user_id):
+        """
+        Returns:
+            Deferred: A dict
+        """
+        result = yield self.db_pool.simple_select_one_onecol(
+            table="account_data",
+            keyvalues={"user_id": user_id, "account_data_type": data_type},
+            retcol="content",
+            desc="get_global_account_data_by_type_for_user",
+            allow_none=True,
+        )
+
+        if result:
+            return db_to_json(result)
+        else:
+            return None
+
+    @cached(num_args=2)
+    def get_account_data_for_room(self, user_id, room_id):
+        """Get all the client account_data for a user for a room.
+
+        Args:
+            user_id(str): The user to get the account_data for.
+            room_id(str): The room to get the account_data for.
+        Returns:
+            A deferred dict of the room account_data
+        """
+
+        def get_account_data_for_room_txn(txn):
+            rows = self.db_pool.simple_select_list_txn(
+                txn,
+                "room_account_data",
+                {"user_id": user_id, "room_id": room_id},
+                ["account_data_type", "content"],
+            )
+
+            return {
+                row["account_data_type"]: db_to_json(row["content"]) for row in rows
+            }
+
+        return self.db_pool.runInteraction(
+            "get_account_data_for_room", get_account_data_for_room_txn
+        )
+
+    @cached(num_args=3, max_entries=5000)
+    def get_account_data_for_room_and_type(self, user_id, room_id, account_data_type):
+        """Get the client account_data of given type for a user for a room.
+
+        Args:
+            user_id(str): The user to get the account_data for.
+            room_id(str): The room to get the account_data for.
+            account_data_type (str): The account data type to get.
+        Returns:
+            A deferred of the room account_data for that type, or None if
+            there isn't any set.
+        """
+
+        def get_account_data_for_room_and_type_txn(txn):
+            content_json = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="room_account_data",
+                keyvalues={
+                    "user_id": user_id,
+                    "room_id": room_id,
+                    "account_data_type": account_data_type,
+                },
+                retcol="content",
+                allow_none=True,
+            )
+
+            return db_to_json(content_json) if content_json else None
+
+        return self.db_pool.runInteraction(
+            "get_account_data_for_room_and_type", get_account_data_for_room_and_type_txn
+        )
+
+    async def get_updated_global_account_data(
+        self, last_id: int, current_id: int, limit: int
+    ) -> List[Tuple[int, str, str]]:
+        """Get the global account_data that has changed, for the account_data stream
+
+        Args:
+            last_id: the last stream_id from the previous batch.
+            current_id: the maximum stream_id to return up to
+            limit: the maximum number of rows to return
+
+        Returns:
+            A list of tuples of stream_id int, user_id string,
+            and type string.
+        """
+        if last_id == current_id:
+            return []
+
+        def get_updated_global_account_data_txn(txn):
+            sql = (
+                "SELECT stream_id, user_id, account_data_type"
+                " FROM account_data WHERE ? < stream_id AND stream_id <= ?"
+                " ORDER BY stream_id ASC LIMIT ?"
+            )
+            txn.execute(sql, (last_id, current_id, limit))
+            return txn.fetchall()
+
+        return await self.db_pool.runInteraction(
+            "get_updated_global_account_data", get_updated_global_account_data_txn
+        )
+
+    async def get_updated_room_account_data(
+        self, last_id: int, current_id: int, limit: int
+    ) -> List[Tuple[int, str, str, str]]:
+        """Get the global account_data that has changed, for the account_data stream
+
+        Args:
+            last_id: the last stream_id from the previous batch.
+            current_id: the maximum stream_id to return up to
+            limit: the maximum number of rows to return
+
+        Returns:
+            A list of tuples of stream_id int, user_id string,
+            room_id string and type string.
+        """
+        if last_id == current_id:
+            return []
+
+        def get_updated_room_account_data_txn(txn):
+            sql = (
+                "SELECT stream_id, user_id, room_id, account_data_type"
+                " FROM room_account_data WHERE ? < stream_id AND stream_id <= ?"
+                " ORDER BY stream_id ASC LIMIT ?"
+            )
+            txn.execute(sql, (last_id, current_id, limit))
+            return txn.fetchall()
+
+        return await self.db_pool.runInteraction(
+            "get_updated_room_account_data", get_updated_room_account_data_txn
+        )
+
+    def get_updated_account_data_for_user(self, user_id, stream_id):
+        """Get all the client account_data for a that's changed for a user
+
+        Args:
+            user_id(str): The user to get the account_data for.
+            stream_id(int): The point in the stream since which to get updates
+        Returns:
+            A deferred pair of a dict of global account_data and a dict
+            mapping from room_id string to per room account_data dicts.
+        """
+
+        def get_updated_account_data_for_user_txn(txn):
+            sql = (
+                "SELECT account_data_type, content FROM account_data"
+                " WHERE user_id = ? AND stream_id > ?"
+            )
+
+            txn.execute(sql, (user_id, stream_id))
+
+            global_account_data = {row[0]: db_to_json(row[1]) for row in txn}
+
+            sql = (
+                "SELECT room_id, account_data_type, content FROM room_account_data"
+                " WHERE user_id = ? AND stream_id > ?"
+            )
+
+            txn.execute(sql, (user_id, stream_id))
+
+            account_data_by_room = {}
+            for row in txn:
+                room_account_data = account_data_by_room.setdefault(row[0], {})
+                room_account_data[row[1]] = db_to_json(row[2])
+
+            return global_account_data, account_data_by_room
+
+        changed = self._account_data_stream_cache.has_entity_changed(
+            user_id, int(stream_id)
+        )
+        if not changed:
+            return defer.succeed(({}, {}))
+
+        return self.db_pool.runInteraction(
+            "get_updated_account_data_for_user", get_updated_account_data_for_user_txn
+        )
+
+    @cachedInlineCallbacks(num_args=2, cache_context=True, max_entries=5000)
+    def is_ignored_by(self, ignored_user_id, ignorer_user_id, cache_context):
+        ignored_account_data = yield self.get_global_account_data_by_type_for_user(
+            "m.ignored_user_list",
+            ignorer_user_id,
+            on_invalidate=cache_context.invalidate,
+        )
+        if not ignored_account_data:
+            return False
+
+        return ignored_user_id in ignored_account_data.get("ignored_users", {})
+
+
+class AccountDataStore(AccountDataWorkerStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        self._account_data_id_gen = StreamIdGenerator(
+            db_conn,
+            "account_data_max_stream_id",
+            "stream_id",
+            extra_tables=[
+                ("room_account_data", "stream_id"),
+                ("room_tags_revisions", "stream_id"),
+            ],
+        )
+
+        super(AccountDataStore, self).__init__(database, db_conn, hs)
+
+    def get_max_account_data_stream_id(self):
+        """Get the current max stream id for the private user data stream
+
+        Returns:
+            A deferred int.
+        """
+        return self._account_data_id_gen.get_current_token()
+
+    @defer.inlineCallbacks
+    def add_account_data_to_room(self, user_id, room_id, account_data_type, content):
+        """Add some account_data to a room for a user.
+        Args:
+            user_id(str): The user to add a tag for.
+            room_id(str): The room to add a tag for.
+            account_data_type(str): The type of account_data to add.
+            content(dict): A json object to associate with the tag.
+        Returns:
+            A deferred that completes once the account_data has been added.
+        """
+        content_json = json.dumps(content)
+
+        with self._account_data_id_gen.get_next() as next_id:
+            # no need to lock here as room_account_data has a unique constraint
+            # on (user_id, room_id, account_data_type) so simple_upsert will
+            # retry if there is a conflict.
+            yield self.db_pool.simple_upsert(
+                desc="add_room_account_data",
+                table="room_account_data",
+                keyvalues={
+                    "user_id": user_id,
+                    "room_id": room_id,
+                    "account_data_type": account_data_type,
+                },
+                values={"stream_id": next_id, "content": content_json},
+                lock=False,
+            )
+
+            # it's theoretically possible for the above to succeed and the
+            # below to fail - in which case we might reuse a stream id on
+            # restart, and the above update might not get propagated. That
+            # doesn't sound any worse than the whole update getting lost,
+            # which is what would happen if we combined the two into one
+            # transaction.
+            yield self._update_max_stream_id(next_id)
+
+            self._account_data_stream_cache.entity_has_changed(user_id, next_id)
+            self.get_account_data_for_user.invalidate((user_id,))
+            self.get_account_data_for_room.invalidate((user_id, room_id))
+            self.get_account_data_for_room_and_type.prefill(
+                (user_id, room_id, account_data_type), content
+            )
+
+        result = self._account_data_id_gen.get_current_token()
+        return result
+
+    @defer.inlineCallbacks
+    def add_account_data_for_user(self, user_id, account_data_type, content):
+        """Add some account_data to a room for a user.
+        Args:
+            user_id(str): The user to add a tag for.
+            account_data_type(str): The type of account_data to add.
+            content(dict): A json object to associate with the tag.
+        Returns:
+            A deferred that completes once the account_data has been added.
+        """
+        content_json = json.dumps(content)
+
+        with self._account_data_id_gen.get_next() as next_id:
+            # no need to lock here as account_data has a unique constraint on
+            # (user_id, account_data_type) so simple_upsert will retry if
+            # there is a conflict.
+            yield self.db_pool.simple_upsert(
+                desc="add_user_account_data",
+                table="account_data",
+                keyvalues={"user_id": user_id, "account_data_type": account_data_type},
+                values={"stream_id": next_id, "content": content_json},
+                lock=False,
+            )
+
+            # it's theoretically possible for the above to succeed and the
+            # below to fail - in which case we might reuse a stream id on
+            # restart, and the above update might not get propagated. That
+            # doesn't sound any worse than the whole update getting lost,
+            # which is what would happen if we combined the two into one
+            # transaction.
+            #
+            # Note: This is only here for backwards compat to allow admins to
+            # roll back to a previous Synapse version. Next time we update the
+            # database version we can remove this table.
+            yield self._update_max_stream_id(next_id)
+
+            self._account_data_stream_cache.entity_has_changed(user_id, next_id)
+            self.get_account_data_for_user.invalidate((user_id,))
+            self.get_global_account_data_by_type_for_user.invalidate(
+                (account_data_type, user_id)
+            )
+
+        result = self._account_data_id_gen.get_current_token()
+        return result
+
+    def _update_max_stream_id(self, next_id):
+        """Update the max stream_id
+
+        Args:
+            next_id(int): The the revision to advance to.
+        """
+
+        # Note: This is only here for backwards compat to allow admins to
+        # roll back to a previous Synapse version. Next time we update the
+        # database version we can remove this table.
+
+        def _update(txn):
+            update_max_id_sql = (
+                "UPDATE account_data_max_stream_id"
+                " SET stream_id = ?"
+                " WHERE stream_id < ?"
+            )
+            txn.execute(update_max_id_sql, (next_id, next_id))
+
+        return self.db_pool.runInteraction("update_account_data_max_stream_id", _update)
diff --git a/synapse/storage/databases/main/appservice.py b/synapse/storage/databases/main/appservice.py
new file mode 100644
index 0000000000..055a3962dc
--- /dev/null
+++ b/synapse/storage/databases/main/appservice.py
@@ -0,0 +1,374 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015, 2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+import re
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.appservice import AppServiceTransaction
+from synapse.config.appservice import load_appservices
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.events_worker import EventsWorkerStore
+
+logger = logging.getLogger(__name__)
+
+
+def _make_exclusive_regex(services_cache):
+    # We precompile a regex constructed from all the regexes that the AS's
+    # have registered for exclusive users.
+    exclusive_user_regexes = [
+        regex.pattern
+        for service in services_cache
+        for regex in service.get_exclusive_user_regexes()
+    ]
+    if exclusive_user_regexes:
+        exclusive_user_regex = "|".join("(" + r + ")" for r in exclusive_user_regexes)
+        exclusive_user_regex = re.compile(exclusive_user_regex)
+    else:
+        # We handle this case specially otherwise the constructed regex
+        # will always match
+        exclusive_user_regex = None
+
+    return exclusive_user_regex
+
+
+class ApplicationServiceWorkerStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        self.services_cache = load_appservices(
+            hs.hostname, hs.config.app_service_config_files
+        )
+        self.exclusive_user_regex = _make_exclusive_regex(self.services_cache)
+
+        super(ApplicationServiceWorkerStore, self).__init__(database, db_conn, hs)
+
+    def get_app_services(self):
+        return self.services_cache
+
+    def get_if_app_services_interested_in_user(self, user_id):
+        """Check if the user is one associated with an app service (exclusively)
+        """
+        if self.exclusive_user_regex:
+            return bool(self.exclusive_user_regex.match(user_id))
+        else:
+            return False
+
+    def get_app_service_by_user_id(self, user_id):
+        """Retrieve an application service from their user ID.
+
+        All application services have associated with them a particular user ID.
+        There is no distinguishing feature on the user ID which indicates it
+        represents an application service. This function allows you to map from
+        a user ID to an application service.
+
+        Args:
+            user_id(str): The user ID to see if it is an application service.
+        Returns:
+            synapse.appservice.ApplicationService or None.
+        """
+        for service in self.services_cache:
+            if service.sender == user_id:
+                return service
+        return None
+
+    def get_app_service_by_token(self, token):
+        """Get the application service with the given appservice token.
+
+        Args:
+            token (str): The application service token.
+        Returns:
+            synapse.appservice.ApplicationService or None.
+        """
+        for service in self.services_cache:
+            if service.token == token:
+                return service
+        return None
+
+    def get_app_service_by_id(self, as_id):
+        """Get the application service with the given appservice ID.
+
+        Args:
+            as_id (str): The application service ID.
+        Returns:
+            synapse.appservice.ApplicationService or None.
+        """
+        for service in self.services_cache:
+            if service.id == as_id:
+                return service
+        return None
+
+
+class ApplicationServiceStore(ApplicationServiceWorkerStore):
+    # This is currently empty due to there not being any AS storage functions
+    # that can't be run on the workers. Since this may change in future, and
+    # to keep consistency with the other stores, we keep this empty class for
+    # now.
+    pass
+
+
+class ApplicationServiceTransactionWorkerStore(
+    ApplicationServiceWorkerStore, EventsWorkerStore
+):
+    @defer.inlineCallbacks
+    def get_appservices_by_state(self, state):
+        """Get a list of application services based on their state.
+
+        Args:
+            state(ApplicationServiceState): The state to filter on.
+        Returns:
+            A Deferred which resolves to a list of ApplicationServices, which
+            may be empty.
+        """
+        results = yield self.db_pool.simple_select_list(
+            "application_services_state", {"state": state}, ["as_id"]
+        )
+        # NB: This assumes this class is linked with ApplicationServiceStore
+        as_list = self.get_app_services()
+        services = []
+
+        for res in results:
+            for service in as_list:
+                if service.id == res["as_id"]:
+                    services.append(service)
+        return services
+
+    @defer.inlineCallbacks
+    def get_appservice_state(self, service):
+        """Get the application service state.
+
+        Args:
+            service(ApplicationService): The service whose state to set.
+        Returns:
+            A Deferred which resolves to ApplicationServiceState.
+        """
+        result = yield self.db_pool.simple_select_one(
+            "application_services_state",
+            {"as_id": service.id},
+            ["state"],
+            allow_none=True,
+            desc="get_appservice_state",
+        )
+        if result:
+            return result.get("state")
+        return None
+
+    def set_appservice_state(self, service, state):
+        """Set the application service state.
+
+        Args:
+            service(ApplicationService): The service whose state to set.
+            state(ApplicationServiceState): The connectivity state to apply.
+        Returns:
+            A Deferred which resolves when the state was set successfully.
+        """
+        return self.db_pool.simple_upsert(
+            "application_services_state", {"as_id": service.id}, {"state": state}
+        )
+
+    def create_appservice_txn(self, service, events):
+        """Atomically creates a new transaction for this application service
+        with the given list of events.
+
+        Args:
+            service(ApplicationService): The service who the transaction is for.
+            events(list<Event>): A list of events to put in the transaction.
+        Returns:
+            AppServiceTransaction: A new transaction.
+        """
+
+        def _create_appservice_txn(txn):
+            # work out new txn id (highest txn id for this service += 1)
+            # The highest id may be the last one sent (in which case it is last_txn)
+            # or it may be the highest in the txns list (which are waiting to be/are
+            # being sent)
+            last_txn_id = self._get_last_txn(txn, service.id)
+
+            txn.execute(
+                "SELECT MAX(txn_id) FROM application_services_txns WHERE as_id=?",
+                (service.id,),
+            )
+            highest_txn_id = txn.fetchone()[0]
+            if highest_txn_id is None:
+                highest_txn_id = 0
+
+            new_txn_id = max(highest_txn_id, last_txn_id) + 1
+
+            # Insert new txn into txn table
+            event_ids = json.dumps([e.event_id for e in events])
+            txn.execute(
+                "INSERT INTO application_services_txns(as_id, txn_id, event_ids) "
+                "VALUES(?,?,?)",
+                (service.id, new_txn_id, event_ids),
+            )
+            return AppServiceTransaction(service=service, id=new_txn_id, events=events)
+
+        return self.db_pool.runInteraction(
+            "create_appservice_txn", _create_appservice_txn
+        )
+
+    def complete_appservice_txn(self, txn_id, service):
+        """Completes an application service transaction.
+
+        Args:
+            txn_id(str): The transaction ID being completed.
+            service(ApplicationService): The application service which was sent
+            this transaction.
+        Returns:
+            A Deferred which resolves if this transaction was stored
+            successfully.
+        """
+        txn_id = int(txn_id)
+
+        def _complete_appservice_txn(txn):
+            # Debugging query: Make sure the txn being completed is EXACTLY +1 from
+            # what was there before. If it isn't, we've got problems (e.g. the AS
+            # has probably missed some events), so whine loudly but still continue,
+            # since it shouldn't fail completion of the transaction.
+            last_txn_id = self._get_last_txn(txn, service.id)
+            if (last_txn_id + 1) != txn_id:
+                logger.error(
+                    "appservice: Completing a transaction which has an ID > 1 from "
+                    "the last ID sent to this AS. We've either dropped events or "
+                    "sent it to the AS out of order. FIX ME. last_txn=%s "
+                    "completing_txn=%s service_id=%s",
+                    last_txn_id,
+                    txn_id,
+                    service.id,
+                )
+
+            # Set current txn_id for AS to 'txn_id'
+            self.db_pool.simple_upsert_txn(
+                txn,
+                "application_services_state",
+                {"as_id": service.id},
+                {"last_txn": txn_id},
+            )
+
+            # Delete txn
+            self.db_pool.simple_delete_txn(
+                txn,
+                "application_services_txns",
+                {"txn_id": txn_id, "as_id": service.id},
+            )
+
+        return self.db_pool.runInteraction(
+            "complete_appservice_txn", _complete_appservice_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_oldest_unsent_txn(self, service):
+        """Get the oldest transaction which has not been sent for this
+        service.
+
+        Args:
+            service(ApplicationService): The app service to get the oldest txn.
+        Returns:
+            A Deferred which resolves to an AppServiceTransaction or
+            None.
+        """
+
+        def _get_oldest_unsent_txn(txn):
+            # Monotonically increasing txn ids, so just select the smallest
+            # one in the txns table (we delete them when they are sent)
+            txn.execute(
+                "SELECT * FROM application_services_txns WHERE as_id=?"
+                " ORDER BY txn_id ASC LIMIT 1",
+                (service.id,),
+            )
+            rows = self.db_pool.cursor_to_dict(txn)
+            if not rows:
+                return None
+
+            entry = rows[0]
+
+            return entry
+
+        entry = yield self.db_pool.runInteraction(
+            "get_oldest_unsent_appservice_txn", _get_oldest_unsent_txn
+        )
+
+        if not entry:
+            return None
+
+        event_ids = db_to_json(entry["event_ids"])
+
+        events = yield self.get_events_as_list(event_ids)
+
+        return AppServiceTransaction(service=service, id=entry["txn_id"], events=events)
+
+    def _get_last_txn(self, txn, service_id):
+        txn.execute(
+            "SELECT last_txn FROM application_services_state WHERE as_id=?",
+            (service_id,),
+        )
+        last_txn_id = txn.fetchone()
+        if last_txn_id is None or last_txn_id[0] is None:  # no row exists
+            return 0
+        else:
+            return int(last_txn_id[0])  # select 'last_txn' col
+
+    def set_appservice_last_pos(self, pos):
+        def set_appservice_last_pos_txn(txn):
+            txn.execute(
+                "UPDATE appservice_stream_position SET stream_ordering = ?", (pos,)
+            )
+
+        return self.db_pool.runInteraction(
+            "set_appservice_last_pos", set_appservice_last_pos_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_new_events_for_appservice(self, current_id, limit):
+        """Get all new evnets"""
+
+        def get_new_events_for_appservice_txn(txn):
+            sql = (
+                "SELECT e.stream_ordering, e.event_id"
+                " FROM events AS e"
+                " WHERE"
+                " (SELECT stream_ordering FROM appservice_stream_position)"
+                "     < e.stream_ordering"
+                " AND e.stream_ordering <= ?"
+                " ORDER BY e.stream_ordering ASC"
+                " LIMIT ?"
+            )
+
+            txn.execute(sql, (current_id, limit))
+            rows = txn.fetchall()
+
+            upper_bound = current_id
+            if len(rows) == limit:
+                upper_bound = rows[-1][0]
+
+            return upper_bound, [row[1] for row in rows]
+
+        upper_bound, event_ids = yield self.db_pool.runInteraction(
+            "get_new_events_for_appservice", get_new_events_for_appservice_txn
+        )
+
+        events = yield self.get_events_as_list(event_ids)
+
+        return upper_bound, events
+
+
+class ApplicationServiceTransactionStore(ApplicationServiceTransactionWorkerStore):
+    # This is currently empty due to there not being any AS storage functions
+    # that can't be run on the workers. Since this may change in future, and
+    # to keep consistency with the other stores, we keep this empty class for
+    # now.
+    pass
diff --git a/synapse/storage/databases/main/cache.py b/synapse/storage/databases/main/cache.py
new file mode 100644
index 0000000000..683afde52b
--- /dev/null
+++ b/synapse/storage/databases/main/cache.py
@@ -0,0 +1,307 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+import itertools
+import logging
+from typing import Any, Iterable, List, Optional, Tuple
+
+from synapse.api.constants import EventTypes
+from synapse.replication.tcp.streams import BackfillStream, CachesStream
+from synapse.replication.tcp.streams.events import (
+    EventsStream,
+    EventsStreamCurrentStateRow,
+    EventsStreamEventRow,
+)
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool
+from synapse.storage.engines import PostgresEngine
+from synapse.util.iterutils import batch_iter
+
+logger = logging.getLogger(__name__)
+
+
+# This is a special cache name we use to batch multiple invalidations of caches
+# based on the current state when notifying workers over replication.
+CURRENT_STATE_CACHE_NAME = "cs_cache_fake"
+
+
+class CacheInvalidationWorkerStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super().__init__(database, db_conn, hs)
+
+        self._instance_name = hs.get_instance_name()
+
+    async def get_all_updated_caches(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for caches replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_updated_caches_txn(txn):
+            # We purposefully don't bound by the current token, as we want to
+            # send across cache invalidations as quickly as possible. Cache
+            # invalidations are idempotent, so duplicates are fine.
+            sql = """
+                SELECT stream_id, cache_func, keys, invalidation_ts
+                FROM cache_invalidation_stream_by_instance
+                WHERE stream_id > ? AND instance_name = ?
+                ORDER BY stream_id ASC
+                LIMIT ?
+            """
+            txn.execute(sql, (last_id, instance_name, limit))
+            updates = [(row[0], row[1:]) for row in txn]
+            limited = False
+            upto_token = current_id
+            if len(updates) >= limit:
+                upto_token = updates[-1][0]
+                limited = True
+
+            return updates, upto_token, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_updated_caches", get_all_updated_caches_txn
+        )
+
+    def process_replication_rows(self, stream_name, instance_name, token, rows):
+        if stream_name == EventsStream.NAME:
+            for row in rows:
+                self._process_event_stream_row(token, row)
+        elif stream_name == BackfillStream.NAME:
+            for row in rows:
+                self._invalidate_caches_for_event(
+                    -token,
+                    row.event_id,
+                    row.room_id,
+                    row.type,
+                    row.state_key,
+                    row.redacts,
+                    row.relates_to,
+                    backfilled=True,
+                )
+        elif stream_name == CachesStream.NAME:
+            if self._cache_id_gen:
+                self._cache_id_gen.advance(instance_name, token)
+
+            for row in rows:
+                if row.cache_func == CURRENT_STATE_CACHE_NAME:
+                    if row.keys is None:
+                        raise Exception(
+                            "Can't send an 'invalidate all' for current state cache"
+                        )
+
+                    room_id = row.keys[0]
+                    members_changed = set(row.keys[1:])
+                    self._invalidate_state_caches(room_id, members_changed)
+                else:
+                    self._attempt_to_invalidate_cache(row.cache_func, row.keys)
+
+        super().process_replication_rows(stream_name, instance_name, token, rows)
+
+    def _process_event_stream_row(self, token, row):
+        data = row.data
+
+        if row.type == EventsStreamEventRow.TypeId:
+            self._invalidate_caches_for_event(
+                token,
+                data.event_id,
+                data.room_id,
+                data.type,
+                data.state_key,
+                data.redacts,
+                data.relates_to,
+                backfilled=False,
+            )
+        elif row.type == EventsStreamCurrentStateRow.TypeId:
+            self._curr_state_delta_stream_cache.entity_has_changed(
+                row.data.room_id, token
+            )
+
+            if data.type == EventTypes.Member:
+                self.get_rooms_for_user_with_stream_ordering.invalidate(
+                    (data.state_key,)
+                )
+        else:
+            raise Exception("Unknown events stream row type %s" % (row.type,))
+
+    def _invalidate_caches_for_event(
+        self,
+        stream_ordering,
+        event_id,
+        room_id,
+        etype,
+        state_key,
+        redacts,
+        relates_to,
+        backfilled,
+    ):
+        self._invalidate_get_event_cache(event_id)
+
+        self.get_latest_event_ids_in_room.invalidate((room_id,))
+
+        self.get_unread_message_count_for_user.invalidate_many((room_id,))
+        self.get_unread_event_push_actions_by_room_for_user.invalidate_many((room_id,))
+
+        if not backfilled:
+            self._events_stream_cache.entity_has_changed(room_id, stream_ordering)
+
+        if redacts:
+            self._invalidate_get_event_cache(redacts)
+
+        if etype == EventTypes.Member:
+            self._membership_stream_cache.entity_has_changed(state_key, stream_ordering)
+            self.get_invited_rooms_for_local_user.invalidate((state_key,))
+
+        if relates_to:
+            self.get_relations_for_event.invalidate_many((relates_to,))
+            self.get_aggregation_groups_for_event.invalidate_many((relates_to,))
+            self.get_applicable_edit.invalidate((relates_to,))
+
+    async def invalidate_cache_and_stream(self, cache_name: str, keys: Tuple[Any, ...]):
+        """Invalidates the cache and adds it to the cache stream so slaves
+        will know to invalidate their caches.
+
+        This should only be used to invalidate caches where slaves won't
+        otherwise know from other replication streams that the cache should
+        be invalidated.
+        """
+        cache_func = getattr(self, cache_name, None)
+        if not cache_func:
+            return
+
+        cache_func.invalidate(keys)
+        await self.db_pool.runInteraction(
+            "invalidate_cache_and_stream",
+            self._send_invalidation_to_replication,
+            cache_func.__name__,
+            keys,
+        )
+
+    def _invalidate_cache_and_stream(self, txn, cache_func, keys):
+        """Invalidates the cache and adds it to the cache stream so slaves
+        will know to invalidate their caches.
+
+        This should only be used to invalidate caches where slaves won't
+        otherwise know from other replication streams that the cache should
+        be invalidated.
+        """
+        txn.call_after(cache_func.invalidate, keys)
+        self._send_invalidation_to_replication(txn, cache_func.__name__, keys)
+
+    def _invalidate_all_cache_and_stream(self, txn, cache_func):
+        """Invalidates the entire cache and adds it to the cache stream so slaves
+        will know to invalidate their caches.
+        """
+
+        txn.call_after(cache_func.invalidate_all)
+        self._send_invalidation_to_replication(txn, cache_func.__name__, None)
+
+    def _invalidate_state_caches_and_stream(self, txn, room_id, members_changed):
+        """Special case invalidation of caches based on current state.
+
+        We special case this so that we can batch the cache invalidations into a
+        single replication poke.
+
+        Args:
+            txn
+            room_id (str): Room where state changed
+            members_changed (iterable[str]): The user_ids of members that have changed
+        """
+        txn.call_after(self._invalidate_state_caches, room_id, members_changed)
+
+        if members_changed:
+            # We need to be careful that the size of the `members_changed` list
+            # isn't so large that it causes problems sending over replication, so we
+            # send them in chunks.
+            # Max line length is 16K, and max user ID length is 255, so 50 should
+            # be safe.
+            for chunk in batch_iter(members_changed, 50):
+                keys = itertools.chain([room_id], chunk)
+                self._send_invalidation_to_replication(
+                    txn, CURRENT_STATE_CACHE_NAME, keys
+                )
+        else:
+            # if no members changed, we still need to invalidate the other caches.
+            self._send_invalidation_to_replication(
+                txn, CURRENT_STATE_CACHE_NAME, [room_id]
+            )
+
+    def _send_invalidation_to_replication(
+        self, txn, cache_name: str, keys: Optional[Iterable[Any]]
+    ):
+        """Notifies replication that given cache has been invalidated.
+
+        Note that this does *not* invalidate the cache locally.
+
+        Args:
+            txn
+            cache_name
+            keys: Entry to invalidate. If None will invalidate all.
+        """
+
+        if cache_name == CURRENT_STATE_CACHE_NAME and keys is None:
+            raise Exception(
+                "Can't stream invalidate all with magic current state cache"
+            )
+
+        if isinstance(self.database_engine, PostgresEngine):
+            # get_next() returns a context manager which is designed to wrap
+            # the transaction. However, we want to only get an ID when we want
+            # to use it, here, so we need to call __enter__ manually, and have
+            # __exit__ called after the transaction finishes.
+            stream_id = self._cache_id_gen.get_next_txn(txn)
+            txn.call_after(self.hs.get_notifier().on_new_replication_data)
+
+            if keys is not None:
+                keys = list(keys)
+
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="cache_invalidation_stream_by_instance",
+                values={
+                    "stream_id": stream_id,
+                    "instance_name": self._instance_name,
+                    "cache_func": cache_name,
+                    "keys": keys,
+                    "invalidation_ts": self.clock.time_msec(),
+                },
+            )
+
+    def get_cache_stream_token(self, instance_name):
+        if self._cache_id_gen:
+            return self._cache_id_gen.get_current_token(instance_name)
+        else:
+            return 0
diff --git a/synapse/storage/databases/main/censor_events.py b/synapse/storage/databases/main/censor_events.py
new file mode 100644
index 0000000000..1de8249563
--- /dev/null
+++ b/synapse/storage/databases/main/censor_events.py
@@ -0,0 +1,210 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from typing import TYPE_CHECKING
+
+from twisted.internet import defer
+
+from synapse.events.utils import prune_event_dict
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.cache import CacheInvalidationWorkerStore
+from synapse.storage.databases.main.events import encode_json
+from synapse.storage.databases.main.events_worker import EventsWorkerStore
+
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
+
+logger = logging.getLogger(__name__)
+
+
+class CensorEventsStore(EventsWorkerStore, CacheInvalidationWorkerStore, SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs: "HomeServer"):
+        super().__init__(database, db_conn, hs)
+
+        def _censor_redactions():
+            return run_as_background_process(
+                "_censor_redactions", self._censor_redactions
+            )
+
+        if self.hs.config.redaction_retention_period is not None:
+            hs.get_clock().looping_call(_censor_redactions, 5 * 60 * 1000)
+
+    async def _censor_redactions(self):
+        """Censors all redactions older than the configured period that haven't
+        been censored yet.
+
+        By censor we mean update the event_json table with the redacted event.
+        """
+
+        if self.hs.config.redaction_retention_period is None:
+            return
+
+        if not (
+            await self.db_pool.updates.has_completed_background_update(
+                "redactions_have_censored_ts_idx"
+            )
+        ):
+            # We don't want to run this until the appropriate index has been
+            # created.
+            return
+
+        before_ts = self._clock.time_msec() - self.hs.config.redaction_retention_period
+
+        # We fetch all redactions that:
+        #   1. point to an event we have,
+        #   2. has a received_ts from before the cut off, and
+        #   3. we haven't yet censored.
+        #
+        # This is limited to 100 events to ensure that we don't try and do too
+        # much at once. We'll get called again so this should eventually catch
+        # up.
+        sql = """
+            SELECT redactions.event_id, redacts FROM redactions
+            LEFT JOIN events AS original_event ON (
+                redacts = original_event.event_id
+            )
+            WHERE NOT have_censored
+            AND redactions.received_ts <= ?
+            ORDER BY redactions.received_ts ASC
+            LIMIT ?
+        """
+
+        rows = await self.db_pool.execute(
+            "_censor_redactions_fetch", None, sql, before_ts, 100
+        )
+
+        updates = []
+
+        for redaction_id, event_id in rows:
+            redaction_event = await self.get_event(redaction_id, allow_none=True)
+            original_event = await self.get_event(
+                event_id, allow_rejected=True, allow_none=True
+            )
+
+            # The SQL above ensures that we have both the redaction and
+            # original event, so if the `get_event` calls return None it
+            # means that the redaction wasn't allowed. Either way we know that
+            # the result won't change so we mark the fact that we've checked.
+            if (
+                redaction_event
+                and original_event
+                and original_event.internal_metadata.is_redacted()
+            ):
+                # Redaction was allowed
+                pruned_json = encode_json(
+                    prune_event_dict(
+                        original_event.room_version, original_event.get_dict()
+                    )
+                )
+            else:
+                # Redaction wasn't allowed
+                pruned_json = None
+
+            updates.append((redaction_id, event_id, pruned_json))
+
+        def _update_censor_txn(txn):
+            for redaction_id, event_id, pruned_json in updates:
+                if pruned_json:
+                    self._censor_event_txn(txn, event_id, pruned_json)
+
+                self.db_pool.simple_update_one_txn(
+                    txn,
+                    table="redactions",
+                    keyvalues={"event_id": redaction_id},
+                    updatevalues={"have_censored": True},
+                )
+
+        await self.db_pool.runInteraction("_update_censor_txn", _update_censor_txn)
+
+    def _censor_event_txn(self, txn, event_id, pruned_json):
+        """Censor an event by replacing its JSON in the event_json table with the
+        provided pruned JSON.
+
+        Args:
+            txn (LoggingTransaction): The database transaction.
+            event_id (str): The ID of the event to censor.
+            pruned_json (str): The pruned JSON
+        """
+        self.db_pool.simple_update_one_txn(
+            txn,
+            table="event_json",
+            keyvalues={"event_id": event_id},
+            updatevalues={"json": pruned_json},
+        )
+
+    @defer.inlineCallbacks
+    def expire_event(self, event_id):
+        """Retrieve and expire an event that has expired, and delete its associated
+        expiry timestamp. If the event can't be retrieved, delete its associated
+        timestamp so we don't try to expire it again in the future.
+
+        Args:
+             event_id (str): The ID of the event to delete.
+        """
+        # Try to retrieve the event's content from the database or the event cache.
+        event = yield self.get_event(event_id)
+
+        def delete_expired_event_txn(txn):
+            # Delete the expiry timestamp associated with this event from the database.
+            self._delete_event_expiry_txn(txn, event_id)
+
+            if not event:
+                # If we can't find the event, log a warning and delete the expiry date
+                # from the database so that we don't try to expire it again in the
+                # future.
+                logger.warning(
+                    "Can't expire event %s because we don't have it.", event_id
+                )
+                return
+
+            # Prune the event's dict then convert it to JSON.
+            pruned_json = encode_json(
+                prune_event_dict(event.room_version, event.get_dict())
+            )
+
+            # Update the event_json table to replace the event's JSON with the pruned
+            # JSON.
+            self._censor_event_txn(txn, event.event_id, pruned_json)
+
+            # We need to invalidate the event cache entry for this event because we
+            # changed its content in the database. We can't call
+            # self._invalidate_cache_and_stream because self.get_event_cache isn't of the
+            # right type.
+            txn.call_after(self._get_event_cache.invalidate, (event.event_id,))
+            # Send that invalidation to replication so that other workers also invalidate
+            # the event cache.
+            self._send_invalidation_to_replication(
+                txn, "_get_event_cache", (event.event_id,)
+            )
+
+        yield self.db_pool.runInteraction(
+            "delete_expired_event", delete_expired_event_txn
+        )
+
+    def _delete_event_expiry_txn(self, txn, event_id):
+        """Delete the expiry timestamp associated with an event ID without deleting the
+        actual event.
+
+        Args:
+            txn (LoggingTransaction): The transaction to use to perform the deletion.
+            event_id (str): The event ID to delete the associated expiry timestamp of.
+        """
+        return self.db_pool.simple_delete_txn(
+            txn=txn, table="event_expiry", keyvalues={"event_id": event_id}
+        )
diff --git a/synapse/storage/databases/main/client_ips.py b/synapse/storage/databases/main/client_ips.py
new file mode 100644
index 0000000000..712c8d0264
--- /dev/null
+++ b/synapse/storage/databases/main/client_ips.py
@@ -0,0 +1,580 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from twisted.internet import defer
+
+from synapse.metrics.background_process_metrics import wrap_as_background_process
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool, make_tuple_comparison_clause
+from synapse.util.caches.descriptors import Cache
+
+logger = logging.getLogger(__name__)
+
+# Number of msec of granularity to store the user IP 'last seen' time. Smaller
+# times give more inserts into the database even for readonly API hits
+# 120 seconds == 2 minutes
+LAST_SEEN_GRANULARITY = 120 * 1000
+
+
+class ClientIpBackgroundUpdateStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(ClientIpBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        self.db_pool.updates.register_background_index_update(
+            "user_ips_device_index",
+            index_name="user_ips_device_id",
+            table="user_ips",
+            columns=["user_id", "device_id", "last_seen"],
+        )
+
+        self.db_pool.updates.register_background_index_update(
+            "user_ips_last_seen_index",
+            index_name="user_ips_last_seen",
+            table="user_ips",
+            columns=["user_id", "last_seen"],
+        )
+
+        self.db_pool.updates.register_background_index_update(
+            "user_ips_last_seen_only_index",
+            index_name="user_ips_last_seen_only",
+            table="user_ips",
+            columns=["last_seen"],
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            "user_ips_analyze", self._analyze_user_ip
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            "user_ips_remove_dupes", self._remove_user_ip_dupes
+        )
+
+        # Register a unique index
+        self.db_pool.updates.register_background_index_update(
+            "user_ips_device_unique_index",
+            index_name="user_ips_user_token_ip_unique_index",
+            table="user_ips",
+            columns=["user_id", "access_token", "ip"],
+            unique=True,
+        )
+
+        # Drop the old non-unique index
+        self.db_pool.updates.register_background_update_handler(
+            "user_ips_drop_nonunique_index", self._remove_user_ip_nonunique
+        )
+
+        # Update the last seen info in devices.
+        self.db_pool.updates.register_background_update_handler(
+            "devices_last_seen", self._devices_last_seen_update
+        )
+
+    @defer.inlineCallbacks
+    def _remove_user_ip_nonunique(self, progress, batch_size):
+        def f(conn):
+            txn = conn.cursor()
+            txn.execute("DROP INDEX IF EXISTS user_ips_user_ip")
+            txn.close()
+
+        yield self.db_pool.runWithConnection(f)
+        yield self.db_pool.updates._end_background_update(
+            "user_ips_drop_nonunique_index"
+        )
+        return 1
+
+    @defer.inlineCallbacks
+    def _analyze_user_ip(self, progress, batch_size):
+        # Background update to analyze user_ips table before we run the
+        # deduplication background update. The table may not have been analyzed
+        # for ages due to the table locks.
+        #
+        # This will lock out the naive upserts to user_ips while it happens, but
+        # the analyze should be quick (28GB table takes ~10s)
+        def user_ips_analyze(txn):
+            txn.execute("ANALYZE user_ips")
+
+        yield self.db_pool.runInteraction("user_ips_analyze", user_ips_analyze)
+
+        yield self.db_pool.updates._end_background_update("user_ips_analyze")
+
+        return 1
+
+    @defer.inlineCallbacks
+    def _remove_user_ip_dupes(self, progress, batch_size):
+        # This works function works by scanning the user_ips table in batches
+        # based on `last_seen`. For each row in a batch it searches the rest of
+        # the table to see if there are any duplicates, if there are then they
+        # are removed and replaced with a suitable row.
+
+        # Fetch the start of the batch
+        begin_last_seen = progress.get("last_seen", 0)
+
+        def get_last_seen(txn):
+            txn.execute(
+                """
+                SELECT last_seen FROM user_ips
+                WHERE last_seen > ?
+                ORDER BY last_seen
+                LIMIT 1
+                OFFSET ?
+                """,
+                (begin_last_seen, batch_size),
+            )
+            row = txn.fetchone()
+            if row:
+                return row[0]
+            else:
+                return None
+
+        # Get a last seen that has roughly `batch_size` since `begin_last_seen`
+        end_last_seen = yield self.db_pool.runInteraction(
+            "user_ips_dups_get_last_seen", get_last_seen
+        )
+
+        # If it returns None, then we're processing the last batch
+        last = end_last_seen is None
+
+        logger.info(
+            "Scanning for duplicate 'user_ips' rows in range: %s <= last_seen < %s",
+            begin_last_seen,
+            end_last_seen,
+        )
+
+        def remove(txn):
+            # This works by looking at all entries in the given time span, and
+            # then for each (user_id, access_token, ip) tuple in that range
+            # checking for any duplicates in the rest of the table (via a join).
+            # It then only returns entries which have duplicates, and the max
+            # last_seen across all duplicates, which can the be used to delete
+            # all other duplicates.
+            # It is efficient due to the existence of (user_id, access_token,
+            # ip) and (last_seen) indices.
+
+            # Define the search space, which requires handling the last batch in
+            # a different way
+            if last:
+                clause = "? <= last_seen"
+                args = (begin_last_seen,)
+            else:
+                clause = "? <= last_seen AND last_seen < ?"
+                args = (begin_last_seen, end_last_seen)
+
+            # (Note: The DISTINCT in the inner query is important to ensure that
+            # the COUNT(*) is accurate, otherwise double counting may happen due
+            # to the join effectively being a cross product)
+            txn.execute(
+                """
+                SELECT user_id, access_token, ip,
+                       MAX(device_id), MAX(user_agent), MAX(last_seen),
+                       COUNT(*)
+                FROM (
+                    SELECT DISTINCT user_id, access_token, ip
+                    FROM user_ips
+                    WHERE {}
+                ) c
+                INNER JOIN user_ips USING (user_id, access_token, ip)
+                GROUP BY user_id, access_token, ip
+                HAVING count(*) > 1
+                """.format(
+                    clause
+                ),
+                args,
+            )
+            res = txn.fetchall()
+
+            # We've got some duplicates
+            for i in res:
+                user_id, access_token, ip, device_id, user_agent, last_seen, count = i
+
+                # We want to delete the duplicates so we end up with only a
+                # single row.
+                #
+                # The naive way of doing this would be just to delete all rows
+                # and reinsert a constructed row. However, if there are a lot of
+                # duplicate rows this can cause the table to grow a lot, which
+                # can be problematic in two ways:
+                #   1. If user_ips is already large then this can cause the
+                #      table to rapidly grow, potentially filling the disk.
+                #   2. Reinserting a lot of rows can confuse the table
+                #      statistics for postgres, causing it to not use the
+                #      correct indices for the query above, resulting in a full
+                #      table scan. This is incredibly slow for large tables and
+                #      can kill database performance. (This seems to mainly
+                #      happen for the last query where the clause is simply `? <
+                #      last_seen`)
+                #
+                # So instead we want to delete all but *one* of the duplicate
+                # rows. That is hard to do reliably, so we cheat and do a two
+                # step process:
+                #   1. Delete all rows with a last_seen strictly less than the
+                #      max last_seen. This hopefully results in deleting all but
+                #      one row the majority of the time, but there may be
+                #      duplicate last_seen
+                #   2. If multiple rows remain, we fall back to the naive method
+                #      and simply delete all rows and reinsert.
+                #
+                # Note that this relies on no new duplicate rows being inserted,
+                # but if that is happening then this entire process is futile
+                # anyway.
+
+                # Do step 1:
+
+                txn.execute(
+                    """
+                    DELETE FROM user_ips
+                    WHERE user_id = ? AND access_token = ? AND ip = ? AND last_seen < ?
+                    """,
+                    (user_id, access_token, ip, last_seen),
+                )
+                if txn.rowcount == count - 1:
+                    # We deleted all but one of the duplicate rows, i.e. there
+                    # is exactly one remaining and so there is nothing left to
+                    # do.
+                    continue
+                elif txn.rowcount >= count:
+                    raise Exception(
+                        "We deleted more duplicate rows from 'user_ips' than expected"
+                    )
+
+                # The previous step didn't delete enough rows, so we fallback to
+                # step 2:
+
+                # Drop all the duplicates
+                txn.execute(
+                    """
+                    DELETE FROM user_ips
+                    WHERE user_id = ? AND access_token = ? AND ip = ?
+                    """,
+                    (user_id, access_token, ip),
+                )
+
+                # Add in one to be the last_seen
+                txn.execute(
+                    """
+                    INSERT INTO user_ips
+                    (user_id, access_token, ip, device_id, user_agent, last_seen)
+                    VALUES (?, ?, ?, ?, ?, ?)
+                    """,
+                    (user_id, access_token, ip, device_id, user_agent, last_seen),
+                )
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, "user_ips_remove_dupes", {"last_seen": end_last_seen}
+            )
+
+        yield self.db_pool.runInteraction("user_ips_dups_remove", remove)
+
+        if last:
+            yield self.db_pool.updates._end_background_update("user_ips_remove_dupes")
+
+        return batch_size
+
+    @defer.inlineCallbacks
+    def _devices_last_seen_update(self, progress, batch_size):
+        """Background update to insert last seen info into devices table
+        """
+
+        last_user_id = progress.get("last_user_id", "")
+        last_device_id = progress.get("last_device_id", "")
+
+        def _devices_last_seen_update_txn(txn):
+            # This consists of two queries:
+            #
+            #   1. The sub-query searches for the next N devices and joins
+            #      against user_ips to find the max last_seen associated with
+            #      that device.
+            #   2. The outer query then joins again against user_ips on
+            #      user/device/last_seen. This *should* hopefully only
+            #      return one row, but if it does return more than one then
+            #      we'll just end up updating the same device row multiple
+            #      times, which is fine.
+
+            where_clause, where_args = make_tuple_comparison_clause(
+                self.database_engine,
+                [("user_id", last_user_id), ("device_id", last_device_id)],
+            )
+
+            sql = """
+                SELECT
+                    last_seen, ip, user_agent, user_id, device_id
+                FROM (
+                    SELECT
+                        user_id, device_id, MAX(u.last_seen) AS last_seen
+                    FROM devices
+                    INNER JOIN user_ips AS u USING (user_id, device_id)
+                    WHERE %(where_clause)s
+                    GROUP BY user_id, device_id
+                    ORDER BY user_id ASC, device_id ASC
+                    LIMIT ?
+                ) c
+                INNER JOIN user_ips AS u USING (user_id, device_id, last_seen)
+            """ % {
+                "where_clause": where_clause
+            }
+            txn.execute(sql, where_args + [batch_size])
+
+            rows = txn.fetchall()
+            if not rows:
+                return 0
+
+            sql = """
+                UPDATE devices
+                SET last_seen = ?, ip = ?, user_agent = ?
+                WHERE user_id = ? AND device_id = ?
+            """
+            txn.execute_batch(sql, rows)
+
+            _, _, _, user_id, device_id = rows[-1]
+            self.db_pool.updates._background_update_progress_txn(
+                txn,
+                "devices_last_seen",
+                {"last_user_id": user_id, "last_device_id": device_id},
+            )
+
+            return len(rows)
+
+        updated = yield self.db_pool.runInteraction(
+            "_devices_last_seen_update", _devices_last_seen_update_txn
+        )
+
+        if not updated:
+            yield self.db_pool.updates._end_background_update("devices_last_seen")
+
+        return updated
+
+
+class ClientIpStore(ClientIpBackgroundUpdateStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+
+        self.client_ip_last_seen = Cache(
+            name="client_ip_last_seen", keylen=4, max_entries=50000
+        )
+
+        super(ClientIpStore, self).__init__(database, db_conn, hs)
+
+        self.user_ips_max_age = hs.config.user_ips_max_age
+
+        # (user_id, access_token, ip,) -> (user_agent, device_id, last_seen)
+        self._batch_row_update = {}
+
+        self._client_ip_looper = self._clock.looping_call(
+            self._update_client_ips_batch, 5 * 1000
+        )
+        self.hs.get_reactor().addSystemEventTrigger(
+            "before", "shutdown", self._update_client_ips_batch
+        )
+
+        if self.user_ips_max_age:
+            self._clock.looping_call(self._prune_old_user_ips, 5 * 1000)
+
+    @defer.inlineCallbacks
+    def insert_client_ip(
+        self, user_id, access_token, ip, user_agent, device_id, now=None
+    ):
+        if not now:
+            now = int(self._clock.time_msec())
+        key = (user_id, access_token, ip)
+
+        try:
+            last_seen = self.client_ip_last_seen.get(key)
+        except KeyError:
+            last_seen = None
+        yield self.populate_monthly_active_users(user_id)
+        # Rate-limited inserts
+        if last_seen is not None and (now - last_seen) < LAST_SEEN_GRANULARITY:
+            return
+
+        self.client_ip_last_seen.prefill(key, now)
+
+        self._batch_row_update[key] = (user_agent, device_id, now)
+
+    @wrap_as_background_process("update_client_ips")
+    def _update_client_ips_batch(self):
+
+        # If the DB pool has already terminated, don't try updating
+        if not self.db_pool.is_running():
+            return
+
+        to_update = self._batch_row_update
+        self._batch_row_update = {}
+
+        return self.db_pool.runInteraction(
+            "_update_client_ips_batch", self._update_client_ips_batch_txn, to_update
+        )
+
+    def _update_client_ips_batch_txn(self, txn, to_update):
+        if "user_ips" in self.db_pool._unsafe_to_upsert_tables or (
+            not self.database_engine.can_native_upsert
+        ):
+            self.database_engine.lock_table(txn, "user_ips")
+
+        for entry in to_update.items():
+            (user_id, access_token, ip), (user_agent, device_id, last_seen) = entry
+
+            try:
+                self.db_pool.simple_upsert_txn(
+                    txn,
+                    table="user_ips",
+                    keyvalues={
+                        "user_id": user_id,
+                        "access_token": access_token,
+                        "ip": ip,
+                    },
+                    values={
+                        "user_agent": user_agent,
+                        "device_id": device_id,
+                        "last_seen": last_seen,
+                    },
+                    lock=False,
+                )
+
+                # Technically an access token might not be associated with
+                # a device so we need to check.
+                if device_id:
+                    # this is always an update rather than an upsert: the row should
+                    # already exist, and if it doesn't, that may be because it has been
+                    # deleted, and we don't want to re-create it.
+                    self.db_pool.simple_update_txn(
+                        txn,
+                        table="devices",
+                        keyvalues={"user_id": user_id, "device_id": device_id},
+                        updatevalues={
+                            "user_agent": user_agent,
+                            "last_seen": last_seen,
+                            "ip": ip,
+                        },
+                    )
+            except Exception as e:
+                # Failed to upsert, log and continue
+                logger.error("Failed to insert client IP %r: %r", entry, e)
+
+    @defer.inlineCallbacks
+    def get_last_client_ip_by_device(self, user_id, device_id):
+        """For each device_id listed, give the user_ip it was last seen on
+
+        Args:
+            user_id (str)
+            device_id (str): If None fetches all devices for the user
+
+        Returns:
+            defer.Deferred: resolves to a dict, where the keys
+            are (user_id, device_id) tuples. The values are also dicts, with
+            keys giving the column names
+        """
+
+        keyvalues = {"user_id": user_id}
+        if device_id is not None:
+            keyvalues["device_id"] = device_id
+
+        res = yield self.db_pool.simple_select_list(
+            table="devices",
+            keyvalues=keyvalues,
+            retcols=("user_id", "ip", "user_agent", "device_id", "last_seen"),
+        )
+
+        ret = {(d["user_id"], d["device_id"]): d for d in res}
+        for key in self._batch_row_update:
+            uid, access_token, ip = key
+            if uid == user_id:
+                user_agent, did, last_seen = self._batch_row_update[key]
+                if not device_id or did == device_id:
+                    ret[(user_id, device_id)] = {
+                        "user_id": user_id,
+                        "access_token": access_token,
+                        "ip": ip,
+                        "user_agent": user_agent,
+                        "device_id": did,
+                        "last_seen": last_seen,
+                    }
+        return ret
+
+    @defer.inlineCallbacks
+    def get_user_ip_and_agents(self, user):
+        user_id = user.to_string()
+        results = {}
+
+        for key in self._batch_row_update:
+            uid, access_token, ip, = key
+            if uid == user_id:
+                user_agent, _, last_seen = self._batch_row_update[key]
+                results[(access_token, ip)] = (user_agent, last_seen)
+
+        rows = yield self.db_pool.simple_select_list(
+            table="user_ips",
+            keyvalues={"user_id": user_id},
+            retcols=["access_token", "ip", "user_agent", "last_seen"],
+            desc="get_user_ip_and_agents",
+        )
+
+        results.update(
+            ((row["access_token"], row["ip"]), (row["user_agent"], row["last_seen"]))
+            for row in rows
+        )
+        return [
+            {
+                "access_token": access_token,
+                "ip": ip,
+                "user_agent": user_agent,
+                "last_seen": last_seen,
+            }
+            for (access_token, ip), (user_agent, last_seen) in results.items()
+        ]
+
+    @wrap_as_background_process("prune_old_user_ips")
+    async def _prune_old_user_ips(self):
+        """Removes entries in user IPs older than the configured period.
+        """
+
+        if self.user_ips_max_age is None:
+            # Nothing to do
+            return
+
+        if not await self.db_pool.updates.has_completed_background_update(
+            "devices_last_seen"
+        ):
+            # Only start pruning if we have finished populating the devices
+            # last seen info.
+            return
+
+        # We do a slightly funky SQL delete to ensure we don't try and delete
+        # too much at once (as the table may be very large from before we
+        # started pruning).
+        #
+        # This works by finding the max last_seen that is less than the given
+        # time, but has no more than N rows before it, deleting all rows with
+        # a lesser last_seen time. (We COALESCE so that the sub-SELECT always
+        # returns exactly one row).
+        sql = """
+            DELETE FROM user_ips
+            WHERE last_seen <= (
+                SELECT COALESCE(MAX(last_seen), -1)
+                FROM (
+                    SELECT last_seen FROM user_ips
+                    WHERE last_seen <= ?
+                    ORDER BY last_seen ASC
+                    LIMIT 5000
+                ) AS u
+            )
+        """
+
+        timestamp = self.clock.time_msec() - self.user_ips_max_age
+
+        def _prune_old_user_ips_txn(txn):
+            txn.execute(sql, (timestamp,))
+
+        await self.db_pool.runInteraction(
+            "_prune_old_user_ips", _prune_old_user_ips_txn
+        )
diff --git a/synapse/storage/databases/main/deviceinbox.py b/synapse/storage/databases/main/deviceinbox.py
new file mode 100644
index 0000000000..874ecdf8d2
--- /dev/null
+++ b/synapse/storage/databases/main/deviceinbox.py
@@ -0,0 +1,476 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from typing import List, Tuple
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.logging.opentracing import log_kv, set_tag, trace
+from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
+from synapse.storage.database import DatabasePool
+from synapse.util.caches.expiringcache import ExpiringCache
+
+logger = logging.getLogger(__name__)
+
+
+class DeviceInboxWorkerStore(SQLBaseStore):
+    def get_to_device_stream_token(self):
+        return self._device_inbox_id_gen.get_current_token()
+
+    def get_new_messages_for_device(
+        self, user_id, device_id, last_stream_id, current_stream_id, limit=100
+    ):
+        """
+        Args:
+            user_id(str): The recipient user_id.
+            device_id(str): The recipient device_id.
+            current_stream_id(int): The current position of the to device
+                message stream.
+        Returns:
+            Deferred ([dict], int): List of messages for the device and where
+                in the stream the messages got to.
+        """
+        has_changed = self._device_inbox_stream_cache.has_entity_changed(
+            user_id, last_stream_id
+        )
+        if not has_changed:
+            return defer.succeed(([], current_stream_id))
+
+        def get_new_messages_for_device_txn(txn):
+            sql = (
+                "SELECT stream_id, message_json FROM device_inbox"
+                " WHERE user_id = ? AND device_id = ?"
+                " AND ? < stream_id AND stream_id <= ?"
+                " ORDER BY stream_id ASC"
+                " LIMIT ?"
+            )
+            txn.execute(
+                sql, (user_id, device_id, last_stream_id, current_stream_id, limit)
+            )
+            messages = []
+            for row in txn:
+                stream_pos = row[0]
+                messages.append(db_to_json(row[1]))
+            if len(messages) < limit:
+                stream_pos = current_stream_id
+            return messages, stream_pos
+
+        return self.db_pool.runInteraction(
+            "get_new_messages_for_device", get_new_messages_for_device_txn
+        )
+
+    @trace
+    @defer.inlineCallbacks
+    def delete_messages_for_device(self, user_id, device_id, up_to_stream_id):
+        """
+        Args:
+            user_id(str): The recipient user_id.
+            device_id(str): The recipient device_id.
+            up_to_stream_id(int): Where to delete messages up to.
+        Returns:
+            A deferred that resolves to the number of messages deleted.
+        """
+        # If we have cached the last stream id we've deleted up to, we can
+        # check if there is likely to be anything that needs deleting
+        last_deleted_stream_id = self._last_device_delete_cache.get(
+            (user_id, device_id), None
+        )
+
+        set_tag("last_deleted_stream_id", last_deleted_stream_id)
+
+        if last_deleted_stream_id:
+            has_changed = self._device_inbox_stream_cache.has_entity_changed(
+                user_id, last_deleted_stream_id
+            )
+            if not has_changed:
+                log_kv({"message": "No changes in cache since last check"})
+                return 0
+
+        def delete_messages_for_device_txn(txn):
+            sql = (
+                "DELETE FROM device_inbox"
+                " WHERE user_id = ? AND device_id = ?"
+                " AND stream_id <= ?"
+            )
+            txn.execute(sql, (user_id, device_id, up_to_stream_id))
+            return txn.rowcount
+
+        count = yield self.db_pool.runInteraction(
+            "delete_messages_for_device", delete_messages_for_device_txn
+        )
+
+        log_kv(
+            {"message": "deleted {} messages for device".format(count), "count": count}
+        )
+
+        # Update the cache, ensuring that we only ever increase the value
+        last_deleted_stream_id = self._last_device_delete_cache.get(
+            (user_id, device_id), 0
+        )
+        self._last_device_delete_cache[(user_id, device_id)] = max(
+            last_deleted_stream_id, up_to_stream_id
+        )
+
+        return count
+
+    @trace
+    def get_new_device_msgs_for_remote(
+        self, destination, last_stream_id, current_stream_id, limit
+    ):
+        """
+        Args:
+            destination(str): The name of the remote server.
+            last_stream_id(int|long): The last position of the device message stream
+                that the server sent up to.
+            current_stream_id(int|long): The current position of the device
+                message stream.
+        Returns:
+            Deferred ([dict], int|long): List of messages for the device and where
+                in the stream the messages got to.
+        """
+
+        set_tag("destination", destination)
+        set_tag("last_stream_id", last_stream_id)
+        set_tag("current_stream_id", current_stream_id)
+        set_tag("limit", limit)
+
+        has_changed = self._device_federation_outbox_stream_cache.has_entity_changed(
+            destination, last_stream_id
+        )
+        if not has_changed or last_stream_id == current_stream_id:
+            log_kv({"message": "No new messages in stream"})
+            return defer.succeed(([], current_stream_id))
+
+        if limit <= 0:
+            # This can happen if we run out of room for EDUs in the transaction.
+            return defer.succeed(([], last_stream_id))
+
+        @trace
+        def get_new_messages_for_remote_destination_txn(txn):
+            sql = (
+                "SELECT stream_id, messages_json FROM device_federation_outbox"
+                " WHERE destination = ?"
+                " AND ? < stream_id AND stream_id <= ?"
+                " ORDER BY stream_id ASC"
+                " LIMIT ?"
+            )
+            txn.execute(sql, (destination, last_stream_id, current_stream_id, limit))
+            messages = []
+            for row in txn:
+                stream_pos = row[0]
+                messages.append(db_to_json(row[1]))
+            if len(messages) < limit:
+                log_kv({"message": "Set stream position to current position"})
+                stream_pos = current_stream_id
+            return messages, stream_pos
+
+        return self.db_pool.runInteraction(
+            "get_new_device_msgs_for_remote",
+            get_new_messages_for_remote_destination_txn,
+        )
+
+    @trace
+    def delete_device_msgs_for_remote(self, destination, up_to_stream_id):
+        """Used to delete messages when the remote destination acknowledges
+        their receipt.
+
+        Args:
+            destination(str): The destination server_name
+            up_to_stream_id(int): Where to delete messages up to.
+        Returns:
+            A deferred that resolves when the messages have been deleted.
+        """
+
+        def delete_messages_for_remote_destination_txn(txn):
+            sql = (
+                "DELETE FROM device_federation_outbox"
+                " WHERE destination = ?"
+                " AND stream_id <= ?"
+            )
+            txn.execute(sql, (destination, up_to_stream_id))
+
+        return self.db_pool.runInteraction(
+            "delete_device_msgs_for_remote", delete_messages_for_remote_destination_txn
+        )
+
+    async def get_all_new_device_messages(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for to device replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_new_device_messages_txn(txn):
+            # We limit like this as we might have multiple rows per stream_id, and
+            # we want to make sure we always get all entries for any stream_id
+            # we return.
+            upper_pos = min(current_id, last_id + limit)
+            sql = (
+                "SELECT max(stream_id), user_id"
+                " FROM device_inbox"
+                " WHERE ? < stream_id AND stream_id <= ?"
+                " GROUP BY user_id"
+            )
+            txn.execute(sql, (last_id, upper_pos))
+            updates = [(row[0], row[1:]) for row in txn]
+
+            sql = (
+                "SELECT max(stream_id), destination"
+                " FROM device_federation_outbox"
+                " WHERE ? < stream_id AND stream_id <= ?"
+                " GROUP BY destination"
+            )
+            txn.execute(sql, (last_id, upper_pos))
+            updates.extend((row[0], row[1:]) for row in txn)
+
+            # Order by ascending stream ordering
+            updates.sort()
+
+            limited = False
+            upto_token = current_id
+            if len(updates) >= limit:
+                upto_token = updates[-1][0]
+                limited = True
+
+            return updates, upto_token, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_new_device_messages", get_all_new_device_messages_txn
+        )
+
+
+class DeviceInboxBackgroundUpdateStore(SQLBaseStore):
+    DEVICE_INBOX_STREAM_ID = "device_inbox_stream_drop"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(DeviceInboxBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        self.db_pool.updates.register_background_index_update(
+            "device_inbox_stream_index",
+            index_name="device_inbox_stream_id_user_id",
+            table="device_inbox",
+            columns=["stream_id", "user_id"],
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            self.DEVICE_INBOX_STREAM_ID, self._background_drop_index_device_inbox
+        )
+
+    @defer.inlineCallbacks
+    def _background_drop_index_device_inbox(self, progress, batch_size):
+        def reindex_txn(conn):
+            txn = conn.cursor()
+            txn.execute("DROP INDEX IF EXISTS device_inbox_stream_id")
+            txn.close()
+
+        yield self.db_pool.runWithConnection(reindex_txn)
+
+        yield self.db_pool.updates._end_background_update(self.DEVICE_INBOX_STREAM_ID)
+
+        return 1
+
+
+class DeviceInboxStore(DeviceInboxWorkerStore, DeviceInboxBackgroundUpdateStore):
+    DEVICE_INBOX_STREAM_ID = "device_inbox_stream_drop"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(DeviceInboxStore, self).__init__(database, db_conn, hs)
+
+        # Map of (user_id, device_id) to the last stream_id that has been
+        # deleted up to. This is so that we can no op deletions.
+        self._last_device_delete_cache = ExpiringCache(
+            cache_name="last_device_delete_cache",
+            clock=self._clock,
+            max_len=10000,
+            expiry_ms=30 * 60 * 1000,
+        )
+
+    @trace
+    @defer.inlineCallbacks
+    def add_messages_to_device_inbox(
+        self, local_messages_by_user_then_device, remote_messages_by_destination
+    ):
+        """Used to send messages from this server.
+
+        Args:
+            sender_user_id(str): The ID of the user sending these messages.
+            local_messages_by_user_and_device(dict):
+                Dictionary of user_id to device_id to message.
+            remote_messages_by_destination(dict):
+                Dictionary of destination server_name to the EDU JSON to send.
+        Returns:
+            A deferred stream_id that resolves when the messages have been
+            inserted.
+        """
+
+        def add_messages_txn(txn, now_ms, stream_id):
+            # Add the local messages directly to the local inbox.
+            self._add_messages_to_local_device_inbox_txn(
+                txn, stream_id, local_messages_by_user_then_device
+            )
+
+            # Add the remote messages to the federation outbox.
+            # We'll send them to a remote server when we next send a
+            # federation transaction to that destination.
+            sql = (
+                "INSERT INTO device_federation_outbox"
+                " (destination, stream_id, queued_ts, messages_json)"
+                " VALUES (?,?,?,?)"
+            )
+            rows = []
+            for destination, edu in remote_messages_by_destination.items():
+                edu_json = json.dumps(edu)
+                rows.append((destination, stream_id, now_ms, edu_json))
+            txn.executemany(sql, rows)
+
+        with self._device_inbox_id_gen.get_next() as stream_id:
+            now_ms = self.clock.time_msec()
+            yield self.db_pool.runInteraction(
+                "add_messages_to_device_inbox", add_messages_txn, now_ms, stream_id
+            )
+            for user_id in local_messages_by_user_then_device.keys():
+                self._device_inbox_stream_cache.entity_has_changed(user_id, stream_id)
+            for destination in remote_messages_by_destination.keys():
+                self._device_federation_outbox_stream_cache.entity_has_changed(
+                    destination, stream_id
+                )
+
+        return self._device_inbox_id_gen.get_current_token()
+
+    @defer.inlineCallbacks
+    def add_messages_from_remote_to_device_inbox(
+        self, origin, message_id, local_messages_by_user_then_device
+    ):
+        def add_messages_txn(txn, now_ms, stream_id):
+            # Check if we've already inserted a matching message_id for that
+            # origin. This can happen if the origin doesn't receive our
+            # acknowledgement from the first time we received the message.
+            already_inserted = self.db_pool.simple_select_one_txn(
+                txn,
+                table="device_federation_inbox",
+                keyvalues={"origin": origin, "message_id": message_id},
+                retcols=("message_id",),
+                allow_none=True,
+            )
+            if already_inserted is not None:
+                return
+
+            # Add an entry for this message_id so that we know we've processed
+            # it.
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="device_federation_inbox",
+                values={
+                    "origin": origin,
+                    "message_id": message_id,
+                    "received_ts": now_ms,
+                },
+            )
+
+            # Add the messages to the approriate local device inboxes so that
+            # they'll be sent to the devices when they next sync.
+            self._add_messages_to_local_device_inbox_txn(
+                txn, stream_id, local_messages_by_user_then_device
+            )
+
+        with self._device_inbox_id_gen.get_next() as stream_id:
+            now_ms = self.clock.time_msec()
+            yield self.db_pool.runInteraction(
+                "add_messages_from_remote_to_device_inbox",
+                add_messages_txn,
+                now_ms,
+                stream_id,
+            )
+            for user_id in local_messages_by_user_then_device.keys():
+                self._device_inbox_stream_cache.entity_has_changed(user_id, stream_id)
+
+        return stream_id
+
+    def _add_messages_to_local_device_inbox_txn(
+        self, txn, stream_id, messages_by_user_then_device
+    ):
+        local_by_user_then_device = {}
+        for user_id, messages_by_device in messages_by_user_then_device.items():
+            messages_json_for_user = {}
+            devices = list(messages_by_device.keys())
+            if len(devices) == 1 and devices[0] == "*":
+                # Handle wildcard device_ids.
+                sql = "SELECT device_id FROM devices WHERE user_id = ?"
+                txn.execute(sql, (user_id,))
+                message_json = json.dumps(messages_by_device["*"])
+                for row in txn:
+                    # Add the message for all devices for this user on this
+                    # server.
+                    device = row[0]
+                    messages_json_for_user[device] = message_json
+            else:
+                if not devices:
+                    continue
+
+                clause, args = make_in_list_sql_clause(
+                    txn.database_engine, "device_id", devices
+                )
+                sql = "SELECT device_id FROM devices WHERE user_id = ? AND " + clause
+
+                # TODO: Maybe this needs to be done in batches if there are
+                # too many local devices for a given user.
+                txn.execute(sql, [user_id] + list(args))
+                for row in txn:
+                    # Only insert into the local inbox if the device exists on
+                    # this server
+                    device = row[0]
+                    message_json = json.dumps(messages_by_device[device])
+                    messages_json_for_user[device] = message_json
+
+            if messages_json_for_user:
+                local_by_user_then_device[user_id] = messages_json_for_user
+
+        if not local_by_user_then_device:
+            return
+
+        sql = (
+            "INSERT INTO device_inbox"
+            " (user_id, device_id, stream_id, message_json)"
+            " VALUES (?,?,?,?)"
+        )
+        rows = []
+        for user_id, messages_by_device in local_by_user_then_device.items():
+            for device_id, message_json in messages_by_device.items():
+                rows.append((user_id, device_id, stream_id, message_json))
+
+        txn.executemany(sql, rows)
diff --git a/synapse/storage/databases/main/devices.py b/synapse/storage/databases/main/devices.py
new file mode 100644
index 0000000000..88a7aadfc6
--- /dev/null
+++ b/synapse/storage/databases/main/devices.py
@@ -0,0 +1,1311 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+from typing import List, Optional, Set, Tuple
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.api.errors import Codes, StoreError
+from synapse.logging.opentracing import (
+    get_active_span_text_map,
+    set_tag,
+    trace,
+    whitelisted_homeserver,
+)
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
+from synapse.storage.database import (
+    DatabasePool,
+    LoggingTransaction,
+    make_tuple_comparison_clause,
+)
+from synapse.types import Collection, get_verify_key_from_cross_signing_key
+from synapse.util.caches.descriptors import (
+    Cache,
+    cached,
+    cachedInlineCallbacks,
+    cachedList,
+)
+from synapse.util.iterutils import batch_iter
+from synapse.util.stringutils import shortstr
+
+logger = logging.getLogger(__name__)
+
+DROP_DEVICE_LIST_STREAMS_NON_UNIQUE_INDEXES = (
+    "drop_device_list_streams_non_unique_indexes"
+)
+
+BG_UPDATE_REMOVE_DUP_OUTBOUND_POKES = "remove_dup_outbound_pokes"
+
+
+class DeviceWorkerStore(SQLBaseStore):
+    def get_device(self, user_id, device_id):
+        """Retrieve a device. Only returns devices that are not marked as
+        hidden.
+
+        Args:
+            user_id (str): The ID of the user which owns the device
+            device_id (str): The ID of the device to retrieve
+        Returns:
+            defer.Deferred for a dict containing the device information
+        Raises:
+            StoreError: if the device is not found
+        """
+        return self.db_pool.simple_select_one(
+            table="devices",
+            keyvalues={"user_id": user_id, "device_id": device_id, "hidden": False},
+            retcols=("user_id", "device_id", "display_name"),
+            desc="get_device",
+        )
+
+    @defer.inlineCallbacks
+    def get_devices_by_user(self, user_id):
+        """Retrieve all of a user's registered devices. Only returns devices
+        that are not marked as hidden.
+
+        Args:
+            user_id (str):
+        Returns:
+            defer.Deferred: resolves to a dict from device_id to a dict
+            containing "device_id", "user_id" and "display_name" for each
+            device.
+        """
+        devices = yield self.db_pool.simple_select_list(
+            table="devices",
+            keyvalues={"user_id": user_id, "hidden": False},
+            retcols=("user_id", "device_id", "display_name"),
+            desc="get_devices_by_user",
+        )
+
+        return {d["device_id"]: d for d in devices}
+
+    @trace
+    @defer.inlineCallbacks
+    def get_device_updates_by_remote(self, destination, from_stream_id, limit):
+        """Get a stream of device updates to send to the given remote server.
+
+        Args:
+            destination (str): The host the device updates are intended for
+            from_stream_id (int): The minimum stream_id to filter updates by, exclusive
+            limit (int): Maximum number of device updates to return
+        Returns:
+            Deferred[tuple[int, list[tuple[string,dict]]]]:
+                current stream id (ie, the stream id of the last update included in the
+                response), and the list of updates, where each update is a pair of EDU
+                type and EDU contents
+        """
+        now_stream_id = self._device_list_id_gen.get_current_token()
+
+        has_changed = self._device_list_federation_stream_cache.has_entity_changed(
+            destination, int(from_stream_id)
+        )
+        if not has_changed:
+            return now_stream_id, []
+
+        updates = yield self.db_pool.runInteraction(
+            "get_device_updates_by_remote",
+            self._get_device_updates_by_remote_txn,
+            destination,
+            from_stream_id,
+            now_stream_id,
+            limit,
+        )
+
+        # Return an empty list if there are no updates
+        if not updates:
+            return now_stream_id, []
+
+        # get the cross-signing keys of the users in the list, so that we can
+        # determine which of the device changes were cross-signing keys
+        users = {r[0] for r in updates}
+        master_key_by_user = {}
+        self_signing_key_by_user = {}
+        for user in users:
+            cross_signing_key = yield self.get_e2e_cross_signing_key(user, "master")
+            if cross_signing_key:
+                key_id, verify_key = get_verify_key_from_cross_signing_key(
+                    cross_signing_key
+                )
+                # verify_key is a VerifyKey from signedjson, which uses
+                # .version to denote the portion of the key ID after the
+                # algorithm and colon, which is the device ID
+                master_key_by_user[user] = {
+                    "key_info": cross_signing_key,
+                    "device_id": verify_key.version,
+                }
+
+            cross_signing_key = yield self.get_e2e_cross_signing_key(
+                user, "self_signing"
+            )
+            if cross_signing_key:
+                key_id, verify_key = get_verify_key_from_cross_signing_key(
+                    cross_signing_key
+                )
+                self_signing_key_by_user[user] = {
+                    "key_info": cross_signing_key,
+                    "device_id": verify_key.version,
+                }
+
+        # Perform the equivalent of a GROUP BY
+        #
+        # Iterate through the updates list and copy non-duplicate
+        # (user_id, device_id) entries into a map, with the value being
+        # the max stream_id across each set of duplicate entries
+        #
+        # maps (user_id, device_id) -> (stream_id, opentracing_context)
+        #
+        # opentracing_context contains the opentracing metadata for the request
+        # that created the poke
+        #
+        # The most recent request's opentracing_context is used as the
+        # context which created the Edu.
+
+        query_map = {}
+        cross_signing_keys_by_user = {}
+        for user_id, device_id, update_stream_id, update_context in updates:
+            if (
+                user_id in master_key_by_user
+                and device_id == master_key_by_user[user_id]["device_id"]
+            ):
+                result = cross_signing_keys_by_user.setdefault(user_id, {})
+                result["master_key"] = master_key_by_user[user_id]["key_info"]
+            elif (
+                user_id in self_signing_key_by_user
+                and device_id == self_signing_key_by_user[user_id]["device_id"]
+            ):
+                result = cross_signing_keys_by_user.setdefault(user_id, {})
+                result["self_signing_key"] = self_signing_key_by_user[user_id][
+                    "key_info"
+                ]
+            else:
+                key = (user_id, device_id)
+
+                previous_update_stream_id, _ = query_map.get(key, (0, None))
+
+                if update_stream_id > previous_update_stream_id:
+                    query_map[key] = (update_stream_id, update_context)
+
+        results = yield self._get_device_update_edus_by_remote(
+            destination, from_stream_id, query_map
+        )
+
+        # add the updated cross-signing keys to the results list
+        for user_id, result in cross_signing_keys_by_user.items():
+            result["user_id"] = user_id
+            # FIXME: switch to m.signing_key_update when MSC1756 is merged into the spec
+            results.append(("org.matrix.signing_key_update", result))
+
+        return now_stream_id, results
+
+    def _get_device_updates_by_remote_txn(
+        self, txn, destination, from_stream_id, now_stream_id, limit
+    ):
+        """Return device update information for a given remote destination
+
+        Args:
+            txn (LoggingTransaction): The transaction to execute
+            destination (str): The host the device updates are intended for
+            from_stream_id (int): The minimum stream_id to filter updates by, exclusive
+            now_stream_id (int): The maximum stream_id to filter updates by, inclusive
+            limit (int): Maximum number of device updates to return
+
+        Returns:
+            List: List of device updates
+        """
+        # get the list of device updates that need to be sent
+        sql = """
+            SELECT user_id, device_id, stream_id, opentracing_context FROM device_lists_outbound_pokes
+            WHERE destination = ? AND ? < stream_id AND stream_id <= ?
+            ORDER BY stream_id
+            LIMIT ?
+        """
+        txn.execute(sql, (destination, from_stream_id, now_stream_id, limit))
+
+        return list(txn)
+
+    @defer.inlineCallbacks
+    def _get_device_update_edus_by_remote(self, destination, from_stream_id, query_map):
+        """Returns a list of device update EDUs as well as E2EE keys
+
+        Args:
+            destination (str): The host the device updates are intended for
+            from_stream_id (int): The minimum stream_id to filter updates by, exclusive
+            query_map (Dict[(str, str): (int, str|None)]): Dictionary mapping
+                user_id/device_id to update stream_id and the relevent json-encoded
+                opentracing context
+
+        Returns:
+            List[Dict]: List of objects representing an device update EDU
+
+        """
+        devices = (
+            yield self.db_pool.runInteraction(
+                "_get_e2e_device_keys_txn",
+                self._get_e2e_device_keys_txn,
+                query_map.keys(),
+                include_all_devices=True,
+                include_deleted_devices=True,
+            )
+            if query_map
+            else {}
+        )
+
+        results = []
+        for user_id, user_devices in devices.items():
+            # The prev_id for the first row is always the last row before
+            # `from_stream_id`
+            prev_id = yield self._get_last_device_update_for_remote_user(
+                destination, user_id, from_stream_id
+            )
+
+            # make sure we go through the devices in stream order
+            device_ids = sorted(
+                user_devices.keys(), key=lambda i: query_map[(user_id, i)][0],
+            )
+
+            for device_id in device_ids:
+                device = user_devices[device_id]
+                stream_id, opentracing_context = query_map[(user_id, device_id)]
+                result = {
+                    "user_id": user_id,
+                    "device_id": device_id,
+                    "prev_id": [prev_id] if prev_id else [],
+                    "stream_id": stream_id,
+                    "org.matrix.opentracing_context": opentracing_context,
+                }
+
+                prev_id = stream_id
+
+                if device is not None:
+                    key_json = device.get("key_json", None)
+                    if key_json:
+                        result["keys"] = db_to_json(key_json)
+
+                        if "signatures" in device:
+                            for sig_user_id, sigs in device["signatures"].items():
+                                result["keys"].setdefault("signatures", {}).setdefault(
+                                    sig_user_id, {}
+                                ).update(sigs)
+
+                    device_display_name = device.get("device_display_name", None)
+                    if device_display_name:
+                        result["device_display_name"] = device_display_name
+                else:
+                    result["deleted"] = True
+
+                results.append(("m.device_list_update", result))
+
+        return results
+
+    def _get_last_device_update_for_remote_user(
+        self, destination, user_id, from_stream_id
+    ):
+        def f(txn):
+            prev_sent_id_sql = """
+                SELECT coalesce(max(stream_id), 0) as stream_id
+                FROM device_lists_outbound_last_success
+                WHERE destination = ? AND user_id = ? AND stream_id <= ?
+            """
+            txn.execute(prev_sent_id_sql, (destination, user_id, from_stream_id))
+            rows = txn.fetchall()
+            return rows[0][0]
+
+        return self.db_pool.runInteraction("get_last_device_update_for_remote_user", f)
+
+    def mark_as_sent_devices_by_remote(self, destination, stream_id):
+        """Mark that updates have successfully been sent to the destination.
+        """
+        return self.db_pool.runInteraction(
+            "mark_as_sent_devices_by_remote",
+            self._mark_as_sent_devices_by_remote_txn,
+            destination,
+            stream_id,
+        )
+
+    def _mark_as_sent_devices_by_remote_txn(self, txn, destination, stream_id):
+        # We update the device_lists_outbound_last_success with the successfully
+        # poked users.
+        sql = """
+            SELECT user_id, coalesce(max(o.stream_id), 0)
+            FROM device_lists_outbound_pokes as o
+            WHERE destination = ? AND o.stream_id <= ?
+            GROUP BY user_id
+        """
+        txn.execute(sql, (destination, stream_id))
+        rows = txn.fetchall()
+
+        self.db_pool.simple_upsert_many_txn(
+            txn=txn,
+            table="device_lists_outbound_last_success",
+            key_names=("destination", "user_id"),
+            key_values=((destination, user_id) for user_id, _ in rows),
+            value_names=("stream_id",),
+            value_values=((stream_id,) for _, stream_id in rows),
+        )
+
+        # Delete all sent outbound pokes
+        sql = """
+            DELETE FROM device_lists_outbound_pokes
+            WHERE destination = ? AND stream_id <= ?
+        """
+        txn.execute(sql, (destination, stream_id))
+
+    @defer.inlineCallbacks
+    def add_user_signature_change_to_streams(self, from_user_id, user_ids):
+        """Persist that a user has made new signatures
+
+        Args:
+            from_user_id (str): the user who made the signatures
+            user_ids (list[str]): the users who were signed
+        """
+
+        with self._device_list_id_gen.get_next() as stream_id:
+            yield self.db_pool.runInteraction(
+                "add_user_sig_change_to_streams",
+                self._add_user_signature_change_txn,
+                from_user_id,
+                user_ids,
+                stream_id,
+            )
+        return stream_id
+
+    def _add_user_signature_change_txn(self, txn, from_user_id, user_ids, stream_id):
+        txn.call_after(
+            self._user_signature_stream_cache.entity_has_changed,
+            from_user_id,
+            stream_id,
+        )
+        self.db_pool.simple_insert_txn(
+            txn,
+            "user_signature_stream",
+            values={
+                "stream_id": stream_id,
+                "from_user_id": from_user_id,
+                "user_ids": json.dumps(user_ids),
+            },
+        )
+
+    def get_device_stream_token(self):
+        return self._device_list_id_gen.get_current_token()
+
+    @trace
+    @defer.inlineCallbacks
+    def get_user_devices_from_cache(self, query_list):
+        """Get the devices (and keys if any) for remote users from the cache.
+
+        Args:
+            query_list(list): List of (user_id, device_ids), if device_ids is
+                falsey then return all device ids for that user.
+
+        Returns:
+            (user_ids_not_in_cache, results_map), where user_ids_not_in_cache is
+            a set of user_ids and results_map is a mapping of
+            user_id -> device_id -> device_info
+        """
+        user_ids = {user_id for user_id, _ in query_list}
+        user_map = yield self.get_device_list_last_stream_id_for_remotes(list(user_ids))
+
+        # We go and check if any of the users need to have their device lists
+        # resynced. If they do then we remove them from the cached list.
+        users_needing_resync = yield self.get_user_ids_requiring_device_list_resync(
+            user_ids
+        )
+        user_ids_in_cache = {
+            user_id for user_id, stream_id in user_map.items() if stream_id
+        } - users_needing_resync
+        user_ids_not_in_cache = user_ids - user_ids_in_cache
+
+        results = {}
+        for user_id, device_id in query_list:
+            if user_id not in user_ids_in_cache:
+                continue
+
+            if device_id:
+                device = yield self._get_cached_user_device(user_id, device_id)
+                results.setdefault(user_id, {})[device_id] = device
+            else:
+                results[user_id] = yield self.get_cached_devices_for_user(user_id)
+
+        set_tag("in_cache", results)
+        set_tag("not_in_cache", user_ids_not_in_cache)
+
+        return user_ids_not_in_cache, results
+
+    @cachedInlineCallbacks(num_args=2, tree=True)
+    def _get_cached_user_device(self, user_id, device_id):
+        content = yield self.db_pool.simple_select_one_onecol(
+            table="device_lists_remote_cache",
+            keyvalues={"user_id": user_id, "device_id": device_id},
+            retcol="content",
+            desc="_get_cached_user_device",
+        )
+        return db_to_json(content)
+
+    @cachedInlineCallbacks()
+    def get_cached_devices_for_user(self, user_id):
+        devices = yield self.db_pool.simple_select_list(
+            table="device_lists_remote_cache",
+            keyvalues={"user_id": user_id},
+            retcols=("device_id", "content"),
+            desc="get_cached_devices_for_user",
+        )
+        return {
+            device["device_id"]: db_to_json(device["content"]) for device in devices
+        }
+
+    def get_devices_with_keys_by_user(self, user_id):
+        """Get all devices (with any device keys) for a user
+
+        Returns:
+            (stream_id, devices)
+        """
+        return self.db_pool.runInteraction(
+            "get_devices_with_keys_by_user",
+            self._get_devices_with_keys_by_user_txn,
+            user_id,
+        )
+
+    def _get_devices_with_keys_by_user_txn(self, txn, user_id):
+        now_stream_id = self._device_list_id_gen.get_current_token()
+
+        devices = self._get_e2e_device_keys_txn(
+            txn, [(user_id, None)], include_all_devices=True
+        )
+
+        if devices:
+            user_devices = devices[user_id]
+            results = []
+            for device_id, device in user_devices.items():
+                result = {"device_id": device_id}
+
+                key_json = device.get("key_json", None)
+                if key_json:
+                    result["keys"] = db_to_json(key_json)
+
+                    if "signatures" in device:
+                        for sig_user_id, sigs in device["signatures"].items():
+                            result["keys"].setdefault("signatures", {}).setdefault(
+                                sig_user_id, {}
+                            ).update(sigs)
+
+                device_display_name = device.get("device_display_name", None)
+                if device_display_name:
+                    result["device_display_name"] = device_display_name
+
+                results.append(result)
+
+            return now_stream_id, results
+
+        return now_stream_id, []
+
+    def get_users_whose_devices_changed(self, from_key, user_ids):
+        """Get set of users whose devices have changed since `from_key` that
+        are in the given list of user_ids.
+
+        Args:
+            from_key (str): The device lists stream token
+            user_ids (Iterable[str])
+
+        Returns:
+            Deferred[set[str]]: The set of user_ids whose devices have changed
+            since `from_key`
+        """
+        from_key = int(from_key)
+
+        # Get set of users who *may* have changed. Users not in the returned
+        # list have definitely not changed.
+        to_check = self._device_list_stream_cache.get_entities_changed(
+            user_ids, from_key
+        )
+
+        if not to_check:
+            return defer.succeed(set())
+
+        def _get_users_whose_devices_changed_txn(txn):
+            changes = set()
+
+            sql = """
+                SELECT DISTINCT user_id FROM device_lists_stream
+                WHERE stream_id > ?
+                AND
+            """
+
+            for chunk in batch_iter(to_check, 100):
+                clause, args = make_in_list_sql_clause(
+                    txn.database_engine, "user_id", chunk
+                )
+                txn.execute(sql + clause, (from_key,) + tuple(args))
+                changes.update(user_id for user_id, in txn)
+
+            return changes
+
+        return self.db_pool.runInteraction(
+            "get_users_whose_devices_changed", _get_users_whose_devices_changed_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_users_whose_signatures_changed(self, user_id, from_key):
+        """Get the users who have new cross-signing signatures made by `user_id` since
+        `from_key`.
+
+        Args:
+            user_id (str): the user who made the signatures
+            from_key (str): The device lists stream token
+        """
+        from_key = int(from_key)
+        if self._user_signature_stream_cache.has_entity_changed(user_id, from_key):
+            sql = """
+                SELECT DISTINCT user_ids FROM user_signature_stream
+                WHERE from_user_id = ? AND stream_id > ?
+            """
+            rows = yield self.db_pool.execute(
+                "get_users_whose_signatures_changed", None, sql, user_id, from_key
+            )
+            return {user for row in rows for user in db_to_json(row[0])}
+        else:
+            return set()
+
+    async def get_all_device_list_changes_for_remotes(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for device lists replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def _get_all_device_list_changes_for_remotes(txn):
+            # This query Does The Right Thing where it'll correctly apply the
+            # bounds to the inner queries.
+            sql = """
+                SELECT stream_id, entity FROM (
+                    SELECT stream_id, user_id AS entity FROM device_lists_stream
+                    UNION ALL
+                    SELECT stream_id, destination AS entity FROM device_lists_outbound_pokes
+                ) AS e
+                WHERE ? < stream_id AND stream_id <= ?
+                LIMIT ?
+            """
+
+            txn.execute(sql, (last_id, current_id, limit))
+            updates = [(row[0], row[1:]) for row in txn]
+            limited = False
+            upto_token = current_id
+            if len(updates) >= limit:
+                upto_token = updates[-1][0]
+                limited = True
+
+            return updates, upto_token, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_device_list_changes_for_remotes",
+            _get_all_device_list_changes_for_remotes,
+        )
+
+    @cached(max_entries=10000)
+    def get_device_list_last_stream_id_for_remote(self, user_id):
+        """Get the last stream_id we got for a user. May be None if we haven't
+        got any information for them.
+        """
+        return self.db_pool.simple_select_one_onecol(
+            table="device_lists_remote_extremeties",
+            keyvalues={"user_id": user_id},
+            retcol="stream_id",
+            desc="get_device_list_last_stream_id_for_remote",
+            allow_none=True,
+        )
+
+    @cachedList(
+        cached_method_name="get_device_list_last_stream_id_for_remote",
+        list_name="user_ids",
+        inlineCallbacks=True,
+    )
+    def get_device_list_last_stream_id_for_remotes(self, user_ids):
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="device_lists_remote_extremeties",
+            column="user_id",
+            iterable=user_ids,
+            retcols=("user_id", "stream_id"),
+            desc="get_device_list_last_stream_id_for_remotes",
+        )
+
+        results = {user_id: None for user_id in user_ids}
+        results.update({row["user_id"]: row["stream_id"] for row in rows})
+
+        return results
+
+    @defer.inlineCallbacks
+    def get_user_ids_requiring_device_list_resync(
+        self, user_ids: Optional[Collection[str]] = None,
+    ) -> Set[str]:
+        """Given a list of remote users return the list of users that we
+        should resync the device lists for. If None is given instead of a list,
+        return every user that we should resync the device lists for.
+
+        Returns:
+            The IDs of users whose device lists need resync.
+        """
+        if user_ids:
+            rows = yield self.db_pool.simple_select_many_batch(
+                table="device_lists_remote_resync",
+                column="user_id",
+                iterable=user_ids,
+                retcols=("user_id",),
+                desc="get_user_ids_requiring_device_list_resync_with_iterable",
+            )
+        else:
+            rows = yield self.db_pool.simple_select_list(
+                table="device_lists_remote_resync",
+                keyvalues=None,
+                retcols=("user_id",),
+                desc="get_user_ids_requiring_device_list_resync",
+            )
+
+        return {row["user_id"] for row in rows}
+
+    def mark_remote_user_device_cache_as_stale(self, user_id: str):
+        """Records that the server has reason to believe the cache of the devices
+        for the remote users is out of date.
+        """
+        return self.db_pool.simple_upsert(
+            table="device_lists_remote_resync",
+            keyvalues={"user_id": user_id},
+            values={},
+            insertion_values={"added_ts": self._clock.time_msec()},
+            desc="make_remote_user_device_cache_as_stale",
+        )
+
+    def mark_remote_user_device_list_as_unsubscribed(self, user_id):
+        """Mark that we no longer track device lists for remote user.
+        """
+
+        def _mark_remote_user_device_list_as_unsubscribed_txn(txn):
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="device_lists_remote_extremeties",
+                keyvalues={"user_id": user_id},
+            )
+            self._invalidate_cache_and_stream(
+                txn, self.get_device_list_last_stream_id_for_remote, (user_id,)
+            )
+
+        return self.db_pool.runInteraction(
+            "mark_remote_user_device_list_as_unsubscribed",
+            _mark_remote_user_device_list_as_unsubscribed_txn,
+        )
+
+
+class DeviceBackgroundUpdateStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(DeviceBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        self.db_pool.updates.register_background_index_update(
+            "device_lists_stream_idx",
+            index_name="device_lists_stream_user_id",
+            table="device_lists_stream",
+            columns=["user_id", "device_id"],
+        )
+
+        # create a unique index on device_lists_remote_cache
+        self.db_pool.updates.register_background_index_update(
+            "device_lists_remote_cache_unique_idx",
+            index_name="device_lists_remote_cache_unique_id",
+            table="device_lists_remote_cache",
+            columns=["user_id", "device_id"],
+            unique=True,
+        )
+
+        # And one on device_lists_remote_extremeties
+        self.db_pool.updates.register_background_index_update(
+            "device_lists_remote_extremeties_unique_idx",
+            index_name="device_lists_remote_extremeties_unique_idx",
+            table="device_lists_remote_extremeties",
+            columns=["user_id"],
+            unique=True,
+        )
+
+        # once they complete, we can remove the old non-unique indexes.
+        self.db_pool.updates.register_background_update_handler(
+            DROP_DEVICE_LIST_STREAMS_NON_UNIQUE_INDEXES,
+            self._drop_device_list_streams_non_unique_indexes,
+        )
+
+        # clear out duplicate device list outbound pokes
+        self.db_pool.updates.register_background_update_handler(
+            BG_UPDATE_REMOVE_DUP_OUTBOUND_POKES, self._remove_duplicate_outbound_pokes,
+        )
+
+        # a pair of background updates that were added during the 1.14 release cycle,
+        # but replaced with 58/06dlols_unique_idx.py
+        self.db_pool.updates.register_noop_background_update(
+            "device_lists_outbound_last_success_unique_idx",
+        )
+        self.db_pool.updates.register_noop_background_update(
+            "drop_device_lists_outbound_last_success_non_unique_idx",
+        )
+
+    @defer.inlineCallbacks
+    def _drop_device_list_streams_non_unique_indexes(self, progress, batch_size):
+        def f(conn):
+            txn = conn.cursor()
+            txn.execute("DROP INDEX IF EXISTS device_lists_remote_cache_id")
+            txn.execute("DROP INDEX IF EXISTS device_lists_remote_extremeties_id")
+            txn.close()
+
+        yield self.db_pool.runWithConnection(f)
+        yield self.db_pool.updates._end_background_update(
+            DROP_DEVICE_LIST_STREAMS_NON_UNIQUE_INDEXES
+        )
+        return 1
+
+    async def _remove_duplicate_outbound_pokes(self, progress, batch_size):
+        # for some reason, we have accumulated duplicate entries in
+        # device_lists_outbound_pokes, which makes prune_outbound_device_list_pokes less
+        # efficient.
+        #
+        # For each duplicate, we delete all the existing rows and put one back.
+
+        KEY_COLS = ["stream_id", "destination", "user_id", "device_id"]
+        last_row = progress.get(
+            "last_row",
+            {"stream_id": 0, "destination": "", "user_id": "", "device_id": ""},
+        )
+
+        def _txn(txn):
+            clause, args = make_tuple_comparison_clause(
+                self.db_pool.engine, [(x, last_row[x]) for x in KEY_COLS]
+            )
+            sql = """
+                SELECT stream_id, destination, user_id, device_id, MAX(ts) AS ts
+                FROM device_lists_outbound_pokes
+                WHERE %s
+                GROUP BY %s
+                HAVING count(*) > 1
+                ORDER BY %s
+                LIMIT ?
+                """ % (
+                clause,  # WHERE
+                ",".join(KEY_COLS),  # GROUP BY
+                ",".join(KEY_COLS),  # ORDER BY
+            )
+            txn.execute(sql, args + [batch_size])
+            rows = self.db_pool.cursor_to_dict(txn)
+
+            row = None
+            for row in rows:
+                self.db_pool.simple_delete_txn(
+                    txn, "device_lists_outbound_pokes", {x: row[x] for x in KEY_COLS},
+                )
+
+                row["sent"] = False
+                self.db_pool.simple_insert_txn(
+                    txn, "device_lists_outbound_pokes", row,
+                )
+
+            if row:
+                self.db_pool.updates._background_update_progress_txn(
+                    txn, BG_UPDATE_REMOVE_DUP_OUTBOUND_POKES, {"last_row": row},
+                )
+
+            return len(rows)
+
+        rows = await self.db_pool.runInteraction(
+            BG_UPDATE_REMOVE_DUP_OUTBOUND_POKES, _txn
+        )
+
+        if not rows:
+            await self.db_pool.updates._end_background_update(
+                BG_UPDATE_REMOVE_DUP_OUTBOUND_POKES
+            )
+
+        return rows
+
+
+class DeviceStore(DeviceWorkerStore, DeviceBackgroundUpdateStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(DeviceStore, self).__init__(database, db_conn, hs)
+
+        # Map of (user_id, device_id) -> bool. If there is an entry that implies
+        # the device exists.
+        self.device_id_exists_cache = Cache(
+            name="device_id_exists", keylen=2, max_entries=10000
+        )
+
+        self._clock.looping_call(self._prune_old_outbound_device_pokes, 60 * 60 * 1000)
+
+    @defer.inlineCallbacks
+    def store_device(self, user_id, device_id, initial_device_display_name):
+        """Ensure the given device is known; add it to the store if not
+
+        Args:
+            user_id (str): id of user associated with the device
+            device_id (str): id of device
+            initial_device_display_name (str): initial displayname of the
+               device. Ignored if device exists.
+        Returns:
+            defer.Deferred: boolean whether the device was inserted or an
+                existing device existed with that ID.
+        Raises:
+            StoreError: if the device is already in use
+        """
+        key = (user_id, device_id)
+        if self.device_id_exists_cache.get(key, None):
+            return False
+
+        try:
+            inserted = yield self.db_pool.simple_insert(
+                "devices",
+                values={
+                    "user_id": user_id,
+                    "device_id": device_id,
+                    "display_name": initial_device_display_name,
+                    "hidden": False,
+                },
+                desc="store_device",
+                or_ignore=True,
+            )
+            if not inserted:
+                # if the device already exists, check if it's a real device, or
+                # if the device ID is reserved by something else
+                hidden = yield self.db_pool.simple_select_one_onecol(
+                    "devices",
+                    keyvalues={"user_id": user_id, "device_id": device_id},
+                    retcol="hidden",
+                )
+                if hidden:
+                    raise StoreError(400, "The device ID is in use", Codes.FORBIDDEN)
+            self.device_id_exists_cache.prefill(key, True)
+            return inserted
+        except StoreError:
+            raise
+        except Exception as e:
+            logger.error(
+                "store_device with device_id=%s(%r) user_id=%s(%r)"
+                " display_name=%s(%r) failed: %s",
+                type(device_id).__name__,
+                device_id,
+                type(user_id).__name__,
+                user_id,
+                type(initial_device_display_name).__name__,
+                initial_device_display_name,
+                e,
+            )
+            raise StoreError(500, "Problem storing device.")
+
+    @defer.inlineCallbacks
+    def delete_device(self, user_id, device_id):
+        """Delete a device.
+
+        Args:
+            user_id (str): The ID of the user which owns the device
+            device_id (str): The ID of the device to delete
+        Returns:
+            defer.Deferred
+        """
+        yield self.db_pool.simple_delete_one(
+            table="devices",
+            keyvalues={"user_id": user_id, "device_id": device_id, "hidden": False},
+            desc="delete_device",
+        )
+
+        self.device_id_exists_cache.invalidate((user_id, device_id))
+
+    @defer.inlineCallbacks
+    def delete_devices(self, user_id, device_ids):
+        """Deletes several devices.
+
+        Args:
+            user_id (str): The ID of the user which owns the devices
+            device_ids (list): The IDs of the devices to delete
+        Returns:
+            defer.Deferred
+        """
+        yield self.db_pool.simple_delete_many(
+            table="devices",
+            column="device_id",
+            iterable=device_ids,
+            keyvalues={"user_id": user_id, "hidden": False},
+            desc="delete_devices",
+        )
+        for device_id in device_ids:
+            self.device_id_exists_cache.invalidate((user_id, device_id))
+
+    def update_device(self, user_id, device_id, new_display_name=None):
+        """Update a device. Only updates the device if it is not marked as
+        hidden.
+
+        Args:
+            user_id (str): The ID of the user which owns the device
+            device_id (str): The ID of the device to update
+            new_display_name (str|None): new displayname for device; None
+               to leave unchanged
+        Raises:
+            StoreError: if the device is not found
+        Returns:
+            defer.Deferred
+        """
+        updates = {}
+        if new_display_name is not None:
+            updates["display_name"] = new_display_name
+        if not updates:
+            return defer.succeed(None)
+        return self.db_pool.simple_update_one(
+            table="devices",
+            keyvalues={"user_id": user_id, "device_id": device_id, "hidden": False},
+            updatevalues=updates,
+            desc="update_device",
+        )
+
+    def update_remote_device_list_cache_entry(
+        self, user_id, device_id, content, stream_id
+    ):
+        """Updates a single device in the cache of a remote user's devicelist.
+
+        Note: assumes that we are the only thread that can be updating this user's
+        device list.
+
+        Args:
+            user_id (str): User to update device list for
+            device_id (str): ID of decivice being updated
+            content (dict): new data on this device
+            stream_id (int): the version of the device list
+
+        Returns:
+            Deferred[None]
+        """
+        return self.db_pool.runInteraction(
+            "update_remote_device_list_cache_entry",
+            self._update_remote_device_list_cache_entry_txn,
+            user_id,
+            device_id,
+            content,
+            stream_id,
+        )
+
+    def _update_remote_device_list_cache_entry_txn(
+        self, txn, user_id, device_id, content, stream_id
+    ):
+        if content.get("deleted"):
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="device_lists_remote_cache",
+                keyvalues={"user_id": user_id, "device_id": device_id},
+            )
+
+            txn.call_after(self.device_id_exists_cache.invalidate, (user_id, device_id))
+        else:
+            self.db_pool.simple_upsert_txn(
+                txn,
+                table="device_lists_remote_cache",
+                keyvalues={"user_id": user_id, "device_id": device_id},
+                values={"content": json.dumps(content)},
+                # we don't need to lock, because we assume we are the only thread
+                # updating this user's devices.
+                lock=False,
+            )
+
+        txn.call_after(self._get_cached_user_device.invalidate, (user_id, device_id))
+        txn.call_after(self.get_cached_devices_for_user.invalidate, (user_id,))
+        txn.call_after(
+            self.get_device_list_last_stream_id_for_remote.invalidate, (user_id,)
+        )
+
+        self.db_pool.simple_upsert_txn(
+            txn,
+            table="device_lists_remote_extremeties",
+            keyvalues={"user_id": user_id},
+            values={"stream_id": stream_id},
+            # again, we can assume we are the only thread updating this user's
+            # extremity.
+            lock=False,
+        )
+
+    def update_remote_device_list_cache(self, user_id, devices, stream_id):
+        """Replace the entire cache of the remote user's devices.
+
+        Note: assumes that we are the only thread that can be updating this user's
+        device list.
+
+        Args:
+            user_id (str): User to update device list for
+            devices (list[dict]): list of device objects supplied over federation
+            stream_id (int): the version of the device list
+
+        Returns:
+            Deferred[None]
+        """
+        return self.db_pool.runInteraction(
+            "update_remote_device_list_cache",
+            self._update_remote_device_list_cache_txn,
+            user_id,
+            devices,
+            stream_id,
+        )
+
+    def _update_remote_device_list_cache_txn(self, txn, user_id, devices, stream_id):
+        self.db_pool.simple_delete_txn(
+            txn, table="device_lists_remote_cache", keyvalues={"user_id": user_id}
+        )
+
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="device_lists_remote_cache",
+            values=[
+                {
+                    "user_id": user_id,
+                    "device_id": content["device_id"],
+                    "content": json.dumps(content),
+                }
+                for content in devices
+            ],
+        )
+
+        txn.call_after(self.get_cached_devices_for_user.invalidate, (user_id,))
+        txn.call_after(self._get_cached_user_device.invalidate_many, (user_id,))
+        txn.call_after(
+            self.get_device_list_last_stream_id_for_remote.invalidate, (user_id,)
+        )
+
+        self.db_pool.simple_upsert_txn(
+            txn,
+            table="device_lists_remote_extremeties",
+            keyvalues={"user_id": user_id},
+            values={"stream_id": stream_id},
+            # we don't need to lock, because we can assume we are the only thread
+            # updating this user's extremity.
+            lock=False,
+        )
+
+        # If we're replacing the remote user's device list cache presumably
+        # we've done a full resync, so we remove the entry that says we need
+        # to resync
+        self.db_pool.simple_delete_txn(
+            txn, table="device_lists_remote_resync", keyvalues={"user_id": user_id},
+        )
+
+    @defer.inlineCallbacks
+    def add_device_change_to_streams(self, user_id, device_ids, hosts):
+        """Persist that a user's devices have been updated, and which hosts
+        (if any) should be poked.
+        """
+        if not device_ids:
+            return
+
+        with self._device_list_id_gen.get_next_mult(len(device_ids)) as stream_ids:
+            yield self.db_pool.runInteraction(
+                "add_device_change_to_stream",
+                self._add_device_change_to_stream_txn,
+                user_id,
+                device_ids,
+                stream_ids,
+            )
+
+        if not hosts:
+            return stream_ids[-1]
+
+        context = get_active_span_text_map()
+        with self._device_list_id_gen.get_next_mult(
+            len(hosts) * len(device_ids)
+        ) as stream_ids:
+            yield self.db_pool.runInteraction(
+                "add_device_outbound_poke_to_stream",
+                self._add_device_outbound_poke_to_stream_txn,
+                user_id,
+                device_ids,
+                hosts,
+                stream_ids,
+                context,
+            )
+
+        return stream_ids[-1]
+
+    def _add_device_change_to_stream_txn(
+        self,
+        txn: LoggingTransaction,
+        user_id: str,
+        device_ids: Collection[str],
+        stream_ids: List[str],
+    ):
+        txn.call_after(
+            self._device_list_stream_cache.entity_has_changed, user_id, stream_ids[-1],
+        )
+
+        min_stream_id = stream_ids[0]
+
+        # Delete older entries in the table, as we really only care about
+        # when the latest change happened.
+        txn.executemany(
+            """
+            DELETE FROM device_lists_stream
+            WHERE user_id = ? AND device_id = ? AND stream_id < ?
+            """,
+            [(user_id, device_id, min_stream_id) for device_id in device_ids],
+        )
+
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="device_lists_stream",
+            values=[
+                {"stream_id": stream_id, "user_id": user_id, "device_id": device_id}
+                for stream_id, device_id in zip(stream_ids, device_ids)
+            ],
+        )
+
+    def _add_device_outbound_poke_to_stream_txn(
+        self, txn, user_id, device_ids, hosts, stream_ids, context,
+    ):
+        for host in hosts:
+            txn.call_after(
+                self._device_list_federation_stream_cache.entity_has_changed,
+                host,
+                stream_ids[-1],
+            )
+
+        now = self._clock.time_msec()
+        next_stream_id = iter(stream_ids)
+
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="device_lists_outbound_pokes",
+            values=[
+                {
+                    "destination": destination,
+                    "stream_id": next(next_stream_id),
+                    "user_id": user_id,
+                    "device_id": device_id,
+                    "sent": False,
+                    "ts": now,
+                    "opentracing_context": json.dumps(context)
+                    if whitelisted_homeserver(destination)
+                    else "{}",
+                }
+                for destination in hosts
+                for device_id in device_ids
+            ],
+        )
+
+    def _prune_old_outbound_device_pokes(self, prune_age=24 * 60 * 60 * 1000):
+        """Delete old entries out of the device_lists_outbound_pokes to ensure
+        that we don't fill up due to dead servers.
+
+        Normally, we try to send device updates as a delta since a previous known point:
+        this is done by setting the prev_id in the m.device_list_update EDU. However,
+        for that to work, we have to have a complete record of each change to
+        each device, which can add up to quite a lot of data.
+
+        An alternative mechanism is that, if the remote server sees that it has missed
+        an entry in the stream_id sequence for a given user, it will request a full
+        list of that user's devices. Hence, we can reduce the amount of data we have to
+        store (and transmit in some future transaction), by clearing almost everything
+        for a given destination out of the database, and having the remote server
+        resync.
+
+        All we need to do is make sure we keep at least one row for each
+        (user, destination) pair, to remind us to send a m.device_list_update EDU for
+        that user when the destination comes back. It doesn't matter which device
+        we keep.
+        """
+        yesterday = self._clock.time_msec() - prune_age
+
+        def _prune_txn(txn):
+            # look for (user, destination) pairs which have an update older than
+            # the cutoff.
+            #
+            # For each pair, we also need to know the most recent stream_id, and
+            # an arbitrary device_id at that stream_id.
+            select_sql = """
+            SELECT
+                dlop1.destination,
+                dlop1.user_id,
+                MAX(dlop1.stream_id) AS stream_id,
+                (SELECT MIN(dlop2.device_id) AS device_id FROM
+                    device_lists_outbound_pokes dlop2
+                    WHERE dlop2.destination = dlop1.destination AND
+                      dlop2.user_id=dlop1.user_id AND
+                      dlop2.stream_id=MAX(dlop1.stream_id)
+                )
+            FROM device_lists_outbound_pokes dlop1
+                GROUP BY destination, user_id
+                HAVING min(ts) < ? AND count(*) > 1
+            """
+
+            txn.execute(select_sql, (yesterday,))
+            rows = txn.fetchall()
+
+            if not rows:
+                return
+
+            logger.info(
+                "Pruning old outbound device list updates for %i users/destinations: %s",
+                len(rows),
+                shortstr((row[0], row[1]) for row in rows),
+            )
+
+            # we want to keep the update with the highest stream_id for each user.
+            #
+            # there might be more than one update (with different device_ids) with the
+            # same stream_id, so we also delete all but one rows with the max stream id.
+            delete_sql = """
+                DELETE FROM device_lists_outbound_pokes
+                WHERE destination = ? AND user_id = ? AND (
+                    stream_id < ? OR
+                    (stream_id = ? AND device_id != ?)
+                )
+            """
+            count = 0
+            for (destination, user_id, stream_id, device_id) in rows:
+                txn.execute(
+                    delete_sql, (destination, user_id, stream_id, stream_id, device_id)
+                )
+                count += txn.rowcount
+
+            # Since we've deleted unsent deltas, we need to remove the entry
+            # of last successful sent so that the prev_ids are correctly set.
+            sql = """
+                DELETE FROM device_lists_outbound_last_success
+                WHERE destination = ? AND user_id = ?
+            """
+            txn.executemany(sql, ((row[0], row[1]) for row in rows))
+
+            logger.info("Pruned %d device list outbound pokes", count)
+
+        return run_as_background_process(
+            "prune_old_outbound_device_pokes",
+            self.db_pool.runInteraction,
+            "_prune_old_outbound_device_pokes",
+            _prune_txn,
+        )
diff --git a/synapse/storage/databases/main/directory.py b/synapse/storage/databases/main/directory.py
new file mode 100644
index 0000000000..7819bfcbb3
--- /dev/null
+++ b/synapse/storage/databases/main/directory.py
@@ -0,0 +1,195 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from collections import namedtuple
+from typing import Optional
+
+from twisted.internet import defer
+
+from synapse.api.errors import SynapseError
+from synapse.storage._base import SQLBaseStore
+from synapse.util.caches.descriptors import cached
+
+RoomAliasMapping = namedtuple("RoomAliasMapping", ("room_id", "room_alias", "servers"))
+
+
+class DirectoryWorkerStore(SQLBaseStore):
+    @defer.inlineCallbacks
+    def get_association_from_room_alias(self, room_alias):
+        """ Get's the room_id and server list for a given room_alias
+
+        Args:
+            room_alias (RoomAlias)
+
+        Returns:
+            Deferred: results in namedtuple with keys "room_id" and
+            "servers" or None if no association can be found
+        """
+        room_id = yield self.db_pool.simple_select_one_onecol(
+            "room_aliases",
+            {"room_alias": room_alias.to_string()},
+            "room_id",
+            allow_none=True,
+            desc="get_association_from_room_alias",
+        )
+
+        if not room_id:
+            return None
+
+        servers = yield self.db_pool.simple_select_onecol(
+            "room_alias_servers",
+            {"room_alias": room_alias.to_string()},
+            "server",
+            desc="get_association_from_room_alias",
+        )
+
+        if not servers:
+            return None
+
+        return RoomAliasMapping(room_id, room_alias.to_string(), servers)
+
+    def get_room_alias_creator(self, room_alias):
+        return self.db_pool.simple_select_one_onecol(
+            table="room_aliases",
+            keyvalues={"room_alias": room_alias},
+            retcol="creator",
+            desc="get_room_alias_creator",
+        )
+
+    @cached(max_entries=5000)
+    def get_aliases_for_room(self, room_id):
+        return self.db_pool.simple_select_onecol(
+            "room_aliases",
+            {"room_id": room_id},
+            "room_alias",
+            desc="get_aliases_for_room",
+        )
+
+
+class DirectoryStore(DirectoryWorkerStore):
+    @defer.inlineCallbacks
+    def create_room_alias_association(self, room_alias, room_id, servers, creator=None):
+        """ Creates an association between a room alias and room_id/servers
+
+        Args:
+            room_alias (RoomAlias)
+            room_id (str)
+            servers (list)
+            creator (str): Optional user_id of creator.
+
+        Returns:
+            Deferred
+        """
+
+        def alias_txn(txn):
+            self.db_pool.simple_insert_txn(
+                txn,
+                "room_aliases",
+                {
+                    "room_alias": room_alias.to_string(),
+                    "room_id": room_id,
+                    "creator": creator,
+                },
+            )
+
+            self.db_pool.simple_insert_many_txn(
+                txn,
+                table="room_alias_servers",
+                values=[
+                    {"room_alias": room_alias.to_string(), "server": server}
+                    for server in servers
+                ],
+            )
+
+            self._invalidate_cache_and_stream(
+                txn, self.get_aliases_for_room, (room_id,)
+            )
+
+        try:
+            ret = yield self.db_pool.runInteraction(
+                "create_room_alias_association", alias_txn
+            )
+        except self.database_engine.module.IntegrityError:
+            raise SynapseError(
+                409, "Room alias %s already exists" % room_alias.to_string()
+            )
+        return ret
+
+    @defer.inlineCallbacks
+    def delete_room_alias(self, room_alias):
+        room_id = yield self.db_pool.runInteraction(
+            "delete_room_alias", self._delete_room_alias_txn, room_alias
+        )
+
+        return room_id
+
+    def _delete_room_alias_txn(self, txn, room_alias):
+        txn.execute(
+            "SELECT room_id FROM room_aliases WHERE room_alias = ?",
+            (room_alias.to_string(),),
+        )
+
+        res = txn.fetchone()
+        if res:
+            room_id = res[0]
+        else:
+            return None
+
+        txn.execute(
+            "DELETE FROM room_aliases WHERE room_alias = ?", (room_alias.to_string(),)
+        )
+
+        txn.execute(
+            "DELETE FROM room_alias_servers WHERE room_alias = ?",
+            (room_alias.to_string(),),
+        )
+
+        self._invalidate_cache_and_stream(txn, self.get_aliases_for_room, (room_id,))
+
+        return room_id
+
+    def update_aliases_for_room(
+        self, old_room_id: str, new_room_id: str, creator: Optional[str] = None,
+    ):
+        """Repoint all of the aliases for a given room, to a different room.
+
+        Args:
+            old_room_id:
+            new_room_id:
+            creator: The user to record as the creator of the new mapping.
+                If None, the creator will be left unchanged.
+        """
+
+        def _update_aliases_for_room_txn(txn):
+            update_creator_sql = ""
+            sql_params = (new_room_id, old_room_id)
+            if creator:
+                update_creator_sql = ", creator = ?"
+                sql_params = (new_room_id, creator, old_room_id)
+
+            sql = "UPDATE room_aliases SET room_id = ? %s WHERE room_id = ?" % (
+                update_creator_sql,
+            )
+            txn.execute(sql, sql_params)
+            self._invalidate_cache_and_stream(
+                txn, self.get_aliases_for_room, (old_room_id,)
+            )
+            self._invalidate_cache_and_stream(
+                txn, self.get_aliases_for_room, (new_room_id,)
+            )
+
+        return self.db_pool.runInteraction(
+            "_update_aliases_for_room_txn", _update_aliases_for_room_txn
+        )
diff --git a/synapse/storage/databases/main/e2e_room_keys.py b/synapse/storage/databases/main/e2e_room_keys.py
new file mode 100644
index 0000000000..90152edc3c
--- /dev/null
+++ b/synapse/storage/databases/main/e2e_room_keys.py
@@ -0,0 +1,439 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 New Vector Ltd
+# Copyright 2019 Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.api.errors import StoreError
+from synapse.logging.opentracing import log_kv, trace
+from synapse.storage._base import SQLBaseStore, db_to_json
+
+
+class EndToEndRoomKeyStore(SQLBaseStore):
+    @defer.inlineCallbacks
+    def update_e2e_room_key(self, user_id, version, room_id, session_id, room_key):
+        """Replaces the encrypted E2E room key for a given session in a given backup
+
+        Args:
+            user_id(str): the user whose backup we're setting
+            version(str): the version ID of the backup we're updating
+            room_id(str): the ID of the room whose keys we're setting
+            session_id(str): the session whose room_key we're setting
+            room_key(dict): the room_key being set
+        Raises:
+            StoreError
+        """
+
+        yield self.db_pool.simple_update_one(
+            table="e2e_room_keys",
+            keyvalues={
+                "user_id": user_id,
+                "version": version,
+                "room_id": room_id,
+                "session_id": session_id,
+            },
+            updatevalues={
+                "first_message_index": room_key["first_message_index"],
+                "forwarded_count": room_key["forwarded_count"],
+                "is_verified": room_key["is_verified"],
+                "session_data": json.dumps(room_key["session_data"]),
+            },
+            desc="update_e2e_room_key",
+        )
+
+    @defer.inlineCallbacks
+    def add_e2e_room_keys(self, user_id, version, room_keys):
+        """Bulk add room keys to a given backup.
+
+        Args:
+            user_id (str): the user whose backup we're adding to
+            version (str): the version ID of the backup for the set of keys we're adding to
+            room_keys (iterable[(str, str, dict)]): the keys to add, in the form
+                (roomID, sessionID, keyData)
+        """
+
+        values = []
+        for (room_id, session_id, room_key) in room_keys:
+            values.append(
+                {
+                    "user_id": user_id,
+                    "version": version,
+                    "room_id": room_id,
+                    "session_id": session_id,
+                    "first_message_index": room_key["first_message_index"],
+                    "forwarded_count": room_key["forwarded_count"],
+                    "is_verified": room_key["is_verified"],
+                    "session_data": json.dumps(room_key["session_data"]),
+                }
+            )
+            log_kv(
+                {
+                    "message": "Set room key",
+                    "room_id": room_id,
+                    "session_id": session_id,
+                    "room_key": room_key,
+                }
+            )
+
+        yield self.db_pool.simple_insert_many(
+            table="e2e_room_keys", values=values, desc="add_e2e_room_keys"
+        )
+
+    @trace
+    @defer.inlineCallbacks
+    def get_e2e_room_keys(self, user_id, version, room_id=None, session_id=None):
+        """Bulk get the E2E room keys for a given backup, optionally filtered to a given
+        room, or a given session.
+
+        Args:
+            user_id (str): the user whose backup we're querying
+            version (str): the version ID of the backup for the set of keys we're querying
+            room_id (str): Optional. the ID of the room whose keys we're querying, if any.
+                If not specified, we return the keys for all the rooms in the backup.
+            session_id (str): Optional. the session whose room_key we're querying, if any.
+                If specified, we also require the room_id to be specified.
+                If not specified, we return all the keys in this version of
+                the backup (or for the specified room)
+
+        Returns:
+            A deferred list of dicts giving the session_data and message metadata for
+            these room keys.
+        """
+
+        try:
+            version = int(version)
+        except ValueError:
+            return {"rooms": {}}
+
+        keyvalues = {"user_id": user_id, "version": version}
+        if room_id:
+            keyvalues["room_id"] = room_id
+            if session_id:
+                keyvalues["session_id"] = session_id
+
+        rows = yield self.db_pool.simple_select_list(
+            table="e2e_room_keys",
+            keyvalues=keyvalues,
+            retcols=(
+                "user_id",
+                "room_id",
+                "session_id",
+                "first_message_index",
+                "forwarded_count",
+                "is_verified",
+                "session_data",
+            ),
+            desc="get_e2e_room_keys",
+        )
+
+        sessions = {"rooms": {}}
+        for row in rows:
+            room_entry = sessions["rooms"].setdefault(row["room_id"], {"sessions": {}})
+            room_entry["sessions"][row["session_id"]] = {
+                "first_message_index": row["first_message_index"],
+                "forwarded_count": row["forwarded_count"],
+                # is_verified must be returned to the client as a boolean
+                "is_verified": bool(row["is_verified"]),
+                "session_data": db_to_json(row["session_data"]),
+            }
+
+        return sessions
+
+    def get_e2e_room_keys_multi(self, user_id, version, room_keys):
+        """Get multiple room keys at a time.  The difference between this function and
+        get_e2e_room_keys is that this function can be used to retrieve
+        multiple specific keys at a time, whereas get_e2e_room_keys is used for
+        getting all the keys in a backup version, all the keys for a room, or a
+        specific key.
+
+        Args:
+            user_id (str): the user whose backup we're querying
+            version (str): the version ID of the backup we're querying about
+            room_keys (dict[str, dict[str, iterable[str]]]): a map from
+                room ID -> {"session": [session ids]} indicating the session IDs
+                that we want to query
+
+        Returns:
+           Deferred[dict[str, dict[str, dict]]]: a map of room IDs to session IDs to room key
+        """
+
+        return self.db_pool.runInteraction(
+            "get_e2e_room_keys_multi",
+            self._get_e2e_room_keys_multi_txn,
+            user_id,
+            version,
+            room_keys,
+        )
+
+    @staticmethod
+    def _get_e2e_room_keys_multi_txn(txn, user_id, version, room_keys):
+        if not room_keys:
+            return {}
+
+        where_clauses = []
+        params = [user_id, version]
+        for room_id, room in room_keys.items():
+            sessions = list(room["sessions"])
+            if not sessions:
+                continue
+            params.append(room_id)
+            params.extend(sessions)
+            where_clauses.append(
+                "(room_id = ? AND session_id IN (%s))"
+                % (",".join(["?" for _ in sessions]),)
+            )
+
+        # check if we're actually querying something
+        if not where_clauses:
+            return {}
+
+        sql = """
+        SELECT room_id, session_id, first_message_index, forwarded_count,
+               is_verified, session_data
+        FROM e2e_room_keys
+        WHERE user_id = ? AND version = ? AND (%s)
+        """ % (
+            " OR ".join(where_clauses)
+        )
+
+        txn.execute(sql, params)
+
+        ret = {}
+
+        for row in txn:
+            room_id = row[0]
+            session_id = row[1]
+            ret.setdefault(room_id, {})
+            ret[room_id][session_id] = {
+                "first_message_index": row[2],
+                "forwarded_count": row[3],
+                "is_verified": row[4],
+                "session_data": db_to_json(row[5]),
+            }
+
+        return ret
+
+    def count_e2e_room_keys(self, user_id, version):
+        """Get the number of keys in a backup version.
+
+        Args:
+            user_id (str): the user whose backup we're querying
+            version (str): the version ID of the backup we're querying about
+        """
+
+        return self.db_pool.simple_select_one_onecol(
+            table="e2e_room_keys",
+            keyvalues={"user_id": user_id, "version": version},
+            retcol="COUNT(*)",
+            desc="count_e2e_room_keys",
+        )
+
+    @trace
+    @defer.inlineCallbacks
+    def delete_e2e_room_keys(self, user_id, version, room_id=None, session_id=None):
+        """Bulk delete the E2E room keys for a given backup, optionally filtered to a given
+        room or a given session.
+
+        Args:
+            user_id(str): the user whose backup we're deleting from
+            version(str): the version ID of the backup for the set of keys we're deleting
+            room_id(str): Optional. the ID of the room whose keys we're deleting, if any.
+                If not specified, we delete the keys for all the rooms in the backup.
+            session_id(str): Optional. the session whose room_key we're querying, if any.
+                If specified, we also require the room_id to be specified.
+                If not specified, we delete all the keys in this version of
+                the backup (or for the specified room)
+
+        Returns:
+            A deferred of the deletion transaction
+        """
+
+        keyvalues = {"user_id": user_id, "version": int(version)}
+        if room_id:
+            keyvalues["room_id"] = room_id
+            if session_id:
+                keyvalues["session_id"] = session_id
+
+        yield self.db_pool.simple_delete(
+            table="e2e_room_keys", keyvalues=keyvalues, desc="delete_e2e_room_keys"
+        )
+
+    @staticmethod
+    def _get_current_version(txn, user_id):
+        txn.execute(
+            "SELECT MAX(version) FROM e2e_room_keys_versions "
+            "WHERE user_id=? AND deleted=0",
+            (user_id,),
+        )
+        row = txn.fetchone()
+        if not row:
+            raise StoreError(404, "No current backup version")
+        return row[0]
+
+    def get_e2e_room_keys_version_info(self, user_id, version=None):
+        """Get info metadata about a version of our room_keys backup.
+
+        Args:
+            user_id(str): the user whose backup we're querying
+            version(str): Optional. the version ID of the backup we're querying about
+                If missing, we return the information about the current version.
+        Raises:
+            StoreError: with code 404 if there are no e2e_room_keys_versions present
+        Returns:
+            A deferred dict giving the info metadata for this backup version, with
+            fields including:
+                version(str)
+                algorithm(str)
+                auth_data(object): opaque dict supplied by the client
+                etag(int): tag of the keys in the backup
+        """
+
+        def _get_e2e_room_keys_version_info_txn(txn):
+            if version is None:
+                this_version = self._get_current_version(txn, user_id)
+            else:
+                try:
+                    this_version = int(version)
+                except ValueError:
+                    # Our versions are all ints so if we can't convert it to an integer,
+                    # it isn't there.
+                    raise StoreError(404, "No row found")
+
+            result = self.db_pool.simple_select_one_txn(
+                txn,
+                table="e2e_room_keys_versions",
+                keyvalues={"user_id": user_id, "version": this_version, "deleted": 0},
+                retcols=("version", "algorithm", "auth_data", "etag"),
+            )
+            result["auth_data"] = db_to_json(result["auth_data"])
+            result["version"] = str(result["version"])
+            if result["etag"] is None:
+                result["etag"] = 0
+            return result
+
+        return self.db_pool.runInteraction(
+            "get_e2e_room_keys_version_info", _get_e2e_room_keys_version_info_txn
+        )
+
+    @trace
+    def create_e2e_room_keys_version(self, user_id, info):
+        """Atomically creates a new version of this user's e2e_room_keys store
+        with the given version info.
+
+        Args:
+            user_id(str): the user whose backup we're creating a version
+            info(dict): the info about the backup version to be created
+
+        Returns:
+            A deferred string for the newly created version ID
+        """
+
+        def _create_e2e_room_keys_version_txn(txn):
+            txn.execute(
+                "SELECT MAX(version) FROM e2e_room_keys_versions WHERE user_id=?",
+                (user_id,),
+            )
+            current_version = txn.fetchone()[0]
+            if current_version is None:
+                current_version = "0"
+
+            new_version = str(int(current_version) + 1)
+
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="e2e_room_keys_versions",
+                values={
+                    "user_id": user_id,
+                    "version": new_version,
+                    "algorithm": info["algorithm"],
+                    "auth_data": json.dumps(info["auth_data"]),
+                },
+            )
+
+            return new_version
+
+        return self.db_pool.runInteraction(
+            "create_e2e_room_keys_version_txn", _create_e2e_room_keys_version_txn
+        )
+
+    @trace
+    def update_e2e_room_keys_version(
+        self, user_id, version, info=None, version_etag=None
+    ):
+        """Update a given backup version
+
+        Args:
+            user_id(str): the user whose backup version we're updating
+            version(str): the version ID of the backup version we're updating
+            info (dict): the new backup version info to store.  If None, then
+                the backup version info is not updated
+            version_etag (Optional[int]): etag of the keys in the backup.  If
+                None, then the etag is not updated
+        """
+        updatevalues = {}
+
+        if info is not None and "auth_data" in info:
+            updatevalues["auth_data"] = json.dumps(info["auth_data"])
+        if version_etag is not None:
+            updatevalues["etag"] = version_etag
+
+        if updatevalues:
+            return self.db_pool.simple_update(
+                table="e2e_room_keys_versions",
+                keyvalues={"user_id": user_id, "version": version},
+                updatevalues=updatevalues,
+                desc="update_e2e_room_keys_version",
+            )
+
+    @trace
+    def delete_e2e_room_keys_version(self, user_id, version=None):
+        """Delete a given backup version of the user's room keys.
+        Doesn't delete their actual key data.
+
+        Args:
+            user_id(str): the user whose backup version we're deleting
+            version(str): Optional. the version ID of the backup version we're deleting
+                If missing, we delete the current backup version info.
+        Raises:
+            StoreError: with code 404 if there are no e2e_room_keys_versions present,
+                or if the version requested doesn't exist.
+        """
+
+        def _delete_e2e_room_keys_version_txn(txn):
+            if version is None:
+                this_version = self._get_current_version(txn, user_id)
+                if this_version is None:
+                    raise StoreError(404, "No current backup version")
+            else:
+                this_version = version
+
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="e2e_room_keys",
+                keyvalues={"user_id": user_id, "version": this_version},
+            )
+
+            return self.db_pool.simple_update_one_txn(
+                txn,
+                table="e2e_room_keys_versions",
+                keyvalues={"user_id": user_id, "version": this_version},
+                updatevalues={"deleted": 1},
+            )
+
+        return self.db_pool.runInteraction(
+            "delete_e2e_room_keys_version", _delete_e2e_room_keys_version_txn
+        )
diff --git a/synapse/storage/databases/main/end_to_end_keys.py b/synapse/storage/databases/main/end_to_end_keys.py
new file mode 100644
index 0000000000..40354b8304
--- /dev/null
+++ b/synapse/storage/databases/main/end_to_end_keys.py
@@ -0,0 +1,748 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015, 2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from typing import Dict, List, Tuple
+
+from canonicaljson import encode_canonical_json, json
+
+from twisted.enterprise.adbapi import Connection
+from twisted.internet import defer
+
+from synapse.logging.opentracing import log_kv, set_tag, trace
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.storage.database import make_in_list_sql_clause
+from synapse.util.caches.descriptors import cached, cachedList
+from synapse.util.iterutils import batch_iter
+
+
+class EndToEndKeyWorkerStore(SQLBaseStore):
+    @trace
+    @defer.inlineCallbacks
+    def get_e2e_device_keys(
+        self, query_list, include_all_devices=False, include_deleted_devices=False
+    ):
+        """Fetch a list of device keys.
+        Args:
+            query_list(list): List of pairs of user_ids and device_ids.
+            include_all_devices (bool): whether to include entries for devices
+                that don't have device keys
+            include_deleted_devices (bool): whether to include null entries for
+                devices which no longer exist (but were in the query_list).
+                This option only takes effect if include_all_devices is true.
+        Returns:
+            Dict mapping from user-id to dict mapping from device_id to
+            key data.  The key data will be a dict in the same format as the
+            DeviceKeys type returned by POST /_matrix/client/r0/keys/query.
+        """
+        set_tag("query_list", query_list)
+        if not query_list:
+            return {}
+
+        results = yield self.db_pool.runInteraction(
+            "get_e2e_device_keys",
+            self._get_e2e_device_keys_txn,
+            query_list,
+            include_all_devices,
+            include_deleted_devices,
+        )
+
+        # Build the result structure, un-jsonify the results, and add the
+        # "unsigned" section
+        rv = {}
+        for user_id, device_keys in results.items():
+            rv[user_id] = {}
+            for device_id, device_info in device_keys.items():
+                r = db_to_json(device_info.pop("key_json"))
+                r["unsigned"] = {}
+                display_name = device_info["device_display_name"]
+                if display_name is not None:
+                    r["unsigned"]["device_display_name"] = display_name
+                if "signatures" in device_info:
+                    for sig_user_id, sigs in device_info["signatures"].items():
+                        r.setdefault("signatures", {}).setdefault(
+                            sig_user_id, {}
+                        ).update(sigs)
+                rv[user_id][device_id] = r
+
+        return rv
+
+    @trace
+    def _get_e2e_device_keys_txn(
+        self, txn, query_list, include_all_devices=False, include_deleted_devices=False
+    ):
+        set_tag("include_all_devices", include_all_devices)
+        set_tag("include_deleted_devices", include_deleted_devices)
+
+        query_clauses = []
+        query_params = []
+        signature_query_clauses = []
+        signature_query_params = []
+
+        if include_all_devices is False:
+            include_deleted_devices = False
+
+        if include_deleted_devices:
+            deleted_devices = set(query_list)
+
+        for (user_id, device_id) in query_list:
+            query_clause = "user_id = ?"
+            query_params.append(user_id)
+            signature_query_clause = "target_user_id = ?"
+            signature_query_params.append(user_id)
+
+            if device_id is not None:
+                query_clause += " AND device_id = ?"
+                query_params.append(device_id)
+                signature_query_clause += " AND target_device_id = ?"
+                signature_query_params.append(device_id)
+
+            signature_query_clause += " AND user_id = ?"
+            signature_query_params.append(user_id)
+
+            query_clauses.append(query_clause)
+            signature_query_clauses.append(signature_query_clause)
+
+        sql = (
+            "SELECT user_id, device_id, "
+            "    d.display_name AS device_display_name, "
+            "    k.key_json"
+            " FROM devices d"
+            "    %s JOIN e2e_device_keys_json k USING (user_id, device_id)"
+            " WHERE %s AND NOT d.hidden"
+        ) % (
+            "LEFT" if include_all_devices else "INNER",
+            " OR ".join("(" + q + ")" for q in query_clauses),
+        )
+
+        txn.execute(sql, query_params)
+        rows = self.db_pool.cursor_to_dict(txn)
+
+        result = {}
+        for row in rows:
+            if include_deleted_devices:
+                deleted_devices.remove((row["user_id"], row["device_id"]))
+            result.setdefault(row["user_id"], {})[row["device_id"]] = row
+
+        if include_deleted_devices:
+            for user_id, device_id in deleted_devices:
+                result.setdefault(user_id, {})[device_id] = None
+
+        # get signatures on the device
+        signature_sql = ("SELECT *  FROM e2e_cross_signing_signatures WHERE %s") % (
+            " OR ".join("(" + q + ")" for q in signature_query_clauses)
+        )
+
+        txn.execute(signature_sql, signature_query_params)
+        rows = self.db_pool.cursor_to_dict(txn)
+
+        # add each cross-signing signature to the correct device in the result dict.
+        for row in rows:
+            signing_user_id = row["user_id"]
+            signing_key_id = row["key_id"]
+            target_user_id = row["target_user_id"]
+            target_device_id = row["target_device_id"]
+            signature = row["signature"]
+
+            target_user_result = result.get(target_user_id)
+            if not target_user_result:
+                continue
+
+            target_device_result = target_user_result.get(target_device_id)
+            if not target_device_result:
+                # note that target_device_result will be None for deleted devices.
+                continue
+
+            target_device_signatures = target_device_result.setdefault("signatures", {})
+            signing_user_signatures = target_device_signatures.setdefault(
+                signing_user_id, {}
+            )
+            signing_user_signatures[signing_key_id] = signature
+
+        log_kv(result)
+        return result
+
+    @defer.inlineCallbacks
+    def get_e2e_one_time_keys(self, user_id, device_id, key_ids):
+        """Retrieve a number of one-time keys for a user
+
+        Args:
+            user_id(str): id of user to get keys for
+            device_id(str): id of device to get keys for
+            key_ids(list[str]): list of key ids (excluding algorithm) to
+                retrieve
+
+        Returns:
+            deferred resolving to Dict[(str, str), str]: map from (algorithm,
+            key_id) to json string for key
+        """
+
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="e2e_one_time_keys_json",
+            column="key_id",
+            iterable=key_ids,
+            retcols=("algorithm", "key_id", "key_json"),
+            keyvalues={"user_id": user_id, "device_id": device_id},
+            desc="add_e2e_one_time_keys_check",
+        )
+        result = {(row["algorithm"], row["key_id"]): row["key_json"] for row in rows}
+        log_kv({"message": "Fetched one time keys for user", "one_time_keys": result})
+        return result
+
+    @defer.inlineCallbacks
+    def add_e2e_one_time_keys(self, user_id, device_id, time_now, new_keys):
+        """Insert some new one time keys for a device. Errors if any of the
+        keys already exist.
+
+        Args:
+            user_id(str): id of user to get keys for
+            device_id(str): id of device to get keys for
+            time_now(long): insertion time to record (ms since epoch)
+            new_keys(iterable[(str, str, str)]: keys to add - each a tuple of
+                (algorithm, key_id, key json)
+        """
+
+        def _add_e2e_one_time_keys(txn):
+            set_tag("user_id", user_id)
+            set_tag("device_id", device_id)
+            set_tag("new_keys", new_keys)
+            # We are protected from race between lookup and insertion due to
+            # a unique constraint. If there is a race of two calls to
+            # `add_e2e_one_time_keys` then they'll conflict and we will only
+            # insert one set.
+            self.db_pool.simple_insert_many_txn(
+                txn,
+                table="e2e_one_time_keys_json",
+                values=[
+                    {
+                        "user_id": user_id,
+                        "device_id": device_id,
+                        "algorithm": algorithm,
+                        "key_id": key_id,
+                        "ts_added_ms": time_now,
+                        "key_json": json_bytes,
+                    }
+                    for algorithm, key_id, json_bytes in new_keys
+                ],
+            )
+            self._invalidate_cache_and_stream(
+                txn, self.count_e2e_one_time_keys, (user_id, device_id)
+            )
+
+        yield self.db_pool.runInteraction(
+            "add_e2e_one_time_keys_insert", _add_e2e_one_time_keys
+        )
+
+    @cached(max_entries=10000)
+    def count_e2e_one_time_keys(self, user_id, device_id):
+        """ Count the number of one time keys the server has for a device
+        Returns:
+            Dict mapping from algorithm to number of keys for that algorithm.
+        """
+
+        def _count_e2e_one_time_keys(txn):
+            sql = (
+                "SELECT algorithm, COUNT(key_id) FROM e2e_one_time_keys_json"
+                " WHERE user_id = ? AND device_id = ?"
+                " GROUP BY algorithm"
+            )
+            txn.execute(sql, (user_id, device_id))
+            result = {}
+            for algorithm, key_count in txn:
+                result[algorithm] = key_count
+            return result
+
+        return self.db_pool.runInteraction(
+            "count_e2e_one_time_keys", _count_e2e_one_time_keys
+        )
+
+    @defer.inlineCallbacks
+    def get_e2e_cross_signing_key(self, user_id, key_type, from_user_id=None):
+        """Returns a user's cross-signing key.
+
+        Args:
+            user_id (str): the user whose key is being requested
+            key_type (str): the type of key that is being requested: either 'master'
+                for a master key, 'self_signing' for a self-signing key, or
+                'user_signing' for a user-signing key
+            from_user_id (str): if specified, signatures made by this user on
+                the self-signing key will be included in the result
+
+        Returns:
+            dict of the key data or None if not found
+        """
+        res = yield self.get_e2e_cross_signing_keys_bulk([user_id], from_user_id)
+        user_keys = res.get(user_id)
+        if not user_keys:
+            return None
+        return user_keys.get(key_type)
+
+    @cached(num_args=1)
+    def _get_bare_e2e_cross_signing_keys(self, user_id):
+        """Dummy function.  Only used to make a cache for
+        _get_bare_e2e_cross_signing_keys_bulk.
+        """
+        raise NotImplementedError()
+
+    @cachedList(
+        cached_method_name="_get_bare_e2e_cross_signing_keys",
+        list_name="user_ids",
+        num_args=1,
+    )
+    def _get_bare_e2e_cross_signing_keys_bulk(
+        self, user_ids: List[str]
+    ) -> Dict[str, Dict[str, dict]]:
+        """Returns the cross-signing keys for a set of users.  The output of this
+        function should be passed to _get_e2e_cross_signing_signatures_txn if
+        the signatures for the calling user need to be fetched.
+
+        Args:
+            user_ids (list[str]): the users whose keys are being requested
+
+        Returns:
+            dict[str, dict[str, dict]]: mapping from user ID to key type to key
+                data.  If a user's cross-signing keys were not found, either
+                their user ID will not be in the dict, or their user ID will map
+                to None.
+
+        """
+        return self.db_pool.runInteraction(
+            "get_bare_e2e_cross_signing_keys_bulk",
+            self._get_bare_e2e_cross_signing_keys_bulk_txn,
+            user_ids,
+        )
+
+    def _get_bare_e2e_cross_signing_keys_bulk_txn(
+        self, txn: Connection, user_ids: List[str],
+    ) -> Dict[str, Dict[str, dict]]:
+        """Returns the cross-signing keys for a set of users.  The output of this
+        function should be passed to _get_e2e_cross_signing_signatures_txn if
+        the signatures for the calling user need to be fetched.
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            user_ids (list[str]): the users whose keys are being requested
+
+        Returns:
+            dict[str, dict[str, dict]]: mapping from user ID to key type to key
+                data.  If a user's cross-signing keys were not found, their user
+                ID will not be in the dict.
+
+        """
+        result = {}
+
+        for user_chunk in batch_iter(user_ids, 100):
+            clause, params = make_in_list_sql_clause(
+                txn.database_engine, "k.user_id", user_chunk
+            )
+            sql = (
+                """
+                SELECT k.user_id, k.keytype, k.keydata, k.stream_id
+                  FROM e2e_cross_signing_keys k
+                  INNER JOIN (SELECT user_id, keytype, MAX(stream_id) AS stream_id
+                                FROM e2e_cross_signing_keys
+                               GROUP BY user_id, keytype) s
+                 USING (user_id, stream_id, keytype)
+                 WHERE
+            """
+                + clause
+            )
+
+            txn.execute(sql, params)
+            rows = self.db_pool.cursor_to_dict(txn)
+
+            for row in rows:
+                user_id = row["user_id"]
+                key_type = row["keytype"]
+                key = db_to_json(row["keydata"])
+                user_info = result.setdefault(user_id, {})
+                user_info[key_type] = key
+
+        return result
+
+    def _get_e2e_cross_signing_signatures_txn(
+        self, txn: Connection, keys: Dict[str, Dict[str, dict]], from_user_id: str,
+    ) -> Dict[str, Dict[str, dict]]:
+        """Returns the cross-signing signatures made by a user on a set of keys.
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            keys (dict[str, dict[str, dict]]): a map of user ID to key type to
+                key data.  This dict will be modified to add signatures.
+            from_user_id (str): fetch the signatures made by this user
+
+        Returns:
+            dict[str, dict[str, dict]]: mapping from user ID to key type to key
+                data.  The return value will be the same as the keys argument,
+                with the modifications included.
+        """
+
+        # find out what cross-signing keys (a.k.a. devices) we need to get
+        # signatures for.  This is a map of (user_id, device_id) to key type
+        # (device_id is the key's public part).
+        devices = {}
+
+        for user_id, user_info in keys.items():
+            if user_info is None:
+                continue
+            for key_type, key in user_info.items():
+                device_id = None
+                for k in key["keys"].values():
+                    device_id = k
+                devices[(user_id, device_id)] = key_type
+
+        for batch in batch_iter(devices.keys(), size=100):
+            sql = """
+                SELECT target_user_id, target_device_id, key_id, signature
+                  FROM e2e_cross_signing_signatures
+                 WHERE user_id = ?
+                   AND (%s)
+            """ % (
+                " OR ".join(
+                    "(target_user_id = ? AND target_device_id = ?)" for _ in batch
+                )
+            )
+            query_params = [from_user_id]
+            for item in batch:
+                # item is a (user_id, device_id) tuple
+                query_params.extend(item)
+
+            txn.execute(sql, query_params)
+            rows = self.db_pool.cursor_to_dict(txn)
+
+            # and add the signatures to the appropriate keys
+            for row in rows:
+                key_id = row["key_id"]
+                target_user_id = row["target_user_id"]
+                target_device_id = row["target_device_id"]
+                key_type = devices[(target_user_id, target_device_id)]
+                # We need to copy everything, because the result may have come
+                # from the cache.  dict.copy only does a shallow copy, so we
+                # need to recursively copy the dicts that will be modified.
+                user_info = keys[target_user_id] = keys[target_user_id].copy()
+                target_user_key = user_info[key_type] = user_info[key_type].copy()
+                if "signatures" in target_user_key:
+                    signatures = target_user_key["signatures"] = target_user_key[
+                        "signatures"
+                    ].copy()
+                    if from_user_id in signatures:
+                        user_sigs = signatures[from_user_id] = signatures[from_user_id]
+                        user_sigs[key_id] = row["signature"]
+                    else:
+                        signatures[from_user_id] = {key_id: row["signature"]}
+                else:
+                    target_user_key["signatures"] = {
+                        from_user_id: {key_id: row["signature"]}
+                    }
+
+        return keys
+
+    @defer.inlineCallbacks
+    def get_e2e_cross_signing_keys_bulk(
+        self, user_ids: List[str], from_user_id: str = None
+    ) -> defer.Deferred:
+        """Returns the cross-signing keys for a set of users.
+
+        Args:
+            user_ids (list[str]): the users whose keys are being requested
+            from_user_id (str): if specified, signatures made by this user on
+                the self-signing keys will be included in the result
+
+        Returns:
+            Deferred[dict[str, dict[str, dict]]]: map of user ID to key type to
+                key data.  If a user's cross-signing keys were not found, either
+                their user ID will not be in the dict, or their user ID will map
+                to None.
+        """
+
+        result = yield self._get_bare_e2e_cross_signing_keys_bulk(user_ids)
+
+        if from_user_id:
+            result = yield self.db_pool.runInteraction(
+                "get_e2e_cross_signing_signatures",
+                self._get_e2e_cross_signing_signatures_txn,
+                result,
+                from_user_id,
+            )
+
+        return result
+
+    async def get_all_user_signature_changes_for_remotes(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for groups replication stream.
+
+        Note that the user signature stream represents when a user signs their
+        device with their user-signing key, which is not published to other
+        users or servers, so no `destination` is needed in the returned
+        list. However, this is needed to poke workers.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def _get_all_user_signature_changes_for_remotes_txn(txn):
+            sql = """
+                SELECT stream_id, from_user_id AS user_id
+                FROM user_signature_stream
+                WHERE ? < stream_id AND stream_id <= ?
+                ORDER BY stream_id ASC
+                LIMIT ?
+            """
+            txn.execute(sql, (last_id, current_id, limit))
+
+            updates = [(row[0], (row[1:])) for row in txn]
+
+            limited = False
+            upto_token = current_id
+            if len(updates) >= limit:
+                upto_token = updates[-1][0]
+                limited = True
+
+            return updates, upto_token, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_user_signature_changes_for_remotes",
+            _get_all_user_signature_changes_for_remotes_txn,
+        )
+
+
+class EndToEndKeyStore(EndToEndKeyWorkerStore, SQLBaseStore):
+    def set_e2e_device_keys(self, user_id, device_id, time_now, device_keys):
+        """Stores device keys for a device. Returns whether there was a change
+        or the keys were already in the database.
+        """
+
+        def _set_e2e_device_keys_txn(txn):
+            set_tag("user_id", user_id)
+            set_tag("device_id", device_id)
+            set_tag("time_now", time_now)
+            set_tag("device_keys", device_keys)
+
+            old_key_json = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="e2e_device_keys_json",
+                keyvalues={"user_id": user_id, "device_id": device_id},
+                retcol="key_json",
+                allow_none=True,
+            )
+
+            # In py3 we need old_key_json to match new_key_json type. The DB
+            # returns unicode while encode_canonical_json returns bytes.
+            new_key_json = encode_canonical_json(device_keys).decode("utf-8")
+
+            if old_key_json == new_key_json:
+                log_kv({"Message": "Device key already stored."})
+                return False
+
+            self.db_pool.simple_upsert_txn(
+                txn,
+                table="e2e_device_keys_json",
+                keyvalues={"user_id": user_id, "device_id": device_id},
+                values={"ts_added_ms": time_now, "key_json": new_key_json},
+            )
+            log_kv({"message": "Device keys stored."})
+            return True
+
+        return self.db_pool.runInteraction(
+            "set_e2e_device_keys", _set_e2e_device_keys_txn
+        )
+
+    def claim_e2e_one_time_keys(self, query_list):
+        """Take a list of one time keys out of the database"""
+
+        @trace
+        def _claim_e2e_one_time_keys(txn):
+            sql = (
+                "SELECT key_id, key_json FROM e2e_one_time_keys_json"
+                " WHERE user_id = ? AND device_id = ? AND algorithm = ?"
+                " LIMIT 1"
+            )
+            result = {}
+            delete = []
+            for user_id, device_id, algorithm in query_list:
+                user_result = result.setdefault(user_id, {})
+                device_result = user_result.setdefault(device_id, {})
+                txn.execute(sql, (user_id, device_id, algorithm))
+                for key_id, key_json in txn:
+                    device_result[algorithm + ":" + key_id] = key_json
+                    delete.append((user_id, device_id, algorithm, key_id))
+            sql = (
+                "DELETE FROM e2e_one_time_keys_json"
+                " WHERE user_id = ? AND device_id = ? AND algorithm = ?"
+                " AND key_id = ?"
+            )
+            for user_id, device_id, algorithm, key_id in delete:
+                log_kv(
+                    {
+                        "message": "Executing claim e2e_one_time_keys transaction on database."
+                    }
+                )
+                txn.execute(sql, (user_id, device_id, algorithm, key_id))
+                log_kv({"message": "finished executing and invalidating cache"})
+                self._invalidate_cache_and_stream(
+                    txn, self.count_e2e_one_time_keys, (user_id, device_id)
+                )
+            return result
+
+        return self.db_pool.runInteraction(
+            "claim_e2e_one_time_keys", _claim_e2e_one_time_keys
+        )
+
+    def delete_e2e_keys_by_device(self, user_id, device_id):
+        def delete_e2e_keys_by_device_txn(txn):
+            log_kv(
+                {
+                    "message": "Deleting keys for device",
+                    "device_id": device_id,
+                    "user_id": user_id,
+                }
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="e2e_device_keys_json",
+                keyvalues={"user_id": user_id, "device_id": device_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="e2e_one_time_keys_json",
+                keyvalues={"user_id": user_id, "device_id": device_id},
+            )
+            self._invalidate_cache_and_stream(
+                txn, self.count_e2e_one_time_keys, (user_id, device_id)
+            )
+
+        return self.db_pool.runInteraction(
+            "delete_e2e_keys_by_device", delete_e2e_keys_by_device_txn
+        )
+
+    def _set_e2e_cross_signing_key_txn(self, txn, user_id, key_type, key):
+        """Set a user's cross-signing key.
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            user_id (str): the user to set the signing key for
+            key_type (str): the type of key that is being set: either 'master'
+                for a master key, 'self_signing' for a self-signing key, or
+                'user_signing' for a user-signing key
+            key (dict): the key data
+        """
+        # the 'key' dict will look something like:
+        # {
+        #   "user_id": "@alice:example.com",
+        #   "usage": ["self_signing"],
+        #   "keys": {
+        #     "ed25519:base64+self+signing+public+key": "base64+self+signing+public+key",
+        #   },
+        #   "signatures": {
+        #     "@alice:example.com": {
+        #       "ed25519:base64+master+public+key": "base64+signature"
+        #     }
+        #   }
+        # }
+        # The "keys" property must only have one entry, which will be the public
+        # key, so we just grab the first value in there
+        pubkey = next(iter(key["keys"].values()))
+
+        # The cross-signing keys need to occupy the same namespace as devices,
+        # since signatures are identified by device ID.  So add an entry to the
+        # device table to make sure that we don't have a collision with device
+        # IDs.
+        # We only need to do this for local users, since remote servers should be
+        # responsible for checking this for their own users.
+        if self.hs.is_mine_id(user_id):
+            self.db_pool.simple_insert_txn(
+                txn,
+                "devices",
+                values={
+                    "user_id": user_id,
+                    "device_id": pubkey,
+                    "display_name": key_type + " signing key",
+                    "hidden": True,
+                },
+            )
+
+        # and finally, store the key itself
+        with self._cross_signing_id_gen.get_next() as stream_id:
+            self.db_pool.simple_insert_txn(
+                txn,
+                "e2e_cross_signing_keys",
+                values={
+                    "user_id": user_id,
+                    "keytype": key_type,
+                    "keydata": json.dumps(key),
+                    "stream_id": stream_id,
+                },
+            )
+
+        self._invalidate_cache_and_stream(
+            txn, self._get_bare_e2e_cross_signing_keys, (user_id,)
+        )
+
+    def set_e2e_cross_signing_key(self, user_id, key_type, key):
+        """Set a user's cross-signing key.
+
+        Args:
+            user_id (str): the user to set the user-signing key for
+            key_type (str): the type of cross-signing key to set
+            key (dict): the key data
+        """
+        return self.db_pool.runInteraction(
+            "add_e2e_cross_signing_key",
+            self._set_e2e_cross_signing_key_txn,
+            user_id,
+            key_type,
+            key,
+        )
+
+    def store_e2e_cross_signing_signatures(self, user_id, signatures):
+        """Stores cross-signing signatures.
+
+        Args:
+            user_id (str): the user who made the signatures
+            signatures (iterable[SignatureListItem]): signatures to add
+        """
+        return self.db_pool.simple_insert_many(
+            "e2e_cross_signing_signatures",
+            [
+                {
+                    "user_id": user_id,
+                    "key_id": item.signing_key_id,
+                    "target_user_id": item.target_user_id,
+                    "target_device_id": item.target_device_id,
+                    "signature": item.signature,
+                }
+                for item in signatures
+            ],
+            "add_e2e_signing_key",
+        )
diff --git a/synapse/storage/databases/main/event_federation.py b/synapse/storage/databases/main/event_federation.py
new file mode 100644
index 0000000000..eddb32b4d3
--- /dev/null
+++ b/synapse/storage/databases/main/event_federation.py
@@ -0,0 +1,726 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import itertools
+import logging
+from queue import Empty, PriorityQueue
+from typing import Dict, List, Optional, Set, Tuple
+
+from twisted.internet import defer
+
+from synapse.api.errors import StoreError
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import SQLBaseStore, make_in_list_sql_clause
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.events_worker import EventsWorkerStore
+from synapse.storage.databases.main.signatures import SignatureWorkerStore
+from synapse.util.caches.descriptors import cached
+from synapse.util.iterutils import batch_iter
+
+logger = logging.getLogger(__name__)
+
+
+class EventFederationWorkerStore(EventsWorkerStore, SignatureWorkerStore, SQLBaseStore):
+    def get_auth_chain(self, event_ids, include_given=False):
+        """Get auth events for given event_ids. The events *must* be state events.
+
+        Args:
+            event_ids (list): state events
+            include_given (bool): include the given events in result
+
+        Returns:
+            list of events
+        """
+        return self.get_auth_chain_ids(
+            event_ids, include_given=include_given
+        ).addCallback(self.get_events_as_list)
+
+    def get_auth_chain_ids(
+        self,
+        event_ids: List[str],
+        include_given: bool = False,
+        ignore_events: Optional[Set[str]] = None,
+    ):
+        """Get auth events for given event_ids. The events *must* be state events.
+
+        Args:
+            event_ids: state events
+            include_given: include the given events in result
+            ignore_events: Set of events to exclude from the returned auth
+                chain. This is useful if the caller will just discard the
+                given events anyway, and saves us from figuring out their auth
+                chains if not required.
+
+        Returns:
+            list of event_ids
+        """
+        return self.db_pool.runInteraction(
+            "get_auth_chain_ids",
+            self._get_auth_chain_ids_txn,
+            event_ids,
+            include_given,
+            ignore_events,
+        )
+
+    def _get_auth_chain_ids_txn(self, txn, event_ids, include_given, ignore_events):
+        if ignore_events is None:
+            ignore_events = set()
+
+        if include_given:
+            results = set(event_ids)
+        else:
+            results = set()
+
+        base_sql = "SELECT auth_id FROM event_auth WHERE "
+
+        front = set(event_ids)
+        while front:
+            new_front = set()
+            for chunk in batch_iter(front, 100):
+                clause, args = make_in_list_sql_clause(
+                    txn.database_engine, "event_id", chunk
+                )
+                txn.execute(base_sql + clause, args)
+                new_front.update(r[0] for r in txn)
+
+            new_front -= ignore_events
+            new_front -= results
+
+            front = new_front
+            results.update(front)
+
+        return list(results)
+
+    def get_auth_chain_difference(self, state_sets: List[Set[str]]):
+        """Given sets of state events figure out the auth chain difference (as
+        per state res v2 algorithm).
+
+        This equivalent to fetching the full auth chain for each set of state
+        and returning the events that don't appear in each and every auth
+        chain.
+
+        Returns:
+            Deferred[Set[str]]
+        """
+
+        return self.db_pool.runInteraction(
+            "get_auth_chain_difference",
+            self._get_auth_chain_difference_txn,
+            state_sets,
+        )
+
+    def _get_auth_chain_difference_txn(
+        self, txn, state_sets: List[Set[str]]
+    ) -> Set[str]:
+
+        # Algorithm Description
+        # ~~~~~~~~~~~~~~~~~~~~~
+        #
+        # The idea here is to basically walk the auth graph of each state set in
+        # tandem, keeping track of which auth events are reachable by each state
+        # set. If we reach an auth event we've already visited (via a different
+        # state set) then we mark that auth event and all ancestors as reachable
+        # by the state set. This requires that we keep track of the auth chains
+        # in memory.
+        #
+        # Doing it in a such a way means that we can stop early if all auth
+        # events we're currently walking are reachable by all state sets.
+        #
+        # *Note*: We can't stop walking an event's auth chain if it is reachable
+        # by all state sets. This is because other auth chains we're walking
+        # might be reachable only via the original auth chain. For example,
+        # given the following auth chain:
+        #
+        #       A -> C -> D -> E
+        #           /         /
+        #       B -´---------´
+        #
+        # and state sets {A} and {B} then walking the auth chains of A and B
+        # would immediately show that C is reachable by both. However, if we
+        # stopped at C then we'd only reach E via the auth chain of B and so E
+        # would errornously get included in the returned difference.
+        #
+        # The other thing that we do is limit the number of auth chains we walk
+        # at once, due to practical limits (i.e. we can only query the database
+        # with a limited set of parameters). We pick the auth chains we walk
+        # each iteration based on their depth, in the hope that events with a
+        # lower depth are likely reachable by those with higher depths.
+        #
+        # We could use any ordering that we believe would give a rough
+        # topological ordering, e.g. origin server timestamp. If the ordering
+        # chosen is not topological then the algorithm still produces the right
+        # result, but perhaps a bit more inefficiently. This is why it is safe
+        # to use "depth" here.
+
+        initial_events = set(state_sets[0]).union(*state_sets[1:])
+
+        # Dict from events in auth chains to which sets *cannot* reach them.
+        # I.e. if the set is empty then all sets can reach the event.
+        event_to_missing_sets = {
+            event_id: {i for i, a in enumerate(state_sets) if event_id not in a}
+            for event_id in initial_events
+        }
+
+        # The sorted list of events whose auth chains we should walk.
+        search = []  # type: List[Tuple[int, str]]
+
+        # We need to get the depth of the initial events for sorting purposes.
+        sql = """
+            SELECT depth, event_id FROM events
+            WHERE %s
+        """
+        # the list can be huge, so let's avoid looking them all up in one massive
+        # query.
+        for batch in batch_iter(initial_events, 1000):
+            clause, args = make_in_list_sql_clause(
+                txn.database_engine, "event_id", batch
+            )
+            txn.execute(sql % (clause,), args)
+
+            # I think building a temporary list with fetchall is more efficient than
+            # just `search.extend(txn)`, but this is unconfirmed
+            search.extend(txn.fetchall())
+
+        # sort by depth
+        search.sort()
+
+        # Map from event to its auth events
+        event_to_auth_events = {}  # type: Dict[str, Set[str]]
+
+        base_sql = """
+            SELECT a.event_id, auth_id, depth
+            FROM event_auth AS a
+            INNER JOIN events AS e ON (e.event_id = a.auth_id)
+            WHERE
+        """
+
+        while search:
+            # Check whether all our current walks are reachable by all state
+            # sets. If so we can bail.
+            if all(not event_to_missing_sets[eid] for _, eid in search):
+                break
+
+            # Fetch the auth events and their depths of the N last events we're
+            # currently walking
+            search, chunk = search[:-100], search[-100:]
+            clause, args = make_in_list_sql_clause(
+                txn.database_engine, "a.event_id", [e_id for _, e_id in chunk]
+            )
+            txn.execute(base_sql + clause, args)
+
+            for event_id, auth_event_id, auth_event_depth in txn:
+                event_to_auth_events.setdefault(event_id, set()).add(auth_event_id)
+
+                sets = event_to_missing_sets.get(auth_event_id)
+                if sets is None:
+                    # First time we're seeing this event, so we add it to the
+                    # queue of things to fetch.
+                    search.append((auth_event_depth, auth_event_id))
+
+                    # Assume that this event is unreachable from any of the
+                    # state sets until proven otherwise
+                    sets = event_to_missing_sets[auth_event_id] = set(
+                        range(len(state_sets))
+                    )
+                else:
+                    # We've previously seen this event, so look up its auth
+                    # events and recursively mark all ancestors as reachable
+                    # by the current event's state set.
+                    a_ids = event_to_auth_events.get(auth_event_id)
+                    while a_ids:
+                        new_aids = set()
+                        for a_id in a_ids:
+                            event_to_missing_sets[a_id].intersection_update(
+                                event_to_missing_sets[event_id]
+                            )
+
+                            b = event_to_auth_events.get(a_id)
+                            if b:
+                                new_aids.update(b)
+
+                        a_ids = new_aids
+
+                # Mark that the auth event is reachable by the approriate sets.
+                sets.intersection_update(event_to_missing_sets[event_id])
+
+            search.sort()
+
+        # Return all events where not all sets can reach them.
+        return {eid for eid, n in event_to_missing_sets.items() if n}
+
+    def get_oldest_events_in_room(self, room_id):
+        return self.db_pool.runInteraction(
+            "get_oldest_events_in_room", self._get_oldest_events_in_room_txn, room_id
+        )
+
+    def get_oldest_events_with_depth_in_room(self, room_id):
+        return self.db_pool.runInteraction(
+            "get_oldest_events_with_depth_in_room",
+            self.get_oldest_events_with_depth_in_room_txn,
+            room_id,
+        )
+
+    def get_oldest_events_with_depth_in_room_txn(self, txn, room_id):
+        sql = (
+            "SELECT b.event_id, MAX(e.depth) FROM events as e"
+            " INNER JOIN event_edges as g"
+            " ON g.event_id = e.event_id"
+            " INNER JOIN event_backward_extremities as b"
+            " ON g.prev_event_id = b.event_id"
+            " WHERE b.room_id = ? AND g.is_state is ?"
+            " GROUP BY b.event_id"
+        )
+
+        txn.execute(sql, (room_id, False))
+
+        return dict(txn)
+
+    @defer.inlineCallbacks
+    def get_max_depth_of(self, event_ids):
+        """Returns the max depth of a set of event IDs
+
+        Args:
+            event_ids (list[str])
+
+        Returns
+            Deferred[int]
+        """
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="events",
+            column="event_id",
+            iterable=event_ids,
+            retcols=("depth",),
+            desc="get_max_depth_of",
+        )
+
+        if not rows:
+            return 0
+        else:
+            return max(row["depth"] for row in rows)
+
+    def _get_oldest_events_in_room_txn(self, txn, room_id):
+        return self.db_pool.simple_select_onecol_txn(
+            txn,
+            table="event_backward_extremities",
+            keyvalues={"room_id": room_id},
+            retcol="event_id",
+        )
+
+    def get_prev_events_for_room(self, room_id: str):
+        """
+        Gets a subset of the current forward extremities in the given room.
+
+        Limits the result to 10 extremities, so that we can avoid creating
+        events which refer to hundreds of prev_events.
+
+        Args:
+            room_id (str): room_id
+
+        Returns:
+            Deferred[List[str]]: the event ids of the forward extremites
+
+        """
+
+        return self.db_pool.runInteraction(
+            "get_prev_events_for_room", self._get_prev_events_for_room_txn, room_id
+        )
+
+    def _get_prev_events_for_room_txn(self, txn, room_id: str):
+        # we just use the 10 newest events. Older events will become
+        # prev_events of future events.
+
+        sql = """
+            SELECT e.event_id FROM event_forward_extremities AS f
+            INNER JOIN events AS e USING (event_id)
+            WHERE f.room_id = ?
+            ORDER BY e.depth DESC
+            LIMIT 10
+        """
+
+        txn.execute(sql, (room_id,))
+
+        return [row[0] for row in txn]
+
+    def get_rooms_with_many_extremities(self, min_count, limit, room_id_filter):
+        """Get the top rooms with at least N extremities.
+
+        Args:
+            min_count (int): The minimum number of extremities
+            limit (int): The maximum number of rooms to return.
+            room_id_filter (iterable[str]): room_ids to exclude from the results
+
+        Returns:
+            Deferred[list]: At most `limit` room IDs that have at least
+            `min_count` extremities, sorted by extremity count.
+        """
+
+        def _get_rooms_with_many_extremities_txn(txn):
+            where_clause = "1=1"
+            if room_id_filter:
+                where_clause = "room_id NOT IN (%s)" % (
+                    ",".join("?" for _ in room_id_filter),
+                )
+
+            sql = """
+                SELECT room_id FROM event_forward_extremities
+                WHERE %s
+                GROUP BY room_id
+                HAVING count(*) > ?
+                ORDER BY count(*) DESC
+                LIMIT ?
+            """ % (
+                where_clause,
+            )
+
+            query_args = list(itertools.chain(room_id_filter, [min_count, limit]))
+            txn.execute(sql, query_args)
+            return [room_id for room_id, in txn]
+
+        return self.db_pool.runInteraction(
+            "get_rooms_with_many_extremities", _get_rooms_with_many_extremities_txn
+        )
+
+    @cached(max_entries=5000, iterable=True)
+    def get_latest_event_ids_in_room(self, room_id):
+        return self.db_pool.simple_select_onecol(
+            table="event_forward_extremities",
+            keyvalues={"room_id": room_id},
+            retcol="event_id",
+            desc="get_latest_event_ids_in_room",
+        )
+
+    def get_min_depth(self, room_id):
+        """ For hte given room, get the minimum depth we have seen for it.
+        """
+        return self.db_pool.runInteraction(
+            "get_min_depth", self._get_min_depth_interaction, room_id
+        )
+
+    def _get_min_depth_interaction(self, txn, room_id):
+        min_depth = self.db_pool.simple_select_one_onecol_txn(
+            txn,
+            table="room_depth",
+            keyvalues={"room_id": room_id},
+            retcol="min_depth",
+            allow_none=True,
+        )
+
+        return int(min_depth) if min_depth is not None else None
+
+    def get_forward_extremeties_for_room(self, room_id, stream_ordering):
+        """For a given room_id and stream_ordering, return the forward
+        extremeties of the room at that point in "time".
+
+        Throws a StoreError if we have since purged the index for
+        stream_orderings from that point.
+
+        Args:
+            room_id (str):
+            stream_ordering (int):
+
+        Returns:
+            deferred, which resolves to a list of event_ids
+        """
+        # We want to make the cache more effective, so we clamp to the last
+        # change before the given ordering.
+        last_change = self._events_stream_cache.get_max_pos_of_last_change(room_id)
+
+        # We don't always have a full stream_to_exterm_id table, e.g. after
+        # the upgrade that introduced it, so we make sure we never ask for a
+        # stream_ordering from before a restart
+        last_change = max(self._stream_order_on_start, last_change)
+
+        # provided the last_change is recent enough, we now clamp the requested
+        # stream_ordering to it.
+        if last_change > self.stream_ordering_month_ago:
+            stream_ordering = min(last_change, stream_ordering)
+
+        return self._get_forward_extremeties_for_room(room_id, stream_ordering)
+
+    @cached(max_entries=5000, num_args=2)
+    def _get_forward_extremeties_for_room(self, room_id, stream_ordering):
+        """For a given room_id and stream_ordering, return the forward
+        extremeties of the room at that point in "time".
+
+        Throws a StoreError if we have since purged the index for
+        stream_orderings from that point.
+        """
+
+        if stream_ordering <= self.stream_ordering_month_ago:
+            raise StoreError(400, "stream_ordering too old")
+
+        sql = """
+                SELECT event_id FROM stream_ordering_to_exterm
+                INNER JOIN (
+                    SELECT room_id, MAX(stream_ordering) AS stream_ordering
+                    FROM stream_ordering_to_exterm
+                    WHERE stream_ordering <= ? GROUP BY room_id
+                ) AS rms USING (room_id, stream_ordering)
+                WHERE room_id = ?
+        """
+
+        def get_forward_extremeties_for_room_txn(txn):
+            txn.execute(sql, (stream_ordering, room_id))
+            return [event_id for event_id, in txn]
+
+        return self.db_pool.runInteraction(
+            "get_forward_extremeties_for_room", get_forward_extremeties_for_room_txn
+        )
+
+    def get_backfill_events(self, room_id, event_list, limit):
+        """Get a list of Events for a given topic that occurred before (and
+        including) the events in event_list. Return a list of max size `limit`
+
+        Args:
+            txn
+            room_id (str)
+            event_list (list)
+            limit (int)
+        """
+        return (
+            self.db_pool.runInteraction(
+                "get_backfill_events",
+                self._get_backfill_events,
+                room_id,
+                event_list,
+                limit,
+            )
+            .addCallback(self.get_events_as_list)
+            .addCallback(lambda l: sorted(l, key=lambda e: -e.depth))
+        )
+
+    def _get_backfill_events(self, txn, room_id, event_list, limit):
+        logger.debug("_get_backfill_events: %s, %r, %s", room_id, event_list, limit)
+
+        event_results = set()
+
+        # We want to make sure that we do a breadth-first, "depth" ordered
+        # search.
+
+        query = (
+            "SELECT depth, prev_event_id FROM event_edges"
+            " INNER JOIN events"
+            " ON prev_event_id = events.event_id"
+            " WHERE event_edges.event_id = ?"
+            " AND event_edges.is_state = ?"
+            " LIMIT ?"
+        )
+
+        queue = PriorityQueue()
+
+        for event_id in event_list:
+            depth = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="events",
+                keyvalues={"event_id": event_id, "room_id": room_id},
+                retcol="depth",
+                allow_none=True,
+            )
+
+            if depth:
+                queue.put((-depth, event_id))
+
+        while not queue.empty() and len(event_results) < limit:
+            try:
+                _, event_id = queue.get_nowait()
+            except Empty:
+                break
+
+            if event_id in event_results:
+                continue
+
+            event_results.add(event_id)
+
+            txn.execute(query, (event_id, False, limit - len(event_results)))
+
+            for row in txn:
+                if row[1] not in event_results:
+                    queue.put((-row[0], row[1]))
+
+        return event_results
+
+    @defer.inlineCallbacks
+    def get_missing_events(self, room_id, earliest_events, latest_events, limit):
+        ids = yield self.db_pool.runInteraction(
+            "get_missing_events",
+            self._get_missing_events,
+            room_id,
+            earliest_events,
+            latest_events,
+            limit,
+        )
+        events = yield self.get_events_as_list(ids)
+        return events
+
+    def _get_missing_events(self, txn, room_id, earliest_events, latest_events, limit):
+
+        seen_events = set(earliest_events)
+        front = set(latest_events) - seen_events
+        event_results = []
+
+        query = (
+            "SELECT prev_event_id FROM event_edges "
+            "WHERE room_id = ? AND event_id = ? AND is_state = ? "
+            "LIMIT ?"
+        )
+
+        while front and len(event_results) < limit:
+            new_front = set()
+            for event_id in front:
+                txn.execute(
+                    query, (room_id, event_id, False, limit - len(event_results))
+                )
+
+                new_results = {t[0] for t in txn} - seen_events
+
+                new_front |= new_results
+                seen_events |= new_results
+                event_results.extend(new_results)
+
+            front = new_front
+
+        # we built the list working backwards from latest_events; we now need to
+        # reverse it so that the events are approximately chronological.
+        event_results.reverse()
+        return event_results
+
+    @defer.inlineCallbacks
+    def get_successor_events(self, event_ids):
+        """Fetch all events that have the given events as a prev event
+
+        Args:
+            event_ids (iterable[str])
+
+        Returns:
+            Deferred[list[str]]
+        """
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="event_edges",
+            column="prev_event_id",
+            iterable=event_ids,
+            retcols=("event_id",),
+            desc="get_successor_events",
+        )
+
+        return [row["event_id"] for row in rows]
+
+
+class EventFederationStore(EventFederationWorkerStore):
+    """ Responsible for storing and serving up the various graphs associated
+    with an event. Including the main event graph and the auth chains for an
+    event.
+
+    Also has methods for getting the front (latest) and back (oldest) edges
+    of the event graphs. These are used to generate the parents for new events
+    and backfilling from another server respectively.
+    """
+
+    EVENT_AUTH_STATE_ONLY = "event_auth_state_only"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(EventFederationStore, self).__init__(database, db_conn, hs)
+
+        self.db_pool.updates.register_background_update_handler(
+            self.EVENT_AUTH_STATE_ONLY, self._background_delete_non_state_event_auth
+        )
+
+        hs.get_clock().looping_call(
+            self._delete_old_forward_extrem_cache, 60 * 60 * 1000
+        )
+
+    def _delete_old_forward_extrem_cache(self):
+        def _delete_old_forward_extrem_cache_txn(txn):
+            # Delete entries older than a month, while making sure we don't delete
+            # the only entries for a room.
+            sql = """
+                DELETE FROM stream_ordering_to_exterm
+                WHERE
+                room_id IN (
+                    SELECT room_id
+                    FROM stream_ordering_to_exterm
+                    WHERE stream_ordering > ?
+                ) AND stream_ordering < ?
+            """
+            txn.execute(
+                sql, (self.stream_ordering_month_ago, self.stream_ordering_month_ago)
+            )
+
+        return run_as_background_process(
+            "delete_old_forward_extrem_cache",
+            self.db_pool.runInteraction,
+            "_delete_old_forward_extrem_cache",
+            _delete_old_forward_extrem_cache_txn,
+        )
+
+    def clean_room_for_join(self, room_id):
+        return self.db_pool.runInteraction(
+            "clean_room_for_join", self._clean_room_for_join_txn, room_id
+        )
+
+    def _clean_room_for_join_txn(self, txn, room_id):
+        query = "DELETE FROM event_forward_extremities WHERE room_id = ?"
+
+        txn.execute(query, (room_id,))
+        txn.call_after(self.get_latest_event_ids_in_room.invalidate, (room_id,))
+
+    @defer.inlineCallbacks
+    def _background_delete_non_state_event_auth(self, progress, batch_size):
+        def delete_event_auth(txn):
+            target_min_stream_id = progress.get("target_min_stream_id_inclusive")
+            max_stream_id = progress.get("max_stream_id_exclusive")
+
+            if not target_min_stream_id or not max_stream_id:
+                txn.execute("SELECT COALESCE(MIN(stream_ordering), 0) FROM events")
+                rows = txn.fetchall()
+                target_min_stream_id = rows[0][0]
+
+                txn.execute("SELECT COALESCE(MAX(stream_ordering), 0) FROM events")
+                rows = txn.fetchall()
+                max_stream_id = rows[0][0]
+
+            min_stream_id = max_stream_id - batch_size
+
+            sql = """
+                DELETE FROM event_auth
+                WHERE event_id IN (
+                    SELECT event_id FROM events
+                    LEFT JOIN state_events USING (room_id, event_id)
+                    WHERE ? <= stream_ordering AND stream_ordering < ?
+                        AND state_key IS null
+                )
+            """
+
+            txn.execute(sql, (min_stream_id, max_stream_id))
+
+            new_progress = {
+                "target_min_stream_id_inclusive": target_min_stream_id,
+                "max_stream_id_exclusive": min_stream_id,
+            }
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, self.EVENT_AUTH_STATE_ONLY, new_progress
+            )
+
+            return min_stream_id >= target_min_stream_id
+
+        result = yield self.db_pool.runInteraction(
+            self.EVENT_AUTH_STATE_ONLY, delete_event_auth
+        )
+
+        if not result:
+            yield self.db_pool.updates._end_background_update(
+                self.EVENT_AUTH_STATE_ONLY
+            )
+
+        return batch_size
diff --git a/synapse/storage/databases/main/event_push_actions.py b/synapse/storage/databases/main/event_push_actions.py
new file mode 100644
index 0000000000..b8cefb4d5e
--- /dev/null
+++ b/synapse/storage/databases/main/event_push_actions.py
@@ -0,0 +1,885 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from typing import List
+
+from canonicaljson import json
+
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import LoggingTransaction, SQLBaseStore, db_to_json
+from synapse.storage.database import DatabasePool
+from synapse.util.caches.descriptors import cachedInlineCallbacks
+
+logger = logging.getLogger(__name__)
+
+
+DEFAULT_NOTIF_ACTION = ["notify", {"set_tweak": "highlight", "value": False}]
+DEFAULT_HIGHLIGHT_ACTION = [
+    "notify",
+    {"set_tweak": "sound", "value": "default"},
+    {"set_tweak": "highlight"},
+]
+
+
+def _serialize_action(actions, is_highlight):
+    """Custom serializer for actions. This allows us to "compress" common actions.
+
+    We use the fact that most users have the same actions for notifs (and for
+    highlights).
+    We store these default actions as the empty string rather than the full JSON.
+    Since the empty string isn't valid JSON there is no risk of this clashing with
+    any real JSON actions
+    """
+    if is_highlight:
+        if actions == DEFAULT_HIGHLIGHT_ACTION:
+            return ""  # We use empty string as the column is non-NULL
+    else:
+        if actions == DEFAULT_NOTIF_ACTION:
+            return ""
+    return json.dumps(actions)
+
+
+def _deserialize_action(actions, is_highlight):
+    """Custom deserializer for actions. This allows us to "compress" common actions
+    """
+    if actions:
+        return db_to_json(actions)
+
+    if is_highlight:
+        return DEFAULT_HIGHLIGHT_ACTION
+    else:
+        return DEFAULT_NOTIF_ACTION
+
+
+class EventPushActionsWorkerStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(EventPushActionsWorkerStore, self).__init__(database, db_conn, hs)
+
+        # These get correctly set by _find_stream_orderings_for_times_txn
+        self.stream_ordering_month_ago = None
+        self.stream_ordering_day_ago = None
+
+        cur = LoggingTransaction(
+            db_conn.cursor(),
+            name="_find_stream_orderings_for_times_txn",
+            database_engine=self.database_engine,
+        )
+        self._find_stream_orderings_for_times_txn(cur)
+        cur.close()
+
+        self.find_stream_orderings_looping_call = self._clock.looping_call(
+            self._find_stream_orderings_for_times, 10 * 60 * 1000
+        )
+        self._rotate_delay = 3
+        self._rotate_count = 10000
+
+    @cachedInlineCallbacks(num_args=3, tree=True, max_entries=5000)
+    def get_unread_event_push_actions_by_room_for_user(
+        self, room_id, user_id, last_read_event_id
+    ):
+        ret = yield self.db_pool.runInteraction(
+            "get_unread_event_push_actions_by_room",
+            self._get_unread_counts_by_receipt_txn,
+            room_id,
+            user_id,
+            last_read_event_id,
+        )
+        return ret
+
+    def _get_unread_counts_by_receipt_txn(
+        self, txn, room_id, user_id, last_read_event_id
+    ):
+        sql = (
+            "SELECT stream_ordering"
+            " FROM events"
+            " WHERE room_id = ? AND event_id = ?"
+        )
+        txn.execute(sql, (room_id, last_read_event_id))
+        results = txn.fetchall()
+        if len(results) == 0:
+            return {"notify_count": 0, "highlight_count": 0}
+
+        stream_ordering = results[0][0]
+
+        return self._get_unread_counts_by_pos_txn(
+            txn, room_id, user_id, stream_ordering
+        )
+
+    def _get_unread_counts_by_pos_txn(self, txn, room_id, user_id, stream_ordering):
+
+        # First get number of notifications.
+        # We don't need to put a notif=1 clause as all rows always have
+        # notif=1
+        sql = (
+            "SELECT count(*)"
+            " FROM event_push_actions ea"
+            " WHERE"
+            " user_id = ?"
+            " AND room_id = ?"
+            " AND stream_ordering > ?"
+        )
+
+        txn.execute(sql, (user_id, room_id, stream_ordering))
+        row = txn.fetchone()
+        notify_count = row[0] if row else 0
+
+        txn.execute(
+            """
+            SELECT notif_count FROM event_push_summary
+            WHERE room_id = ? AND user_id = ? AND stream_ordering > ?
+        """,
+            (room_id, user_id, stream_ordering),
+        )
+        rows = txn.fetchall()
+        if rows:
+            notify_count += rows[0][0]
+
+        # Now get the number of highlights
+        sql = (
+            "SELECT count(*)"
+            " FROM event_push_actions ea"
+            " WHERE"
+            " highlight = 1"
+            " AND user_id = ?"
+            " AND room_id = ?"
+            " AND stream_ordering > ?"
+        )
+
+        txn.execute(sql, (user_id, room_id, stream_ordering))
+        row = txn.fetchone()
+        highlight_count = row[0] if row else 0
+
+        return {"notify_count": notify_count, "highlight_count": highlight_count}
+
+    async def get_push_action_users_in_range(
+        self, min_stream_ordering, max_stream_ordering
+    ):
+        def f(txn):
+            sql = (
+                "SELECT DISTINCT(user_id) FROM event_push_actions WHERE"
+                " stream_ordering >= ? AND stream_ordering <= ?"
+            )
+            txn.execute(sql, (min_stream_ordering, max_stream_ordering))
+            return [r[0] for r in txn]
+
+        ret = await self.db_pool.runInteraction("get_push_action_users_in_range", f)
+        return ret
+
+    async def get_unread_push_actions_for_user_in_range_for_http(
+        self,
+        user_id: str,
+        min_stream_ordering: int,
+        max_stream_ordering: int,
+        limit: int = 20,
+    ) -> List[dict]:
+        """Get a list of the most recent unread push actions for a given user,
+        within the given stream ordering range. Called by the httppusher.
+
+        Args:
+            user_id: The user to fetch push actions for.
+            min_stream_ordering: The exclusive lower bound on the
+                stream ordering of event push actions to fetch.
+            max_stream_ordering: The inclusive upper bound on the
+                stream ordering of event push actions to fetch.
+            limit: The maximum number of rows to return.
+        Returns:
+            A list of dicts with the keys "event_id", "room_id", "stream_ordering", "actions".
+            The list will be ordered by ascending stream_ordering.
+            The list will have between 0~limit entries.
+        """
+        # find rooms that have a read receipt in them and return the next
+        # push actions
+        def get_after_receipt(txn):
+            # find rooms that have a read receipt in them and return the next
+            # push actions
+            sql = (
+                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
+                "   ep.highlight "
+                " FROM ("
+                "   SELECT room_id,"
+                "       MAX(stream_ordering) as stream_ordering"
+                "   FROM events"
+                "   INNER JOIN receipts_linearized USING (room_id, event_id)"
+                "   WHERE receipt_type = 'm.read' AND user_id = ?"
+                "   GROUP BY room_id"
+                ") AS rl,"
+                " event_push_actions AS ep"
+                " WHERE"
+                "   ep.room_id = rl.room_id"
+                "   AND ep.stream_ordering > rl.stream_ordering"
+                "   AND ep.user_id = ?"
+                "   AND ep.stream_ordering > ?"
+                "   AND ep.stream_ordering <= ?"
+                " ORDER BY ep.stream_ordering ASC LIMIT ?"
+            )
+            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
+            txn.execute(sql, args)
+            return txn.fetchall()
+
+        after_read_receipt = await self.db_pool.runInteraction(
+            "get_unread_push_actions_for_user_in_range_http_arr", get_after_receipt
+        )
+
+        # There are rooms with push actions in them but you don't have a read receipt in
+        # them e.g. rooms you've been invited to, so get push actions for rooms which do
+        # not have read receipts in them too.
+        def get_no_receipt(txn):
+            sql = (
+                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
+                "   ep.highlight "
+                " FROM event_push_actions AS ep"
+                " INNER JOIN events AS e USING (room_id, event_id)"
+                " WHERE"
+                "   ep.room_id NOT IN ("
+                "     SELECT room_id FROM receipts_linearized"
+                "       WHERE receipt_type = 'm.read' AND user_id = ?"
+                "       GROUP BY room_id"
+                "   )"
+                "   AND ep.user_id = ?"
+                "   AND ep.stream_ordering > ?"
+                "   AND ep.stream_ordering <= ?"
+                " ORDER BY ep.stream_ordering ASC LIMIT ?"
+            )
+            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
+            txn.execute(sql, args)
+            return txn.fetchall()
+
+        no_read_receipt = await self.db_pool.runInteraction(
+            "get_unread_push_actions_for_user_in_range_http_nrr", get_no_receipt
+        )
+
+        notifs = [
+            {
+                "event_id": row[0],
+                "room_id": row[1],
+                "stream_ordering": row[2],
+                "actions": _deserialize_action(row[3], row[4]),
+            }
+            for row in after_read_receipt + no_read_receipt
+        ]
+
+        # Now sort it so it's ordered correctly, since currently it will
+        # contain results from the first query, correctly ordered, followed
+        # by results from the second query, but we want them all ordered
+        # by stream_ordering, oldest first.
+        notifs.sort(key=lambda r: r["stream_ordering"])
+
+        # Take only up to the limit. We have to stop at the limit because
+        # one of the subqueries may have hit the limit.
+        return notifs[:limit]
+
+    async def get_unread_push_actions_for_user_in_range_for_email(
+        self,
+        user_id: str,
+        min_stream_ordering: int,
+        max_stream_ordering: int,
+        limit: int = 20,
+    ) -> List[dict]:
+        """Get a list of the most recent unread push actions for a given user,
+        within the given stream ordering range. Called by the emailpusher
+
+        Args:
+            user_id: The user to fetch push actions for.
+            min_stream_ordering: The exclusive lower bound on the
+                stream ordering of event push actions to fetch.
+            max_stream_ordering: The inclusive upper bound on the
+                stream ordering of event push actions to fetch.
+            limit: The maximum number of rows to return.
+        Returns:
+            A list of dicts with the keys "event_id", "room_id", "stream_ordering", "actions", "received_ts".
+            The list will be ordered by descending received_ts.
+            The list will have between 0~limit entries.
+        """
+        # find rooms that have a read receipt in them and return the most recent
+        # push actions
+        def get_after_receipt(txn):
+            sql = (
+                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
+                "  ep.highlight, e.received_ts"
+                " FROM ("
+                "   SELECT room_id,"
+                "       MAX(stream_ordering) as stream_ordering"
+                "   FROM events"
+                "   INNER JOIN receipts_linearized USING (room_id, event_id)"
+                "   WHERE receipt_type = 'm.read' AND user_id = ?"
+                "   GROUP BY room_id"
+                ") AS rl,"
+                " event_push_actions AS ep"
+                " INNER JOIN events AS e USING (room_id, event_id)"
+                " WHERE"
+                "   ep.room_id = rl.room_id"
+                "   AND ep.stream_ordering > rl.stream_ordering"
+                "   AND ep.user_id = ?"
+                "   AND ep.stream_ordering > ?"
+                "   AND ep.stream_ordering <= ?"
+                " ORDER BY ep.stream_ordering DESC LIMIT ?"
+            )
+            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
+            txn.execute(sql, args)
+            return txn.fetchall()
+
+        after_read_receipt = await self.db_pool.runInteraction(
+            "get_unread_push_actions_for_user_in_range_email_arr", get_after_receipt
+        )
+
+        # There are rooms with push actions in them but you don't have a read receipt in
+        # them e.g. rooms you've been invited to, so get push actions for rooms which do
+        # not have read receipts in them too.
+        def get_no_receipt(txn):
+            sql = (
+                "SELECT ep.event_id, ep.room_id, ep.stream_ordering, ep.actions,"
+                "   ep.highlight, e.received_ts"
+                " FROM event_push_actions AS ep"
+                " INNER JOIN events AS e USING (room_id, event_id)"
+                " WHERE"
+                "   ep.room_id NOT IN ("
+                "     SELECT room_id FROM receipts_linearized"
+                "       WHERE receipt_type = 'm.read' AND user_id = ?"
+                "       GROUP BY room_id"
+                "   )"
+                "   AND ep.user_id = ?"
+                "   AND ep.stream_ordering > ?"
+                "   AND ep.stream_ordering <= ?"
+                " ORDER BY ep.stream_ordering DESC LIMIT ?"
+            )
+            args = [user_id, user_id, min_stream_ordering, max_stream_ordering, limit]
+            txn.execute(sql, args)
+            return txn.fetchall()
+
+        no_read_receipt = await self.db_pool.runInteraction(
+            "get_unread_push_actions_for_user_in_range_email_nrr", get_no_receipt
+        )
+
+        # Make a list of dicts from the two sets of results.
+        notifs = [
+            {
+                "event_id": row[0],
+                "room_id": row[1],
+                "stream_ordering": row[2],
+                "actions": _deserialize_action(row[3], row[4]),
+                "received_ts": row[5],
+            }
+            for row in after_read_receipt + no_read_receipt
+        ]
+
+        # Now sort it so it's ordered correctly, since currently it will
+        # contain results from the first query, correctly ordered, followed
+        # by results from the second query, but we want them all ordered
+        # by received_ts (most recent first)
+        notifs.sort(key=lambda r: -(r["received_ts"] or 0))
+
+        # Now return the first `limit`
+        return notifs[:limit]
+
+    def get_if_maybe_push_in_range_for_user(self, user_id, min_stream_ordering):
+        """A fast check to see if there might be something to push for the
+        user since the given stream ordering. May return false positives.
+
+        Useful to know whether to bother starting a pusher on start up or not.
+
+        Args:
+            user_id (str)
+            min_stream_ordering (int)
+
+        Returns:
+            Deferred[bool]: True if there may be push to process, False if
+            there definitely isn't.
+        """
+
+        def _get_if_maybe_push_in_range_for_user_txn(txn):
+            sql = """
+                SELECT 1 FROM event_push_actions
+                WHERE user_id = ? AND stream_ordering > ?
+                LIMIT 1
+            """
+
+            txn.execute(sql, (user_id, min_stream_ordering))
+            return bool(txn.fetchone())
+
+        return self.db_pool.runInteraction(
+            "get_if_maybe_push_in_range_for_user",
+            _get_if_maybe_push_in_range_for_user_txn,
+        )
+
+    async def add_push_actions_to_staging(self, event_id, user_id_actions):
+        """Add the push actions for the event to the push action staging area.
+
+        Args:
+            event_id (str)
+            user_id_actions (dict[str, list[dict|str])]): A dictionary mapping
+                user_id to list of push actions, where an action can either be
+                a string or dict.
+
+        Returns:
+            Deferred
+        """
+
+        if not user_id_actions:
+            return
+
+        # This is a helper function for generating the necessary tuple that
+        # can be used to inert into the `event_push_actions_staging` table.
+        def _gen_entry(user_id, actions):
+            is_highlight = 1 if _action_has_highlight(actions) else 0
+            return (
+                event_id,  # event_id column
+                user_id,  # user_id column
+                _serialize_action(actions, is_highlight),  # actions column
+                1,  # notif column
+                is_highlight,  # highlight column
+            )
+
+        def _add_push_actions_to_staging_txn(txn):
+            # We don't use simple_insert_many here to avoid the overhead
+            # of generating lists of dicts.
+
+            sql = """
+                INSERT INTO event_push_actions_staging
+                    (event_id, user_id, actions, notif, highlight)
+                VALUES (?, ?, ?, ?, ?)
+            """
+
+            txn.executemany(
+                sql,
+                (
+                    _gen_entry(user_id, actions)
+                    for user_id, actions in user_id_actions.items()
+                ),
+            )
+
+        return await self.db_pool.runInteraction(
+            "add_push_actions_to_staging", _add_push_actions_to_staging_txn
+        )
+
+    async def remove_push_actions_from_staging(self, event_id: str) -> None:
+        """Called if we failed to persist the event to ensure that stale push
+        actions don't build up in the DB
+        """
+
+        try:
+            res = await self.db_pool.simple_delete(
+                table="event_push_actions_staging",
+                keyvalues={"event_id": event_id},
+                desc="remove_push_actions_from_staging",
+            )
+            return res
+        except Exception:
+            # this method is called from an exception handler, so propagating
+            # another exception here really isn't helpful - there's nothing
+            # the caller can do about it. Just log the exception and move on.
+            logger.exception(
+                "Error removing push actions after event persistence failure"
+            )
+
+    def _find_stream_orderings_for_times(self):
+        return run_as_background_process(
+            "event_push_action_stream_orderings",
+            self.db_pool.runInteraction,
+            "_find_stream_orderings_for_times",
+            self._find_stream_orderings_for_times_txn,
+        )
+
+    def _find_stream_orderings_for_times_txn(self, txn):
+        logger.info("Searching for stream ordering 1 month ago")
+        self.stream_ordering_month_ago = self._find_first_stream_ordering_after_ts_txn(
+            txn, self._clock.time_msec() - 30 * 24 * 60 * 60 * 1000
+        )
+        logger.info(
+            "Found stream ordering 1 month ago: it's %d", self.stream_ordering_month_ago
+        )
+        logger.info("Searching for stream ordering 1 day ago")
+        self.stream_ordering_day_ago = self._find_first_stream_ordering_after_ts_txn(
+            txn, self._clock.time_msec() - 24 * 60 * 60 * 1000
+        )
+        logger.info(
+            "Found stream ordering 1 day ago: it's %d", self.stream_ordering_day_ago
+        )
+
+    def find_first_stream_ordering_after_ts(self, ts):
+        """Gets the stream ordering corresponding to a given timestamp.
+
+        Specifically, finds the stream_ordering of the first event that was
+        received on or after the timestamp. This is done by a binary search on
+        the events table, since there is no index on received_ts, so is
+        relatively slow.
+
+        Args:
+            ts (int): timestamp in millis
+
+        Returns:
+            Deferred[int]: stream ordering of the first event received on/after
+                the timestamp
+        """
+        return self.db_pool.runInteraction(
+            "_find_first_stream_ordering_after_ts_txn",
+            self._find_first_stream_ordering_after_ts_txn,
+            ts,
+        )
+
+    @staticmethod
+    def _find_first_stream_ordering_after_ts_txn(txn, ts):
+        """
+        Find the stream_ordering of the first event that was received on or
+        after a given timestamp. This is relatively slow as there is no index
+        on received_ts but we can then use this to delete push actions before
+        this.
+
+        received_ts must necessarily be in the same order as stream_ordering
+        and stream_ordering is indexed, so we manually binary search using
+        stream_ordering
+
+        Args:
+            txn (twisted.enterprise.adbapi.Transaction):
+            ts (int): timestamp to search for
+
+        Returns:
+            int: stream ordering
+        """
+        txn.execute("SELECT MAX(stream_ordering) FROM events")
+        max_stream_ordering = txn.fetchone()[0]
+
+        if max_stream_ordering is None:
+            return 0
+
+        # We want the first stream_ordering in which received_ts is greater
+        # than or equal to ts. Call this point X.
+        #
+        # We maintain the invariants:
+        #
+        #   range_start <= X <= range_end
+        #
+        range_start = 0
+        range_end = max_stream_ordering + 1
+
+        # Given a stream_ordering, look up the timestamp at that
+        # stream_ordering.
+        #
+        # The array may be sparse (we may be missing some stream_orderings).
+        # We treat the gaps as the same as having the same value as the
+        # preceding entry, because we will pick the lowest stream_ordering
+        # which satisfies our requirement of received_ts >= ts.
+        #
+        # For example, if our array of events indexed by stream_ordering is
+        # [10, <none>, 20], we should treat this as being equivalent to
+        # [10, 10, 20].
+        #
+        sql = (
+            "SELECT received_ts FROM events"
+            " WHERE stream_ordering <= ?"
+            " ORDER BY stream_ordering DESC"
+            " LIMIT 1"
+        )
+
+        while range_end - range_start > 0:
+            middle = (range_end + range_start) // 2
+            txn.execute(sql, (middle,))
+            row = txn.fetchone()
+            if row is None:
+                # no rows with stream_ordering<=middle
+                range_start = middle + 1
+                continue
+
+            middle_ts = row[0]
+            if ts > middle_ts:
+                # we got a timestamp lower than the one we were looking for.
+                # definitely need to look higher: X > middle.
+                range_start = middle + 1
+            else:
+                # we got a timestamp higher than (or the same as) the one we
+                # were looking for. We aren't yet sure about the point we
+                # looked up, but we can be sure that X <= middle.
+                range_end = middle
+
+        return range_end
+
+    async def get_time_of_last_push_action_before(self, stream_ordering):
+        def f(txn):
+            sql = (
+                "SELECT e.received_ts"
+                " FROM event_push_actions AS ep"
+                " JOIN events e ON ep.room_id = e.room_id AND ep.event_id = e.event_id"
+                " WHERE ep.stream_ordering > ?"
+                " ORDER BY ep.stream_ordering ASC"
+                " LIMIT 1"
+            )
+            txn.execute(sql, (stream_ordering,))
+            return txn.fetchone()
+
+        result = await self.db_pool.runInteraction(
+            "get_time_of_last_push_action_before", f
+        )
+        return result[0] if result else None
+
+
+class EventPushActionsStore(EventPushActionsWorkerStore):
+    EPA_HIGHLIGHT_INDEX = "epa_highlight_index"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(EventPushActionsStore, self).__init__(database, db_conn, hs)
+
+        self.db_pool.updates.register_background_index_update(
+            self.EPA_HIGHLIGHT_INDEX,
+            index_name="event_push_actions_u_highlight",
+            table="event_push_actions",
+            columns=["user_id", "stream_ordering"],
+        )
+
+        self.db_pool.updates.register_background_index_update(
+            "event_push_actions_highlights_index",
+            index_name="event_push_actions_highlights_index",
+            table="event_push_actions",
+            columns=["user_id", "room_id", "topological_ordering", "stream_ordering"],
+            where_clause="highlight=1",
+        )
+
+        self._doing_notif_rotation = False
+        self._rotate_notif_loop = self._clock.looping_call(
+            self._start_rotate_notifs, 30 * 60 * 1000
+        )
+
+    async def get_push_actions_for_user(
+        self, user_id, before=None, limit=50, only_highlight=False
+    ):
+        def f(txn):
+            before_clause = ""
+            if before:
+                before_clause = "AND epa.stream_ordering < ?"
+                args = [user_id, before, limit]
+            else:
+                args = [user_id, limit]
+
+            if only_highlight:
+                if len(before_clause) > 0:
+                    before_clause += " "
+                before_clause += "AND epa.highlight = 1"
+
+            # NB. This assumes event_ids are globally unique since
+            # it makes the query easier to index
+            sql = (
+                "SELECT epa.event_id, epa.room_id,"
+                " epa.stream_ordering, epa.topological_ordering,"
+                " epa.actions, epa.highlight, epa.profile_tag, e.received_ts"
+                " FROM event_push_actions epa, events e"
+                " WHERE epa.event_id = e.event_id"
+                " AND epa.user_id = ? %s"
+                " ORDER BY epa.stream_ordering DESC"
+                " LIMIT ?" % (before_clause,)
+            )
+            txn.execute(sql, args)
+            return self.db_pool.cursor_to_dict(txn)
+
+        push_actions = await self.db_pool.runInteraction("get_push_actions_for_user", f)
+        for pa in push_actions:
+            pa["actions"] = _deserialize_action(pa["actions"], pa["highlight"])
+        return push_actions
+
+    async def get_latest_push_action_stream_ordering(self):
+        def f(txn):
+            txn.execute("SELECT MAX(stream_ordering) FROM event_push_actions")
+            return txn.fetchone()
+
+        result = await self.db_pool.runInteraction(
+            "get_latest_push_action_stream_ordering", f
+        )
+        return result[0] or 0
+
+    def _remove_old_push_actions_before_txn(
+        self, txn, room_id, user_id, stream_ordering
+    ):
+        """
+        Purges old push actions for a user and room before a given
+        stream_ordering.
+
+        We however keep a months worth of highlighted notifications, so that
+        users can still get a list of recent highlights.
+
+        Args:
+            txn: The transcation
+            room_id: Room ID to delete from
+            user_id: user ID to delete for
+            stream_ordering: The lowest stream ordering which will
+                                  not be deleted.
+        """
+        txn.call_after(
+            self.get_unread_event_push_actions_by_room_for_user.invalidate_many,
+            (room_id, user_id),
+        )
+
+        # We need to join on the events table to get the received_ts for
+        # event_push_actions and sqlite won't let us use a join in a delete so
+        # we can't just delete where received_ts < x. Furthermore we can
+        # only identify event_push_actions by a tuple of room_id, event_id
+        # we we can't use a subquery.
+        # Instead, we look up the stream ordering for the last event in that
+        # room received before the threshold time and delete event_push_actions
+        # in the room with a stream_odering before that.
+        txn.execute(
+            "DELETE FROM event_push_actions "
+            " WHERE user_id = ? AND room_id = ? AND "
+            " stream_ordering <= ?"
+            " AND ((stream_ordering < ? AND highlight = 1) or highlight = 0)",
+            (user_id, room_id, stream_ordering, self.stream_ordering_month_ago),
+        )
+
+        txn.execute(
+            """
+            DELETE FROM event_push_summary
+            WHERE room_id = ? AND user_id = ? AND stream_ordering <= ?
+        """,
+            (room_id, user_id, stream_ordering),
+        )
+
+    def _start_rotate_notifs(self):
+        return run_as_background_process("rotate_notifs", self._rotate_notifs)
+
+    async def _rotate_notifs(self):
+        if self._doing_notif_rotation or self.stream_ordering_day_ago is None:
+            return
+        self._doing_notif_rotation = True
+
+        try:
+            while True:
+                logger.info("Rotating notifications")
+
+                caught_up = await self.db_pool.runInteraction(
+                    "_rotate_notifs", self._rotate_notifs_txn
+                )
+                if caught_up:
+                    break
+                await self.hs.get_clock().sleep(self._rotate_delay)
+        finally:
+            self._doing_notif_rotation = False
+
+    def _rotate_notifs_txn(self, txn):
+        """Archives older notifications into event_push_summary. Returns whether
+        the archiving process has caught up or not.
+        """
+
+        old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn(
+            txn,
+            table="event_push_summary_stream_ordering",
+            keyvalues={},
+            retcol="stream_ordering",
+        )
+
+        # We don't to try and rotate millions of rows at once, so we cap the
+        # maximum stream ordering we'll rotate before.
+        txn.execute(
+            """
+            SELECT stream_ordering FROM event_push_actions
+            WHERE stream_ordering > ?
+            ORDER BY stream_ordering ASC LIMIT 1 OFFSET ?
+        """,
+            (old_rotate_stream_ordering, self._rotate_count),
+        )
+        stream_row = txn.fetchone()
+        if stream_row:
+            (offset_stream_ordering,) = stream_row
+            rotate_to_stream_ordering = min(
+                self.stream_ordering_day_ago, offset_stream_ordering
+            )
+            caught_up = offset_stream_ordering >= self.stream_ordering_day_ago
+        else:
+            rotate_to_stream_ordering = self.stream_ordering_day_ago
+            caught_up = True
+
+        logger.info("Rotating notifications up to: %s", rotate_to_stream_ordering)
+
+        self._rotate_notifs_before_txn(txn, rotate_to_stream_ordering)
+
+        # We have caught up iff we were limited by `stream_ordering_day_ago`
+        return caught_up
+
+    def _rotate_notifs_before_txn(self, txn, rotate_to_stream_ordering):
+        old_rotate_stream_ordering = self.db_pool.simple_select_one_onecol_txn(
+            txn,
+            table="event_push_summary_stream_ordering",
+            keyvalues={},
+            retcol="stream_ordering",
+        )
+
+        # Calculate the new counts that should be upserted into event_push_summary
+        sql = """
+            SELECT user_id, room_id,
+                coalesce(old.notif_count, 0) + upd.notif_count,
+                upd.stream_ordering,
+                old.user_id
+            FROM (
+                SELECT user_id, room_id, count(*) as notif_count,
+                    max(stream_ordering) as stream_ordering
+                FROM event_push_actions
+                WHERE ? <= stream_ordering AND stream_ordering < ?
+                    AND highlight = 0
+                GROUP BY user_id, room_id
+            ) AS upd
+            LEFT JOIN event_push_summary AS old USING (user_id, room_id)
+        """
+
+        txn.execute(sql, (old_rotate_stream_ordering, rotate_to_stream_ordering))
+        rows = txn.fetchall()
+
+        logger.info("Rotating notifications, handling %d rows", len(rows))
+
+        # If the `old.user_id` above is NULL then we know there isn't already an
+        # entry in the table, so we simply insert it. Otherwise we update the
+        # existing table.
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="event_push_summary",
+            values=[
+                {
+                    "user_id": row[0],
+                    "room_id": row[1],
+                    "notif_count": row[2],
+                    "stream_ordering": row[3],
+                }
+                for row in rows
+                if row[4] is None
+            ],
+        )
+
+        txn.executemany(
+            """
+                UPDATE event_push_summary SET notif_count = ?, stream_ordering = ?
+                WHERE user_id = ? AND room_id = ?
+            """,
+            ((row[2], row[3], row[0], row[1]) for row in rows if row[4] is not None),
+        )
+
+        txn.execute(
+            "DELETE FROM event_push_actions"
+            " WHERE ? <= stream_ordering AND stream_ordering < ? AND highlight = 0",
+            (old_rotate_stream_ordering, rotate_to_stream_ordering),
+        )
+
+        logger.info("Rotating notifications, deleted %s push actions", txn.rowcount)
+
+        txn.execute(
+            "UPDATE event_push_summary_stream_ordering SET stream_ordering = ?",
+            (rotate_to_stream_ordering,),
+        )
+
+
+def _action_has_highlight(actions):
+    for action in actions:
+        try:
+            if action.get("set_tweak", None) == "highlight":
+                return action.get("value", True)
+        except AttributeError:
+            pass
+
+    return False
diff --git a/synapse/storage/databases/main/events.py b/synapse/storage/databases/main/events.py
new file mode 100644
index 0000000000..4d8a24ce4b
--- /dev/null
+++ b/synapse/storage/databases/main/events.py
@@ -0,0 +1,1527 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018-2019 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import itertools
+import logging
+from collections import OrderedDict, namedtuple
+from typing import TYPE_CHECKING, Dict, Iterable, List, Tuple
+
+import attr
+from prometheus_client import Counter
+
+from twisted.internet import defer
+
+import synapse.metrics
+from synapse.api.constants import EventContentFields, EventTypes, RelationTypes
+from synapse.api.room_versions import RoomVersions
+from synapse.crypto.event_signing import compute_event_reference_hash
+from synapse.events import EventBase  # noqa: F401
+from synapse.events.snapshot import EventContext  # noqa: F401
+from synapse.logging.utils import log_function
+from synapse.storage._base import db_to_json, make_in_list_sql_clause
+from synapse.storage.database import DatabasePool, LoggingTransaction
+from synapse.storage.databases.main.search import SearchEntry
+from synapse.storage.util.id_generators import StreamIdGenerator
+from synapse.types import StateMap, get_domain_from_id
+from synapse.util.frozenutils import frozendict_json_encoder
+from synapse.util.iterutils import batch_iter
+
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+    from synapse.storage.databases.main import DataStore
+
+
+logger = logging.getLogger(__name__)
+
+persist_event_counter = Counter("synapse_storage_events_persisted_events", "")
+event_counter = Counter(
+    "synapse_storage_events_persisted_events_sep",
+    "",
+    ["type", "origin_type", "origin_entity"],
+)
+
+STATE_EVENT_TYPES_TO_MARK_UNREAD = {
+    EventTypes.Topic,
+    EventTypes.Name,
+    EventTypes.RoomAvatar,
+    EventTypes.Tombstone,
+}
+
+
+def should_count_as_unread(event: EventBase, context: EventContext) -> bool:
+    # Exclude rejected and soft-failed events.
+    if context.rejected or event.internal_metadata.is_soft_failed():
+        return False
+
+    # Exclude notices.
+    if (
+        not event.is_state()
+        and event.type == EventTypes.Message
+        and event.content.get("msgtype") == "m.notice"
+    ):
+        return False
+
+    # Exclude edits.
+    relates_to = event.content.get("m.relates_to", {})
+    if relates_to.get("rel_type") == RelationTypes.REPLACE:
+        return False
+
+    # Mark events that have a non-empty string body as unread.
+    body = event.content.get("body")
+    if isinstance(body, str) and body:
+        return True
+
+    # Mark some state events as unread.
+    if event.is_state() and event.type in STATE_EVENT_TYPES_TO_MARK_UNREAD:
+        return True
+
+    # Mark encrypted events as unread.
+    if not event.is_state() and event.type == EventTypes.Encrypted:
+        return True
+
+    return False
+
+
+def encode_json(json_object):
+    """
+    Encode a Python object as JSON and return it in a Unicode string.
+    """
+    out = frozendict_json_encoder.encode(json_object)
+    if isinstance(out, bytes):
+        out = out.decode("utf8")
+    return out
+
+
+_EventCacheEntry = namedtuple("_EventCacheEntry", ("event", "redacted_event"))
+
+
+@attr.s(slots=True)
+class DeltaState:
+    """Deltas to use to update the `current_state_events` table.
+
+    Attributes:
+        to_delete: List of type/state_keys to delete from current state
+        to_insert: Map of state to upsert into current state
+        no_longer_in_room: The server is not longer in the room, so the room
+            should e.g. be removed from `current_state_events` table.
+    """
+
+    to_delete = attr.ib(type=List[Tuple[str, str]])
+    to_insert = attr.ib(type=StateMap[str])
+    no_longer_in_room = attr.ib(type=bool, default=False)
+
+
+class PersistEventsStore:
+    """Contains all the functions for writing events to the database.
+
+    Should only be instantiated on one process (when using a worker mode setup).
+
+    Note: This is not part of the `DataStore` mixin.
+    """
+
+    def __init__(
+        self, hs: "HomeServer", db: DatabasePool, main_data_store: "DataStore"
+    ):
+        self.hs = hs
+        self.db_pool = db
+        self.store = main_data_store
+        self.database_engine = db.engine
+        self._clock = hs.get_clock()
+
+        self._ephemeral_messages_enabled = hs.config.enable_ephemeral_messages
+        self.is_mine_id = hs.is_mine_id
+
+        # Ideally we'd move these ID gens here, unfortunately some other ID
+        # generators are chained off them so doing so is a bit of a PITA.
+        self._backfill_id_gen = self.store._backfill_id_gen  # type: StreamIdGenerator
+        self._stream_id_gen = self.store._stream_id_gen  # type: StreamIdGenerator
+
+        # This should only exist on instances that are configured to write
+        assert (
+            hs.config.worker.writers.events == hs.get_instance_name()
+        ), "Can only instantiate EventsStore on master"
+
+    @defer.inlineCallbacks
+    def _persist_events_and_state_updates(
+        self,
+        events_and_contexts: List[Tuple[EventBase, EventContext]],
+        current_state_for_room: Dict[str, StateMap[str]],
+        state_delta_for_room: Dict[str, DeltaState],
+        new_forward_extremeties: Dict[str, List[str]],
+        backfilled: bool = False,
+    ):
+        """Persist a set of events alongside updates to the current state and
+        forward extremities tables.
+
+        Args:
+            events_and_contexts:
+            current_state_for_room: Map from room_id to the current state of
+                the room based on forward extremities
+            state_delta_for_room: Map from room_id to the delta to apply to
+                room state
+            new_forward_extremities: Map from room_id to list of event IDs
+                that are the new forward extremities of the room.
+            backfilled
+
+        Returns:
+            Deferred: resolves when the events have been persisted
+        """
+
+        # We want to calculate the stream orderings as late as possible, as
+        # we only notify after all events with a lesser stream ordering have
+        # been persisted. I.e. if we spend 10s inside the with block then
+        # that will delay all subsequent events from being notified about.
+        # Hence why we do it down here rather than wrapping the entire
+        # function.
+        #
+        # Its safe to do this after calculating the state deltas etc as we
+        # only need to protect the *persistence* of the events. This is to
+        # ensure that queries of the form "fetch events since X" don't
+        # return events and stream positions after events that are still in
+        # flight, as otherwise subsequent requests "fetch event since Y"
+        # will not return those events.
+        #
+        # Note: Multiple instances of this function cannot be in flight at
+        # the same time for the same room.
+        if backfilled:
+            stream_ordering_manager = self._backfill_id_gen.get_next_mult(
+                len(events_and_contexts)
+            )
+        else:
+            stream_ordering_manager = self._stream_id_gen.get_next_mult(
+                len(events_and_contexts)
+            )
+
+        with stream_ordering_manager as stream_orderings:
+            for (event, context), stream in zip(events_and_contexts, stream_orderings):
+                event.internal_metadata.stream_ordering = stream
+
+            yield self.db_pool.runInteraction(
+                "persist_events",
+                self._persist_events_txn,
+                events_and_contexts=events_and_contexts,
+                backfilled=backfilled,
+                state_delta_for_room=state_delta_for_room,
+                new_forward_extremeties=new_forward_extremeties,
+            )
+            persist_event_counter.inc(len(events_and_contexts))
+
+            if not backfilled:
+                # backfilled events have negative stream orderings, so we don't
+                # want to set the event_persisted_position to that.
+                synapse.metrics.event_persisted_position.set(
+                    events_and_contexts[-1][0].internal_metadata.stream_ordering
+                )
+
+            for event, context in events_and_contexts:
+                if context.app_service:
+                    origin_type = "local"
+                    origin_entity = context.app_service.id
+                elif self.hs.is_mine_id(event.sender):
+                    origin_type = "local"
+                    origin_entity = "*client*"
+                else:
+                    origin_type = "remote"
+                    origin_entity = get_domain_from_id(event.sender)
+
+                event_counter.labels(event.type, origin_type, origin_entity).inc()
+
+                self.store.get_unread_message_count_for_user.invalidate_many(
+                    (event.room_id,),
+                )
+
+            for room_id, new_state in current_state_for_room.items():
+                self.store.get_current_state_ids.prefill((room_id,), new_state)
+
+            for room_id, latest_event_ids in new_forward_extremeties.items():
+                self.store.get_latest_event_ids_in_room.prefill(
+                    (room_id,), list(latest_event_ids)
+                )
+
+    @defer.inlineCallbacks
+    def _get_events_which_are_prevs(self, event_ids):
+        """Filter the supplied list of event_ids to get those which are prev_events of
+        existing (non-outlier/rejected) events.
+
+        Args:
+            event_ids (Iterable[str]): event ids to filter
+
+        Returns:
+            Deferred[List[str]]: filtered event ids
+        """
+        results = []
+
+        def _get_events_which_are_prevs_txn(txn, batch):
+            sql = """
+            SELECT prev_event_id, internal_metadata
+            FROM event_edges
+                INNER JOIN events USING (event_id)
+                LEFT JOIN rejections USING (event_id)
+                LEFT JOIN event_json USING (event_id)
+            WHERE
+                NOT events.outlier
+                AND rejections.event_id IS NULL
+                AND
+            """
+
+            clause, args = make_in_list_sql_clause(
+                self.database_engine, "prev_event_id", batch
+            )
+
+            txn.execute(sql + clause, args)
+            results.extend(r[0] for r in txn if not db_to_json(r[1]).get("soft_failed"))
+
+        for chunk in batch_iter(event_ids, 100):
+            yield self.db_pool.runInteraction(
+                "_get_events_which_are_prevs", _get_events_which_are_prevs_txn, chunk
+            )
+
+        return results
+
+    @defer.inlineCallbacks
+    def _get_prevs_before_rejected(self, event_ids):
+        """Get soft-failed ancestors to remove from the extremities.
+
+        Given a set of events, find all those that have been soft-failed or
+        rejected. Returns those soft failed/rejected events and their prev
+        events (whether soft-failed/rejected or not), and recurses up the
+        prev-event graph until it finds no more soft-failed/rejected events.
+
+        This is used to find extremities that are ancestors of new events, but
+        are separated by soft failed events.
+
+        Args:
+            event_ids (Iterable[str]): Events to find prev events for. Note
+                that these must have already been persisted.
+
+        Returns:
+            Deferred[set[str]]
+        """
+
+        # The set of event_ids to return. This includes all soft-failed events
+        # and their prev events.
+        existing_prevs = set()
+
+        def _get_prevs_before_rejected_txn(txn, batch):
+            to_recursively_check = batch
+
+            while to_recursively_check:
+                sql = """
+                SELECT
+                    event_id, prev_event_id, internal_metadata,
+                    rejections.event_id IS NOT NULL
+                FROM event_edges
+                    INNER JOIN events USING (event_id)
+                    LEFT JOIN rejections USING (event_id)
+                    LEFT JOIN event_json USING (event_id)
+                WHERE
+                    NOT events.outlier
+                    AND
+                """
+
+                clause, args = make_in_list_sql_clause(
+                    self.database_engine, "event_id", to_recursively_check
+                )
+
+                txn.execute(sql + clause, args)
+                to_recursively_check = []
+
+                for event_id, prev_event_id, metadata, rejected in txn:
+                    if prev_event_id in existing_prevs:
+                        continue
+
+                    soft_failed = db_to_json(metadata).get("soft_failed")
+                    if soft_failed or rejected:
+                        to_recursively_check.append(prev_event_id)
+                        existing_prevs.add(prev_event_id)
+
+        for chunk in batch_iter(event_ids, 100):
+            yield self.db_pool.runInteraction(
+                "_get_prevs_before_rejected", _get_prevs_before_rejected_txn, chunk
+            )
+
+        return existing_prevs
+
+    @log_function
+    def _persist_events_txn(
+        self,
+        txn: LoggingTransaction,
+        events_and_contexts: List[Tuple[EventBase, EventContext]],
+        backfilled: bool,
+        state_delta_for_room: Dict[str, DeltaState] = {},
+        new_forward_extremeties: Dict[str, List[str]] = {},
+    ):
+        """Insert some number of room events into the necessary database tables.
+
+        Rejected events are only inserted into the events table, the events_json table,
+        and the rejections table. Things reading from those table will need to check
+        whether the event was rejected.
+
+        Args:
+            txn
+            events_and_contexts: events to persist
+            backfilled: True if the events were backfilled
+            delete_existing True to purge existing table rows for the events
+                from the database. This is useful when retrying due to
+                IntegrityError.
+            state_delta_for_room: The current-state delta for each room.
+            new_forward_extremetie: The new forward extremities for each room.
+                For each room, a list of the event ids which are the forward
+                extremities.
+
+        """
+        all_events_and_contexts = events_and_contexts
+
+        min_stream_order = events_and_contexts[0][0].internal_metadata.stream_ordering
+        max_stream_order = events_and_contexts[-1][0].internal_metadata.stream_ordering
+
+        self._update_forward_extremities_txn(
+            txn,
+            new_forward_extremities=new_forward_extremeties,
+            max_stream_order=max_stream_order,
+        )
+
+        # Ensure that we don't have the same event twice.
+        events_and_contexts = self._filter_events_and_contexts_for_duplicates(
+            events_and_contexts
+        )
+
+        self._update_room_depths_txn(
+            txn, events_and_contexts=events_and_contexts, backfilled=backfilled
+        )
+
+        # _update_outliers_txn filters out any events which have already been
+        # persisted, and returns the filtered list.
+        events_and_contexts = self._update_outliers_txn(
+            txn, events_and_contexts=events_and_contexts
+        )
+
+        # From this point onwards the events are only events that we haven't
+        # seen before.
+
+        self._store_event_txn(txn, events_and_contexts=events_and_contexts)
+
+        # Insert into event_to_state_groups.
+        self._store_event_state_mappings_txn(txn, events_and_contexts)
+
+        # We want to store event_auth mappings for rejected events, as they're
+        # used in state res v2.
+        # This is only necessary if the rejected event appears in an accepted
+        # event's auth chain, but its easier for now just to store them (and
+        # it doesn't take much storage compared to storing the entire event
+        # anyway).
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="event_auth",
+            values=[
+                {
+                    "event_id": event.event_id,
+                    "room_id": event.room_id,
+                    "auth_id": auth_id,
+                }
+                for event, _ in events_and_contexts
+                for auth_id in event.auth_event_ids()
+                if event.is_state()
+            ],
+        )
+
+        # _store_rejected_events_txn filters out any events which were
+        # rejected, and returns the filtered list.
+        events_and_contexts = self._store_rejected_events_txn(
+            txn, events_and_contexts=events_and_contexts
+        )
+
+        # From this point onwards the events are only ones that weren't
+        # rejected.
+
+        self._update_metadata_tables_txn(
+            txn,
+            events_and_contexts=events_and_contexts,
+            all_events_and_contexts=all_events_and_contexts,
+            backfilled=backfilled,
+        )
+
+        # We call this last as it assumes we've inserted the events into
+        # room_memberships, where applicable.
+        self._update_current_state_txn(txn, state_delta_for_room, min_stream_order)
+
+    def _update_current_state_txn(
+        self,
+        txn: LoggingTransaction,
+        state_delta_by_room: Dict[str, DeltaState],
+        stream_id: int,
+    ):
+        for room_id, delta_state in state_delta_by_room.items():
+            to_delete = delta_state.to_delete
+            to_insert = delta_state.to_insert
+
+            if delta_state.no_longer_in_room:
+                # Server is no longer in the room so we delete the room from
+                # current_state_events, being careful we've already updated the
+                # rooms.room_version column (which gets populated in a
+                # background task).
+                self._upsert_room_version_txn(txn, room_id)
+
+                # Before deleting we populate the current_state_delta_stream
+                # so that async background tasks get told what happened.
+                sql = """
+                    INSERT INTO current_state_delta_stream
+                        (stream_id, room_id, type, state_key, event_id, prev_event_id)
+                    SELECT ?, room_id, type, state_key, null, event_id
+                        FROM current_state_events
+                        WHERE room_id = ?
+                """
+                txn.execute(sql, (stream_id, room_id))
+
+                self.db_pool.simple_delete_txn(
+                    txn, table="current_state_events", keyvalues={"room_id": room_id},
+                )
+            else:
+                # We're still in the room, so we update the current state as normal.
+
+                # First we add entries to the current_state_delta_stream. We
+                # do this before updating the current_state_events table so
+                # that we can use it to calculate the `prev_event_id`. (This
+                # allows us to not have to pull out the existing state
+                # unnecessarily).
+                #
+                # The stream_id for the update is chosen to be the minimum of the stream_ids
+                # for the batch of the events that we are persisting; that means we do not
+                # end up in a situation where workers see events before the
+                # current_state_delta updates.
+                #
+                sql = """
+                    INSERT INTO current_state_delta_stream
+                    (stream_id, room_id, type, state_key, event_id, prev_event_id)
+                    SELECT ?, ?, ?, ?, ?, (
+                        SELECT event_id FROM current_state_events
+                        WHERE room_id = ? AND type = ? AND state_key = ?
+                    )
+                """
+                txn.executemany(
+                    sql,
+                    (
+                        (
+                            stream_id,
+                            room_id,
+                            etype,
+                            state_key,
+                            to_insert.get((etype, state_key)),
+                            room_id,
+                            etype,
+                            state_key,
+                        )
+                        for etype, state_key in itertools.chain(to_delete, to_insert)
+                    ),
+                )
+                # Now we actually update the current_state_events table
+
+                txn.executemany(
+                    "DELETE FROM current_state_events"
+                    " WHERE room_id = ? AND type = ? AND state_key = ?",
+                    (
+                        (room_id, etype, state_key)
+                        for etype, state_key in itertools.chain(to_delete, to_insert)
+                    ),
+                )
+
+                # We include the membership in the current state table, hence we do
+                # a lookup when we insert. This assumes that all events have already
+                # been inserted into room_memberships.
+                txn.executemany(
+                    """INSERT INTO current_state_events
+                        (room_id, type, state_key, event_id, membership)
+                    VALUES (?, ?, ?, ?, (SELECT membership FROM room_memberships WHERE event_id = ?))
+                    """,
+                    [
+                        (room_id, key[0], key[1], ev_id, ev_id)
+                        for key, ev_id in to_insert.items()
+                    ],
+                )
+
+            # We now update `local_current_membership`. We do this regardless
+            # of whether we're still in the room or not to handle the case where
+            # e.g. we just got banned (where we need to record that fact here).
+
+            # Note: Do we really want to delete rows here (that we do not
+            # subsequently reinsert below)? While technically correct it means
+            # we have no record of the fact the user *was* a member of the
+            # room but got, say, state reset out of it.
+            if to_delete or to_insert:
+                txn.executemany(
+                    "DELETE FROM local_current_membership"
+                    " WHERE room_id = ? AND user_id = ?",
+                    (
+                        (room_id, state_key)
+                        for etype, state_key in itertools.chain(to_delete, to_insert)
+                        if etype == EventTypes.Member and self.is_mine_id(state_key)
+                    ),
+                )
+
+            if to_insert:
+                txn.executemany(
+                    """INSERT INTO local_current_membership
+                        (room_id, user_id, event_id, membership)
+                    VALUES (?, ?, ?, (SELECT membership FROM room_memberships WHERE event_id = ?))
+                    """,
+                    [
+                        (room_id, key[1], ev_id, ev_id)
+                        for key, ev_id in to_insert.items()
+                        if key[0] == EventTypes.Member and self.is_mine_id(key[1])
+                    ],
+                )
+
+            txn.call_after(
+                self.store._curr_state_delta_stream_cache.entity_has_changed,
+                room_id,
+                stream_id,
+            )
+
+            # Invalidate the various caches
+
+            # Figure out the changes of membership to invalidate the
+            # `get_rooms_for_user` cache.
+            # We find out which membership events we may have deleted
+            # and which we have added, then we invlidate the caches for all
+            # those users.
+            members_changed = {
+                state_key
+                for ev_type, state_key in itertools.chain(to_delete, to_insert)
+                if ev_type == EventTypes.Member
+            }
+
+            for member in members_changed:
+                txn.call_after(
+                    self.store.get_rooms_for_user_with_stream_ordering.invalidate,
+                    (member,),
+                )
+
+            self.store._invalidate_state_caches_and_stream(
+                txn, room_id, members_changed
+            )
+
+    def _upsert_room_version_txn(self, txn: LoggingTransaction, room_id: str):
+        """Update the room version in the database based off current state
+        events.
+
+        This is used when we're about to delete current state and we want to
+        ensure that the `rooms.room_version` column is up to date.
+        """
+
+        sql = """
+            SELECT json FROM event_json
+            INNER JOIN current_state_events USING (room_id, event_id)
+            WHERE room_id = ? AND type = ? AND state_key = ?
+        """
+        txn.execute(sql, (room_id, EventTypes.Create, ""))
+        row = txn.fetchone()
+        if row:
+            event_json = db_to_json(row[0])
+            content = event_json.get("content", {})
+            creator = content.get("creator")
+            room_version_id = content.get("room_version", RoomVersions.V1.identifier)
+
+            self.db_pool.simple_upsert_txn(
+                txn,
+                table="rooms",
+                keyvalues={"room_id": room_id},
+                values={"room_version": room_version_id},
+                insertion_values={"is_public": False, "creator": creator},
+            )
+
+    def _update_forward_extremities_txn(
+        self, txn, new_forward_extremities, max_stream_order
+    ):
+        for room_id, new_extrem in new_forward_extremities.items():
+            self.db_pool.simple_delete_txn(
+                txn, table="event_forward_extremities", keyvalues={"room_id": room_id}
+            )
+            txn.call_after(
+                self.store.get_latest_event_ids_in_room.invalidate, (room_id,)
+            )
+
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="event_forward_extremities",
+            values=[
+                {"event_id": ev_id, "room_id": room_id}
+                for room_id, new_extrem in new_forward_extremities.items()
+                for ev_id in new_extrem
+            ],
+        )
+        # We now insert into stream_ordering_to_exterm a mapping from room_id,
+        # new stream_ordering to new forward extremeties in the room.
+        # This allows us to later efficiently look up the forward extremeties
+        # for a room before a given stream_ordering
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="stream_ordering_to_exterm",
+            values=[
+                {
+                    "room_id": room_id,
+                    "event_id": event_id,
+                    "stream_ordering": max_stream_order,
+                }
+                for room_id, new_extrem in new_forward_extremities.items()
+                for event_id in new_extrem
+            ],
+        )
+
+    @classmethod
+    def _filter_events_and_contexts_for_duplicates(cls, events_and_contexts):
+        """Ensure that we don't have the same event twice.
+
+        Pick the earliest non-outlier if there is one, else the earliest one.
+
+        Args:
+            events_and_contexts (list[(EventBase, EventContext)]):
+        Returns:
+            list[(EventBase, EventContext)]: filtered list
+        """
+        new_events_and_contexts = OrderedDict()
+        for event, context in events_and_contexts:
+            prev_event_context = new_events_and_contexts.get(event.event_id)
+            if prev_event_context:
+                if not event.internal_metadata.is_outlier():
+                    if prev_event_context[0].internal_metadata.is_outlier():
+                        # To ensure correct ordering we pop, as OrderedDict is
+                        # ordered by first insertion.
+                        new_events_and_contexts.pop(event.event_id, None)
+                        new_events_and_contexts[event.event_id] = (event, context)
+            else:
+                new_events_and_contexts[event.event_id] = (event, context)
+        return list(new_events_and_contexts.values())
+
+    def _update_room_depths_txn(self, txn, events_and_contexts, backfilled):
+        """Update min_depth for each room
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            events_and_contexts (list[(EventBase, EventContext)]): events
+                we are persisting
+            backfilled (bool): True if the events were backfilled
+        """
+        depth_updates = {}
+        for event, context in events_and_contexts:
+            # Remove the any existing cache entries for the event_ids
+            txn.call_after(self.store._invalidate_get_event_cache, event.event_id)
+            if not backfilled:
+                txn.call_after(
+                    self.store._events_stream_cache.entity_has_changed,
+                    event.room_id,
+                    event.internal_metadata.stream_ordering,
+                )
+
+            if not event.internal_metadata.is_outlier() and not context.rejected:
+                depth_updates[event.room_id] = max(
+                    event.depth, depth_updates.get(event.room_id, event.depth)
+                )
+
+        for room_id, depth in depth_updates.items():
+            self._update_min_depth_for_room_txn(txn, room_id, depth)
+
+    def _update_outliers_txn(self, txn, events_and_contexts):
+        """Update any outliers with new event info.
+
+        This turns outliers into ex-outliers (unless the new event was
+        rejected).
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            events_and_contexts (list[(EventBase, EventContext)]): events
+                we are persisting
+
+        Returns:
+            list[(EventBase, EventContext)] new list, without events which
+            are already in the events table.
+        """
+        txn.execute(
+            "SELECT event_id, outlier FROM events WHERE event_id in (%s)"
+            % (",".join(["?"] * len(events_and_contexts)),),
+            [event.event_id for event, _ in events_and_contexts],
+        )
+
+        have_persisted = {event_id: outlier for event_id, outlier in txn}
+
+        to_remove = set()
+        for event, context in events_and_contexts:
+            if event.event_id not in have_persisted:
+                continue
+
+            to_remove.add(event)
+
+            if context.rejected:
+                # If the event is rejected then we don't care if the event
+                # was an outlier or not.
+                continue
+
+            outlier_persisted = have_persisted[event.event_id]
+            if not event.internal_metadata.is_outlier() and outlier_persisted:
+                # We received a copy of an event that we had already stored as
+                # an outlier in the database. We now have some state at that
+                # so we need to update the state_groups table with that state.
+
+                # insert into event_to_state_groups.
+                try:
+                    self._store_event_state_mappings_txn(txn, ((event, context),))
+                except Exception:
+                    logger.exception("")
+                    raise
+
+                metadata_json = encode_json(event.internal_metadata.get_dict())
+
+                sql = "UPDATE event_json SET internal_metadata = ? WHERE event_id = ?"
+                txn.execute(sql, (metadata_json, event.event_id))
+
+                # Add an entry to the ex_outlier_stream table to replicate the
+                # change in outlier status to our workers.
+                stream_order = event.internal_metadata.stream_ordering
+                state_group_id = context.state_group
+                self.db_pool.simple_insert_txn(
+                    txn,
+                    table="ex_outlier_stream",
+                    values={
+                        "event_stream_ordering": stream_order,
+                        "event_id": event.event_id,
+                        "state_group": state_group_id,
+                    },
+                )
+
+                sql = "UPDATE events SET outlier = ? WHERE event_id = ?"
+                txn.execute(sql, (False, event.event_id))
+
+                # Update the event_backward_extremities table now that this
+                # event isn't an outlier any more.
+                self._update_backward_extremeties(txn, [event])
+
+        return [ec for ec in events_and_contexts if ec[0] not in to_remove]
+
+    def _store_event_txn(self, txn, events_and_contexts):
+        """Insert new events into the event and event_json tables
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            events_and_contexts (list[(EventBase, EventContext)]): events
+                we are persisting
+        """
+
+        if not events_and_contexts:
+            # nothing to do here
+            return
+
+        def event_dict(event):
+            d = event.get_dict()
+            d.pop("redacted", None)
+            d.pop("redacted_because", None)
+            return d
+
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="event_json",
+            values=[
+                {
+                    "event_id": event.event_id,
+                    "room_id": event.room_id,
+                    "internal_metadata": encode_json(
+                        event.internal_metadata.get_dict()
+                    ),
+                    "json": encode_json(event_dict(event)),
+                    "format_version": event.format_version,
+                }
+                for event, _ in events_and_contexts
+            ],
+        )
+
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="events",
+            values=[
+                {
+                    "stream_ordering": event.internal_metadata.stream_ordering,
+                    "topological_ordering": event.depth,
+                    "depth": event.depth,
+                    "event_id": event.event_id,
+                    "room_id": event.room_id,
+                    "type": event.type,
+                    "processed": True,
+                    "outlier": event.internal_metadata.is_outlier(),
+                    "origin_server_ts": int(event.origin_server_ts),
+                    "received_ts": self._clock.time_msec(),
+                    "sender": event.sender,
+                    "contains_url": (
+                        "url" in event.content and isinstance(event.content["url"], str)
+                    ),
+                    "count_as_unread": should_count_as_unread(event, context),
+                }
+                for event, context in events_and_contexts
+            ],
+        )
+
+        for event, _ in events_and_contexts:
+            if not event.internal_metadata.is_redacted():
+                # If we're persisting an unredacted event we go and ensure
+                # that we mark any redactions that reference this event as
+                # requiring censoring.
+                self.db_pool.simple_update_txn(
+                    txn,
+                    table="redactions",
+                    keyvalues={"redacts": event.event_id},
+                    updatevalues={"have_censored": False},
+                )
+
+    def _store_rejected_events_txn(self, txn, events_and_contexts):
+        """Add rows to the 'rejections' table for received events which were
+        rejected
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            events_and_contexts (list[(EventBase, EventContext)]): events
+                we are persisting
+
+        Returns:
+            list[(EventBase, EventContext)] new list, without the rejected
+                events.
+        """
+        # Remove the rejected events from the list now that we've added them
+        # to the events table and the events_json table.
+        to_remove = set()
+        for event, context in events_and_contexts:
+            if context.rejected:
+                # Insert the event_id into the rejections table
+                self._store_rejections_txn(txn, event.event_id, context.rejected)
+                to_remove.add(event)
+
+        return [ec for ec in events_and_contexts if ec[0] not in to_remove]
+
+    def _update_metadata_tables_txn(
+        self, txn, events_and_contexts, all_events_and_contexts, backfilled
+    ):
+        """Update all the miscellaneous tables for new events
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection): db connection
+            events_and_contexts (list[(EventBase, EventContext)]): events
+                we are persisting
+            all_events_and_contexts (list[(EventBase, EventContext)]): all
+                events that we were going to persist. This includes events
+                we've already persisted, etc, that wouldn't appear in
+                events_and_context.
+            backfilled (bool): True if the events were backfilled
+        """
+
+        # Insert all the push actions into the event_push_actions table.
+        self._set_push_actions_for_event_and_users_txn(
+            txn,
+            events_and_contexts=events_and_contexts,
+            all_events_and_contexts=all_events_and_contexts,
+        )
+
+        if not events_and_contexts:
+            # nothing to do here
+            return
+
+        for event, context in events_and_contexts:
+            if event.type == EventTypes.Redaction and event.redacts is not None:
+                # Remove the entries in the event_push_actions table for the
+                # redacted event.
+                self._remove_push_actions_for_event_id_txn(
+                    txn, event.room_id, event.redacts
+                )
+
+                # Remove from relations table.
+                self._handle_redaction(txn, event.redacts)
+
+        # Update the event_forward_extremities, event_backward_extremities and
+        # event_edges tables.
+        self._handle_mult_prev_events(
+            txn, events=[event for event, _ in events_and_contexts]
+        )
+
+        for event, _ in events_and_contexts:
+            if event.type == EventTypes.Name:
+                # Insert into the event_search table.
+                self._store_room_name_txn(txn, event)
+            elif event.type == EventTypes.Topic:
+                # Insert into the event_search table.
+                self._store_room_topic_txn(txn, event)
+            elif event.type == EventTypes.Message:
+                # Insert into the event_search table.
+                self._store_room_message_txn(txn, event)
+            elif event.type == EventTypes.Redaction and event.redacts is not None:
+                # Insert into the redactions table.
+                self._store_redaction(txn, event)
+            elif event.type == EventTypes.Retention:
+                # Update the room_retention table.
+                self._store_retention_policy_for_room_txn(txn, event)
+
+            self._handle_event_relations(txn, event)
+
+            # Store the labels for this event.
+            labels = event.content.get(EventContentFields.LABELS)
+            if labels:
+                self.insert_labels_for_event_txn(
+                    txn, event.event_id, labels, event.room_id, event.depth
+                )
+
+            if self._ephemeral_messages_enabled:
+                # If there's an expiry timestamp on the event, store it.
+                expiry_ts = event.content.get(EventContentFields.SELF_DESTRUCT_AFTER)
+                if isinstance(expiry_ts, int) and not event.is_state():
+                    self._insert_event_expiry_txn(txn, event.event_id, expiry_ts)
+
+        # Insert into the room_memberships table.
+        self._store_room_members_txn(
+            txn,
+            [
+                event
+                for event, _ in events_and_contexts
+                if event.type == EventTypes.Member
+            ],
+            backfilled=backfilled,
+        )
+
+        # Insert event_reference_hashes table.
+        self._store_event_reference_hashes_txn(
+            txn, [event for event, _ in events_and_contexts]
+        )
+
+        state_events_and_contexts = [
+            ec for ec in events_and_contexts if ec[0].is_state()
+        ]
+
+        state_values = []
+        for event, context in state_events_and_contexts:
+            vals = {
+                "event_id": event.event_id,
+                "room_id": event.room_id,
+                "type": event.type,
+                "state_key": event.state_key,
+            }
+
+            # TODO: How does this work with backfilling?
+            if hasattr(event, "replaces_state"):
+                vals["prev_state"] = event.replaces_state
+
+            state_values.append(vals)
+
+        self.db_pool.simple_insert_many_txn(
+            txn, table="state_events", values=state_values
+        )
+
+        # Prefill the event cache
+        self._add_to_cache(txn, events_and_contexts)
+
+    def _add_to_cache(self, txn, events_and_contexts):
+        to_prefill = []
+
+        rows = []
+        N = 200
+        for i in range(0, len(events_and_contexts), N):
+            ev_map = {e[0].event_id: e[0] for e in events_and_contexts[i : i + N]}
+            if not ev_map:
+                break
+
+            sql = (
+                "SELECT "
+                " e.event_id as event_id, "
+                " r.redacts as redacts,"
+                " rej.event_id as rejects "
+                " FROM events as e"
+                " LEFT JOIN rejections as rej USING (event_id)"
+                " LEFT JOIN redactions as r ON e.event_id = r.redacts"
+                " WHERE "
+            )
+
+            clause, args = make_in_list_sql_clause(
+                self.database_engine, "e.event_id", list(ev_map)
+            )
+
+            txn.execute(sql + clause, args)
+            rows = self.db_pool.cursor_to_dict(txn)
+            for row in rows:
+                event = ev_map[row["event_id"]]
+                if not row["rejects"] and not row["redacts"]:
+                    to_prefill.append(
+                        _EventCacheEntry(event=event, redacted_event=None)
+                    )
+
+        def prefill():
+            for cache_entry in to_prefill:
+                self.store._get_event_cache.prefill(
+                    (cache_entry[0].event_id,), cache_entry
+                )
+
+        txn.call_after(prefill)
+
+    def _store_redaction(self, txn, event):
+        # invalidate the cache for the redacted event
+        txn.call_after(self.store._invalidate_get_event_cache, event.redacts)
+
+        self.db_pool.simple_insert_txn(
+            txn,
+            table="redactions",
+            values={
+                "event_id": event.event_id,
+                "redacts": event.redacts,
+                "received_ts": self._clock.time_msec(),
+            },
+        )
+
+    def insert_labels_for_event_txn(
+        self, txn, event_id, labels, room_id, topological_ordering
+    ):
+        """Store the mapping between an event's ID and its labels, with one row per
+        (event_id, label) tuple.
+
+        Args:
+            txn (LoggingTransaction): The transaction to execute.
+            event_id (str): The event's ID.
+            labels (list[str]): A list of text labels.
+            room_id (str): The ID of the room the event was sent to.
+            topological_ordering (int): The position of the event in the room's topology.
+        """
+        return self.db_pool.simple_insert_many_txn(
+            txn=txn,
+            table="event_labels",
+            values=[
+                {
+                    "event_id": event_id,
+                    "label": label,
+                    "room_id": room_id,
+                    "topological_ordering": topological_ordering,
+                }
+                for label in labels
+            ],
+        )
+
+    def _insert_event_expiry_txn(self, txn, event_id, expiry_ts):
+        """Save the expiry timestamp associated with a given event ID.
+
+        Args:
+            txn (LoggingTransaction): The database transaction to use.
+            event_id (str): The event ID the expiry timestamp is associated with.
+            expiry_ts (int): The timestamp at which to expire (delete) the event.
+        """
+        return self.db_pool.simple_insert_txn(
+            txn=txn,
+            table="event_expiry",
+            values={"event_id": event_id, "expiry_ts": expiry_ts},
+        )
+
+    def _store_event_reference_hashes_txn(self, txn, events):
+        """Store a hash for a PDU
+        Args:
+            txn (cursor):
+            events (list): list of Events.
+        """
+
+        vals = []
+        for event in events:
+            ref_alg, ref_hash_bytes = compute_event_reference_hash(event)
+            vals.append(
+                {
+                    "event_id": event.event_id,
+                    "algorithm": ref_alg,
+                    "hash": memoryview(ref_hash_bytes),
+                }
+            )
+
+        self.db_pool.simple_insert_many_txn(
+            txn, table="event_reference_hashes", values=vals
+        )
+
+    def _store_room_members_txn(self, txn, events, backfilled):
+        """Store a room member in the database.
+        """
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="room_memberships",
+            values=[
+                {
+                    "event_id": event.event_id,
+                    "user_id": event.state_key,
+                    "sender": event.user_id,
+                    "room_id": event.room_id,
+                    "membership": event.membership,
+                    "display_name": event.content.get("displayname", None),
+                    "avatar_url": event.content.get("avatar_url", None),
+                }
+                for event in events
+            ],
+        )
+
+        for event in events:
+            txn.call_after(
+                self.store._membership_stream_cache.entity_has_changed,
+                event.state_key,
+                event.internal_metadata.stream_ordering,
+            )
+            txn.call_after(
+                self.store.get_invited_rooms_for_local_user.invalidate,
+                (event.state_key,),
+            )
+
+            # We update the local_current_membership table only if the event is
+            # "current", i.e., its something that has just happened.
+            #
+            # This will usually get updated by the `current_state_events` handling,
+            # unless its an outlier, and an outlier is only "current" if it's an "out of
+            # band membership", like a remote invite or a rejection of a remote invite.
+            if (
+                self.is_mine_id(event.state_key)
+                and not backfilled
+                and event.internal_metadata.is_outlier()
+                and event.internal_metadata.is_out_of_band_membership()
+            ):
+                self.db_pool.simple_upsert_txn(
+                    txn,
+                    table="local_current_membership",
+                    keyvalues={"room_id": event.room_id, "user_id": event.state_key},
+                    values={
+                        "event_id": event.event_id,
+                        "membership": event.membership,
+                    },
+                )
+
+    def _handle_event_relations(self, txn, event):
+        """Handles inserting relation data during peristence of events
+
+        Args:
+            txn
+            event (EventBase)
+        """
+        relation = event.content.get("m.relates_to")
+        if not relation:
+            # No relations
+            return
+
+        rel_type = relation.get("rel_type")
+        if rel_type not in (
+            RelationTypes.ANNOTATION,
+            RelationTypes.REFERENCE,
+            RelationTypes.REPLACE,
+        ):
+            # Unknown relation type
+            return
+
+        parent_id = relation.get("event_id")
+        if not parent_id:
+            # Invalid relation
+            return
+
+        aggregation_key = relation.get("key")
+
+        self.db_pool.simple_insert_txn(
+            txn,
+            table="event_relations",
+            values={
+                "event_id": event.event_id,
+                "relates_to_id": parent_id,
+                "relation_type": rel_type,
+                "aggregation_key": aggregation_key,
+            },
+        )
+
+        txn.call_after(self.store.get_relations_for_event.invalidate_many, (parent_id,))
+        txn.call_after(
+            self.store.get_aggregation_groups_for_event.invalidate_many, (parent_id,)
+        )
+
+        if rel_type == RelationTypes.REPLACE:
+            txn.call_after(self.store.get_applicable_edit.invalidate, (parent_id,))
+
+    def _handle_redaction(self, txn, redacted_event_id):
+        """Handles receiving a redaction and checking whether we need to remove
+        any redacted relations from the database.
+
+        Args:
+            txn
+            redacted_event_id (str): The event that was redacted.
+        """
+
+        self.db_pool.simple_delete_txn(
+            txn, table="event_relations", keyvalues={"event_id": redacted_event_id}
+        )
+
+    def _store_room_topic_txn(self, txn, event):
+        if hasattr(event, "content") and "topic" in event.content:
+            self.store_event_search_txn(
+                txn, event, "content.topic", event.content["topic"]
+            )
+
+    def _store_room_name_txn(self, txn, event):
+        if hasattr(event, "content") and "name" in event.content:
+            self.store_event_search_txn(
+                txn, event, "content.name", event.content["name"]
+            )
+
+    def _store_room_message_txn(self, txn, event):
+        if hasattr(event, "content") and "body" in event.content:
+            self.store_event_search_txn(
+                txn, event, "content.body", event.content["body"]
+            )
+
+    def _store_retention_policy_for_room_txn(self, txn, event):
+        if hasattr(event, "content") and (
+            "min_lifetime" in event.content or "max_lifetime" in event.content
+        ):
+            if (
+                "min_lifetime" in event.content
+                and not isinstance(event.content.get("min_lifetime"), int)
+            ) or (
+                "max_lifetime" in event.content
+                and not isinstance(event.content.get("max_lifetime"), int)
+            ):
+                # Ignore the event if one of the value isn't an integer.
+                return
+
+            self.db_pool.simple_insert_txn(
+                txn=txn,
+                table="room_retention",
+                values={
+                    "room_id": event.room_id,
+                    "event_id": event.event_id,
+                    "min_lifetime": event.content.get("min_lifetime"),
+                    "max_lifetime": event.content.get("max_lifetime"),
+                },
+            )
+
+            self.store._invalidate_cache_and_stream(
+                txn, self.store.get_retention_policy_for_room, (event.room_id,)
+            )
+
+    def store_event_search_txn(self, txn, event, key, value):
+        """Add event to the search table
+
+        Args:
+            txn (cursor):
+            event (EventBase):
+            key (str):
+            value (str):
+        """
+        self.store.store_search_entries_txn(
+            txn,
+            (
+                SearchEntry(
+                    key=key,
+                    value=value,
+                    event_id=event.event_id,
+                    room_id=event.room_id,
+                    stream_ordering=event.internal_metadata.stream_ordering,
+                    origin_server_ts=event.origin_server_ts,
+                ),
+            ),
+        )
+
+    def _set_push_actions_for_event_and_users_txn(
+        self, txn, events_and_contexts, all_events_and_contexts
+    ):
+        """Handles moving push actions from staging table to main
+        event_push_actions table for all events in `events_and_contexts`.
+
+        Also ensures that all events in `all_events_and_contexts` are removed
+        from the push action staging area.
+
+        Args:
+            events_and_contexts (list[(EventBase, EventContext)]): events
+                we are persisting
+            all_events_and_contexts (list[(EventBase, EventContext)]): all
+                events that we were going to persist. This includes events
+                we've already persisted, etc, that wouldn't appear in
+                events_and_context.
+        """
+
+        sql = """
+            INSERT INTO event_push_actions (
+                room_id, event_id, user_id, actions, stream_ordering,
+                topological_ordering, notif, highlight
+            )
+            SELECT ?, event_id, user_id, actions, ?, ?, notif, highlight
+            FROM event_push_actions_staging
+            WHERE event_id = ?
+        """
+
+        if events_and_contexts:
+            txn.executemany(
+                sql,
+                (
+                    (
+                        event.room_id,
+                        event.internal_metadata.stream_ordering,
+                        event.depth,
+                        event.event_id,
+                    )
+                    for event, _ in events_and_contexts
+                ),
+            )
+
+        for event, _ in events_and_contexts:
+            user_ids = self.db_pool.simple_select_onecol_txn(
+                txn,
+                table="event_push_actions_staging",
+                keyvalues={"event_id": event.event_id},
+                retcol="user_id",
+            )
+
+            for uid in user_ids:
+                txn.call_after(
+                    self.store.get_unread_event_push_actions_by_room_for_user.invalidate_many,
+                    (event.room_id, uid),
+                )
+
+        # Now we delete the staging area for *all* events that were being
+        # persisted.
+        txn.executemany(
+            "DELETE FROM event_push_actions_staging WHERE event_id = ?",
+            ((event.event_id,) for event, _ in all_events_and_contexts),
+        )
+
+    def _remove_push_actions_for_event_id_txn(self, txn, room_id, event_id):
+        # Sad that we have to blow away the cache for the whole room here
+        txn.call_after(
+            self.store.get_unread_event_push_actions_by_room_for_user.invalidate_many,
+            (room_id,),
+        )
+        txn.execute(
+            "DELETE FROM event_push_actions WHERE room_id = ? AND event_id = ?",
+            (room_id, event_id),
+        )
+
+    def _store_rejections_txn(self, txn, event_id, reason):
+        self.db_pool.simple_insert_txn(
+            txn,
+            table="rejections",
+            values={
+                "event_id": event_id,
+                "reason": reason,
+                "last_check": self._clock.time_msec(),
+            },
+        )
+
+    def _store_event_state_mappings_txn(
+        self, txn, events_and_contexts: Iterable[Tuple[EventBase, EventContext]]
+    ):
+        state_groups = {}
+        for event, context in events_and_contexts:
+            if event.internal_metadata.is_outlier():
+                continue
+
+            # if the event was rejected, just give it the same state as its
+            # predecessor.
+            if context.rejected:
+                state_groups[event.event_id] = context.state_group_before_event
+                continue
+
+            state_groups[event.event_id] = context.state_group
+
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="event_to_state_groups",
+            values=[
+                {"state_group": state_group_id, "event_id": event_id}
+                for event_id, state_group_id in state_groups.items()
+            ],
+        )
+
+        for event_id, state_group_id in state_groups.items():
+            txn.call_after(
+                self.store._get_state_group_for_event.prefill,
+                (event_id,),
+                state_group_id,
+            )
+
+    def _update_min_depth_for_room_txn(self, txn, room_id, depth):
+        min_depth = self.store._get_min_depth_interaction(txn, room_id)
+
+        if min_depth is not None and depth >= min_depth:
+            return
+
+        self.db_pool.simple_upsert_txn(
+            txn,
+            table="room_depth",
+            keyvalues={"room_id": room_id},
+            values={"min_depth": depth},
+        )
+
+    def _handle_mult_prev_events(self, txn, events):
+        """
+        For the given event, update the event edges table and forward and
+        backward extremities tables.
+        """
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="event_edges",
+            values=[
+                {
+                    "event_id": ev.event_id,
+                    "prev_event_id": e_id,
+                    "room_id": ev.room_id,
+                    "is_state": False,
+                }
+                for ev in events
+                for e_id in ev.prev_event_ids()
+            ],
+        )
+
+        self._update_backward_extremeties(txn, events)
+
+    def _update_backward_extremeties(self, txn, events):
+        """Updates the event_backward_extremities tables based on the new/updated
+        events being persisted.
+
+        This is called for new events *and* for events that were outliers, but
+        are now being persisted as non-outliers.
+
+        Forward extremities are handled when we first start persisting the events.
+        """
+        events_by_room = {}
+        for ev in events:
+            events_by_room.setdefault(ev.room_id, []).append(ev)
+
+        query = (
+            "INSERT INTO event_backward_extremities (event_id, room_id)"
+            " SELECT ?, ? WHERE NOT EXISTS ("
+            " SELECT 1 FROM event_backward_extremities"
+            " WHERE event_id = ? AND room_id = ?"
+            " )"
+            " AND NOT EXISTS ("
+            " SELECT 1 FROM events WHERE event_id = ? AND room_id = ? "
+            " AND outlier = ?"
+            " )"
+        )
+
+        txn.executemany(
+            query,
+            [
+                (e_id, ev.room_id, e_id, ev.room_id, e_id, ev.room_id, False)
+                for ev in events
+                for e_id in ev.prev_event_ids()
+                if not ev.internal_metadata.is_outlier()
+            ],
+        )
+
+        query = (
+            "DELETE FROM event_backward_extremities"
+            " WHERE event_id = ? AND room_id = ?"
+        )
+        txn.executemany(
+            query,
+            [
+                (ev.event_id, ev.room_id)
+                for ev in events
+                if not ev.internal_metadata.is_outlier()
+            ],
+        )
diff --git a/synapse/storage/databases/main/events_bg_updates.py b/synapse/storage/databases/main/events_bg_updates.py
new file mode 100644
index 0000000000..35a0e09e3c
--- /dev/null
+++ b/synapse/storage/databases/main/events_bg_updates.py
@@ -0,0 +1,585 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from twisted.internet import defer
+
+from synapse.api.constants import EventContentFields
+from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
+from synapse.storage.database import DatabasePool
+
+logger = logging.getLogger(__name__)
+
+
+class EventsBackgroundUpdatesStore(SQLBaseStore):
+
+    EVENT_ORIGIN_SERVER_TS_NAME = "event_origin_server_ts"
+    EVENT_FIELDS_SENDER_URL_UPDATE_NAME = "event_fields_sender_url"
+    DELETE_SOFT_FAILED_EXTREMITIES = "delete_soft_failed_extremities"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(EventsBackgroundUpdatesStore, self).__init__(database, db_conn, hs)
+
+        self.db_pool.updates.register_background_update_handler(
+            self.EVENT_ORIGIN_SERVER_TS_NAME, self._background_reindex_origin_server_ts
+        )
+        self.db_pool.updates.register_background_update_handler(
+            self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME,
+            self._background_reindex_fields_sender,
+        )
+
+        self.db_pool.updates.register_background_index_update(
+            "event_contains_url_index",
+            index_name="event_contains_url_index",
+            table="events",
+            columns=["room_id", "topological_ordering", "stream_ordering"],
+            where_clause="contains_url = true AND outlier = false",
+        )
+
+        # an event_id index on event_search is useful for the purge_history
+        # api. Plus it means we get to enforce some integrity with a UNIQUE
+        # clause
+        self.db_pool.updates.register_background_index_update(
+            "event_search_event_id_idx",
+            index_name="event_search_event_id_idx",
+            table="event_search",
+            columns=["event_id"],
+            unique=True,
+            psql_only=True,
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            self.DELETE_SOFT_FAILED_EXTREMITIES, self._cleanup_extremities_bg_update
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            "redactions_received_ts", self._redactions_received_ts
+        )
+
+        # This index gets deleted in `event_fix_redactions_bytes` update
+        self.db_pool.updates.register_background_index_update(
+            "event_fix_redactions_bytes_create_index",
+            index_name="redactions_censored_redacts",
+            table="redactions",
+            columns=["redacts"],
+            where_clause="have_censored",
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            "event_fix_redactions_bytes", self._event_fix_redactions_bytes
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            "event_store_labels", self._event_store_labels
+        )
+
+        self.db_pool.updates.register_background_index_update(
+            "redactions_have_censored_ts_idx",
+            index_name="redactions_have_censored_ts",
+            table="redactions",
+            columns=["received_ts"],
+            where_clause="NOT have_censored",
+        )
+
+    @defer.inlineCallbacks
+    def _background_reindex_fields_sender(self, progress, batch_size):
+        target_min_stream_id = progress["target_min_stream_id_inclusive"]
+        max_stream_id = progress["max_stream_id_exclusive"]
+        rows_inserted = progress.get("rows_inserted", 0)
+
+        INSERT_CLUMP_SIZE = 1000
+
+        def reindex_txn(txn):
+            sql = (
+                "SELECT stream_ordering, event_id, json FROM events"
+                " INNER JOIN event_json USING (event_id)"
+                " WHERE ? <= stream_ordering AND stream_ordering < ?"
+                " ORDER BY stream_ordering DESC"
+                " LIMIT ?"
+            )
+
+            txn.execute(sql, (target_min_stream_id, max_stream_id, batch_size))
+
+            rows = txn.fetchall()
+            if not rows:
+                return 0
+
+            min_stream_id = rows[-1][0]
+
+            update_rows = []
+            for row in rows:
+                try:
+                    event_id = row[1]
+                    event_json = db_to_json(row[2])
+                    sender = event_json["sender"]
+                    content = event_json["content"]
+
+                    contains_url = "url" in content
+                    if contains_url:
+                        contains_url &= isinstance(content["url"], str)
+                except (KeyError, AttributeError):
+                    # If the event is missing a necessary field then
+                    # skip over it.
+                    continue
+
+                update_rows.append((sender, contains_url, event_id))
+
+            sql = "UPDATE events SET sender = ?, contains_url = ? WHERE event_id = ?"
+
+            for index in range(0, len(update_rows), INSERT_CLUMP_SIZE):
+                clump = update_rows[index : index + INSERT_CLUMP_SIZE]
+                txn.executemany(sql, clump)
+
+            progress = {
+                "target_min_stream_id_inclusive": target_min_stream_id,
+                "max_stream_id_exclusive": min_stream_id,
+                "rows_inserted": rows_inserted + len(rows),
+            }
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME, progress
+            )
+
+            return len(rows)
+
+        result = yield self.db_pool.runInteraction(
+            self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME, reindex_txn
+        )
+
+        if not result:
+            yield self.db_pool.updates._end_background_update(
+                self.EVENT_FIELDS_SENDER_URL_UPDATE_NAME
+            )
+
+        return result
+
+    @defer.inlineCallbacks
+    def _background_reindex_origin_server_ts(self, progress, batch_size):
+        target_min_stream_id = progress["target_min_stream_id_inclusive"]
+        max_stream_id = progress["max_stream_id_exclusive"]
+        rows_inserted = progress.get("rows_inserted", 0)
+
+        INSERT_CLUMP_SIZE = 1000
+
+        def reindex_search_txn(txn):
+            sql = (
+                "SELECT stream_ordering, event_id FROM events"
+                " WHERE ? <= stream_ordering AND stream_ordering < ?"
+                " ORDER BY stream_ordering DESC"
+                " LIMIT ?"
+            )
+
+            txn.execute(sql, (target_min_stream_id, max_stream_id, batch_size))
+
+            rows = txn.fetchall()
+            if not rows:
+                return 0
+
+            min_stream_id = rows[-1][0]
+            event_ids = [row[1] for row in rows]
+
+            rows_to_update = []
+
+            chunks = [event_ids[i : i + 100] for i in range(0, len(event_ids), 100)]
+            for chunk in chunks:
+                ev_rows = self.db_pool.simple_select_many_txn(
+                    txn,
+                    table="event_json",
+                    column="event_id",
+                    iterable=chunk,
+                    retcols=["event_id", "json"],
+                    keyvalues={},
+                )
+
+                for row in ev_rows:
+                    event_id = row["event_id"]
+                    event_json = db_to_json(row["json"])
+                    try:
+                        origin_server_ts = event_json["origin_server_ts"]
+                    except (KeyError, AttributeError):
+                        # If the event is missing a necessary field then
+                        # skip over it.
+                        continue
+
+                    rows_to_update.append((origin_server_ts, event_id))
+
+            sql = "UPDATE events SET origin_server_ts = ? WHERE event_id = ?"
+
+            for index in range(0, len(rows_to_update), INSERT_CLUMP_SIZE):
+                clump = rows_to_update[index : index + INSERT_CLUMP_SIZE]
+                txn.executemany(sql, clump)
+
+            progress = {
+                "target_min_stream_id_inclusive": target_min_stream_id,
+                "max_stream_id_exclusive": min_stream_id,
+                "rows_inserted": rows_inserted + len(rows_to_update),
+            }
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, self.EVENT_ORIGIN_SERVER_TS_NAME, progress
+            )
+
+            return len(rows_to_update)
+
+        result = yield self.db_pool.runInteraction(
+            self.EVENT_ORIGIN_SERVER_TS_NAME, reindex_search_txn
+        )
+
+        if not result:
+            yield self.db_pool.updates._end_background_update(
+                self.EVENT_ORIGIN_SERVER_TS_NAME
+            )
+
+        return result
+
+    @defer.inlineCallbacks
+    def _cleanup_extremities_bg_update(self, progress, batch_size):
+        """Background update to clean out extremities that should have been
+        deleted previously.
+
+        Mainly used to deal with the aftermath of #5269.
+        """
+
+        # This works by first copying all existing forward extremities into the
+        # `_extremities_to_check` table at start up, and then checking each
+        # event in that table whether we have any descendants that are not
+        # soft-failed/rejected. If that is the case then we delete that event
+        # from the forward extremities table.
+        #
+        # For efficiency, we do this in batches by recursively pulling out all
+        # descendants of a batch until we find the non soft-failed/rejected
+        # events, i.e. the set of descendants whose chain of prev events back
+        # to the batch of extremities are all soft-failed or rejected.
+        # Typically, we won't find any such events as extremities will rarely
+        # have any descendants, but if they do then we should delete those
+        # extremities.
+
+        def _cleanup_extremities_bg_update_txn(txn):
+            # The set of extremity event IDs that we're checking this round
+            original_set = set()
+
+            # A dict[str, set[str]] of event ID to their prev events.
+            graph = {}
+
+            # The set of descendants of the original set that are not rejected
+            # nor soft-failed. Ancestors of these events should be removed
+            # from the forward extremities table.
+            non_rejected_leaves = set()
+
+            # Set of event IDs that have been soft failed, and for which we
+            # should check if they have descendants which haven't been soft
+            # failed.
+            soft_failed_events_to_lookup = set()
+
+            # First, we get `batch_size` events from the table, pulling out
+            # their successor events, if any, and the successor events'
+            # rejection status.
+            txn.execute(
+                """SELECT prev_event_id, event_id, internal_metadata,
+                    rejections.event_id IS NOT NULL, events.outlier
+                FROM (
+                    SELECT event_id AS prev_event_id
+                    FROM _extremities_to_check
+                    LIMIT ?
+                ) AS f
+                LEFT JOIN event_edges USING (prev_event_id)
+                LEFT JOIN events USING (event_id)
+                LEFT JOIN event_json USING (event_id)
+                LEFT JOIN rejections USING (event_id)
+                """,
+                (batch_size,),
+            )
+
+            for prev_event_id, event_id, metadata, rejected, outlier in txn:
+                original_set.add(prev_event_id)
+
+                if not event_id or outlier:
+                    # Common case where the forward extremity doesn't have any
+                    # descendants.
+                    continue
+
+                graph.setdefault(event_id, set()).add(prev_event_id)
+
+                soft_failed = False
+                if metadata:
+                    soft_failed = db_to_json(metadata).get("soft_failed")
+
+                if soft_failed or rejected:
+                    soft_failed_events_to_lookup.add(event_id)
+                else:
+                    non_rejected_leaves.add(event_id)
+
+            # Now we recursively check all the soft-failed descendants we
+            # found above in the same way, until we have nothing left to
+            # check.
+            while soft_failed_events_to_lookup:
+                # We only want to do 100 at a time, so we split given list
+                # into two.
+                batch = list(soft_failed_events_to_lookup)
+                to_check, to_defer = batch[:100], batch[100:]
+                soft_failed_events_to_lookup = set(to_defer)
+
+                sql = """SELECT prev_event_id, event_id, internal_metadata,
+                    rejections.event_id IS NOT NULL
+                    FROM event_edges
+                    INNER JOIN events USING (event_id)
+                    INNER JOIN event_json USING (event_id)
+                    LEFT JOIN rejections USING (event_id)
+                    WHERE
+                        NOT events.outlier
+                        AND
+                """
+                clause, args = make_in_list_sql_clause(
+                    self.database_engine, "prev_event_id", to_check
+                )
+                txn.execute(sql + clause, list(args))
+
+                for prev_event_id, event_id, metadata, rejected in txn:
+                    if event_id in graph:
+                        # Already handled this event previously, but we still
+                        # want to record the edge.
+                        graph[event_id].add(prev_event_id)
+                        continue
+
+                    graph[event_id] = {prev_event_id}
+
+                    soft_failed = db_to_json(metadata).get("soft_failed")
+                    if soft_failed or rejected:
+                        soft_failed_events_to_lookup.add(event_id)
+                    else:
+                        non_rejected_leaves.add(event_id)
+
+            # We have a set of non-soft-failed descendants, so we recurse up
+            # the graph to find all ancestors and add them to the set of event
+            # IDs that we can delete from forward extremities table.
+            to_delete = set()
+            while non_rejected_leaves:
+                event_id = non_rejected_leaves.pop()
+                prev_event_ids = graph.get(event_id, set())
+                non_rejected_leaves.update(prev_event_ids)
+                to_delete.update(prev_event_ids)
+
+            to_delete.intersection_update(original_set)
+
+            deleted = self.db_pool.simple_delete_many_txn(
+                txn=txn,
+                table="event_forward_extremities",
+                column="event_id",
+                iterable=to_delete,
+                keyvalues={},
+            )
+
+            logger.info(
+                "Deleted %d forward extremities of %d checked, to clean up #5269",
+                deleted,
+                len(original_set),
+            )
+
+            if deleted:
+                # We now need to invalidate the caches of these rooms
+                rows = self.db_pool.simple_select_many_txn(
+                    txn,
+                    table="events",
+                    column="event_id",
+                    iterable=to_delete,
+                    keyvalues={},
+                    retcols=("room_id",),
+                )
+                room_ids = {row["room_id"] for row in rows}
+                for room_id in room_ids:
+                    txn.call_after(
+                        self.get_latest_event_ids_in_room.invalidate, (room_id,)
+                    )
+
+            self.db_pool.simple_delete_many_txn(
+                txn=txn,
+                table="_extremities_to_check",
+                column="event_id",
+                iterable=original_set,
+                keyvalues={},
+            )
+
+            return len(original_set)
+
+        num_handled = yield self.db_pool.runInteraction(
+            "_cleanup_extremities_bg_update", _cleanup_extremities_bg_update_txn
+        )
+
+        if not num_handled:
+            yield self.db_pool.updates._end_background_update(
+                self.DELETE_SOFT_FAILED_EXTREMITIES
+            )
+
+            def _drop_table_txn(txn):
+                txn.execute("DROP TABLE _extremities_to_check")
+
+            yield self.db_pool.runInteraction(
+                "_cleanup_extremities_bg_update_drop_table", _drop_table_txn
+            )
+
+        return num_handled
+
+    @defer.inlineCallbacks
+    def _redactions_received_ts(self, progress, batch_size):
+        """Handles filling out the `received_ts` column in redactions.
+        """
+        last_event_id = progress.get("last_event_id", "")
+
+        def _redactions_received_ts_txn(txn):
+            # Fetch the set of event IDs that we want to update
+            sql = """
+                SELECT event_id FROM redactions
+                WHERE event_id > ?
+                ORDER BY event_id ASC
+                LIMIT ?
+            """
+
+            txn.execute(sql, (last_event_id, batch_size))
+
+            rows = txn.fetchall()
+            if not rows:
+                return 0
+
+            (upper_event_id,) = rows[-1]
+
+            # Update the redactions with the received_ts.
+            #
+            # Note: Not all events have an associated received_ts, so we
+            # fallback to using origin_server_ts. If we for some reason don't
+            # have an origin_server_ts, lets just use the current timestamp.
+            #
+            # We don't want to leave it null, as then we'll never try and
+            # censor those redactions.
+            sql = """
+                UPDATE redactions
+                SET received_ts = (
+                    SELECT COALESCE(received_ts, origin_server_ts, ?) FROM events
+                    WHERE events.event_id = redactions.event_id
+                )
+                WHERE ? <= event_id AND event_id <= ?
+            """
+
+            txn.execute(sql, (self._clock.time_msec(), last_event_id, upper_event_id))
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, "redactions_received_ts", {"last_event_id": upper_event_id}
+            )
+
+            return len(rows)
+
+        count = yield self.db_pool.runInteraction(
+            "_redactions_received_ts", _redactions_received_ts_txn
+        )
+
+        if not count:
+            yield self.db_pool.updates._end_background_update("redactions_received_ts")
+
+        return count
+
+    @defer.inlineCallbacks
+    def _event_fix_redactions_bytes(self, progress, batch_size):
+        """Undoes hex encoded censored redacted event JSON.
+        """
+
+        def _event_fix_redactions_bytes_txn(txn):
+            # This update is quite fast due to new index.
+            txn.execute(
+                """
+                UPDATE event_json
+                SET
+                    json = convert_from(json::bytea, 'utf8')
+                FROM redactions
+                WHERE
+                    redactions.have_censored
+                    AND event_json.event_id = redactions.redacts
+                    AND json NOT LIKE '{%';
+                """
+            )
+
+            txn.execute("DROP INDEX redactions_censored_redacts")
+
+        yield self.db_pool.runInteraction(
+            "_event_fix_redactions_bytes", _event_fix_redactions_bytes_txn
+        )
+
+        yield self.db_pool.updates._end_background_update("event_fix_redactions_bytes")
+
+        return 1
+
+    @defer.inlineCallbacks
+    def _event_store_labels(self, progress, batch_size):
+        """Background update handler which will store labels for existing events."""
+        last_event_id = progress.get("last_event_id", "")
+
+        def _event_store_labels_txn(txn):
+            txn.execute(
+                """
+                SELECT event_id, json FROM event_json
+                LEFT JOIN event_labels USING (event_id)
+                WHERE event_id > ? AND label IS NULL
+                ORDER BY event_id LIMIT ?
+                """,
+                (last_event_id, batch_size),
+            )
+
+            results = list(txn)
+
+            nbrows = 0
+            last_row_event_id = ""
+            for (event_id, event_json_raw) in results:
+                try:
+                    event_json = db_to_json(event_json_raw)
+
+                    self.db_pool.simple_insert_many_txn(
+                        txn=txn,
+                        table="event_labels",
+                        values=[
+                            {
+                                "event_id": event_id,
+                                "label": label,
+                                "room_id": event_json["room_id"],
+                                "topological_ordering": event_json["depth"],
+                            }
+                            for label in event_json["content"].get(
+                                EventContentFields.LABELS, []
+                            )
+                            if isinstance(label, str)
+                        ],
+                    )
+                except Exception as e:
+                    logger.warning(
+                        "Unable to load event %s (no labels will be imported): %s",
+                        event_id,
+                        e,
+                    )
+
+                nbrows += 1
+                last_row_event_id = event_id
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, "event_store_labels", {"last_event_id": last_row_event_id}
+            )
+
+            return nbrows
+
+        num_rows = yield self.db_pool.runInteraction(
+            desc="event_store_labels", func=_event_store_labels_txn
+        )
+
+        if not num_rows:
+            yield self.db_pool.updates._end_background_update("event_store_labels")
+
+        return num_rows
diff --git a/synapse/storage/databases/main/events_worker.py b/synapse/storage/databases/main/events_worker.py
new file mode 100644
index 0000000000..a7b7393f6e
--- /dev/null
+++ b/synapse/storage/databases/main/events_worker.py
@@ -0,0 +1,1454 @@
+# -*- coding: utf-8 -*-
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import division
+
+import itertools
+import logging
+import threading
+from collections import namedtuple
+from typing import List, Optional, Tuple
+
+from constantly import NamedConstant, Names
+
+from twisted.internet import defer
+
+from synapse.api.constants import EventTypes
+from synapse.api.errors import NotFoundError, SynapseError
+from synapse.api.room_versions import (
+    KNOWN_ROOM_VERSIONS,
+    EventFormatVersions,
+    RoomVersions,
+)
+from synapse.events import make_event_from_dict
+from synapse.events.utils import prune_event
+from synapse.logging.context import PreserveLoggingContext, current_context
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.replication.slave.storage._slaved_id_tracker import SlavedIdTracker
+from synapse.replication.tcp.streams import BackfillStream
+from synapse.replication.tcp.streams.events import EventsStream
+from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
+from synapse.storage.database import DatabasePool
+from synapse.storage.types import Cursor
+from synapse.storage.util.id_generators import StreamIdGenerator
+from synapse.types import get_domain_from_id
+from synapse.util.caches.descriptors import (
+    Cache,
+    _CacheContext,
+    cached,
+    cachedInlineCallbacks,
+)
+from synapse.util.iterutils import batch_iter
+from synapse.util.metrics import Measure
+
+logger = logging.getLogger(__name__)
+
+
+# These values are used in the `enqueus_event` and `_do_fetch` methods to
+# control how we batch/bulk fetch events from the database.
+# The values are plucked out of thing air to make initial sync run faster
+# on jki.re
+# TODO: Make these configurable.
+EVENT_QUEUE_THREADS = 3  # Max number of threads that will fetch events
+EVENT_QUEUE_ITERATIONS = 3  # No. times we block waiting for requests for events
+EVENT_QUEUE_TIMEOUT_S = 0.1  # Timeout when waiting for requests for events
+
+
+_EventCacheEntry = namedtuple("_EventCacheEntry", ("event", "redacted_event"))
+
+
+class EventRedactBehaviour(Names):
+    """
+    What to do when retrieving a redacted event from the database.
+    """
+
+    AS_IS = NamedConstant()
+    REDACT = NamedConstant()
+    BLOCK = NamedConstant()
+
+
+class EventsWorkerStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(EventsWorkerStore, self).__init__(database, db_conn, hs)
+
+        if hs.config.worker.writers.events == hs.get_instance_name():
+            # We are the process in charge of generating stream ids for events,
+            # so instantiate ID generators based on the database
+            self._stream_id_gen = StreamIdGenerator(
+                db_conn, "events", "stream_ordering",
+            )
+            self._backfill_id_gen = StreamIdGenerator(
+                db_conn,
+                "events",
+                "stream_ordering",
+                step=-1,
+                extra_tables=[("ex_outlier_stream", "event_stream_ordering")],
+            )
+        else:
+            # Another process is in charge of persisting events and generating
+            # stream IDs: rely on the replication streams to let us know which
+            # IDs we can process.
+            self._stream_id_gen = SlavedIdTracker(db_conn, "events", "stream_ordering")
+            self._backfill_id_gen = SlavedIdTracker(
+                db_conn, "events", "stream_ordering", step=-1
+            )
+
+        self._get_event_cache = Cache(
+            "*getEvent*",
+            keylen=3,
+            max_entries=hs.config.caches.event_cache_size,
+            apply_cache_factor_from_config=False,
+        )
+
+        self._event_fetch_lock = threading.Condition()
+        self._event_fetch_list = []
+        self._event_fetch_ongoing = 0
+
+    def process_replication_rows(self, stream_name, instance_name, token, rows):
+        if stream_name == EventsStream.NAME:
+            self._stream_id_gen.advance(token)
+        elif stream_name == BackfillStream.NAME:
+            self._backfill_id_gen.advance(-token)
+
+        super().process_replication_rows(stream_name, instance_name, token, rows)
+
+    def get_received_ts(self, event_id):
+        """Get received_ts (when it was persisted) for the event.
+
+        Raises an exception for unknown events.
+
+        Args:
+            event_id (str)
+
+        Returns:
+            Deferred[int|None]: Timestamp in milliseconds, or None for events
+            that were persisted before received_ts was implemented.
+        """
+        return self.db_pool.simple_select_one_onecol(
+            table="events",
+            keyvalues={"event_id": event_id},
+            retcol="received_ts",
+            desc="get_received_ts",
+        )
+
+    def get_received_ts_by_stream_pos(self, stream_ordering):
+        """Given a stream ordering get an approximate timestamp of when it
+        happened.
+
+        This is done by simply taking the received ts of the first event that
+        has a stream ordering greater than or equal to the given stream pos.
+        If none exists returns the current time, on the assumption that it must
+        have happened recently.
+
+        Args:
+            stream_ordering (int)
+
+        Returns:
+            Deferred[int]
+        """
+
+        def _get_approximate_received_ts_txn(txn):
+            sql = """
+                SELECT received_ts FROM events
+                WHERE stream_ordering >= ?
+                LIMIT 1
+            """
+
+            txn.execute(sql, (stream_ordering,))
+            row = txn.fetchone()
+            if row and row[0]:
+                ts = row[0]
+            else:
+                ts = self.clock.time_msec()
+
+            return ts
+
+        return self.db_pool.runInteraction(
+            "get_approximate_received_ts", _get_approximate_received_ts_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_event(
+        self,
+        event_id: str,
+        redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
+        get_prev_content: bool = False,
+        allow_rejected: bool = False,
+        allow_none: bool = False,
+        check_room_id: Optional[str] = None,
+    ):
+        """Get an event from the database by event_id.
+
+        Args:
+            event_id: The event_id of the event to fetch
+
+            redact_behaviour: Determine what to do with a redacted event. Possible values:
+                * AS_IS - Return the full event body with no redacted content
+                * REDACT - Return the event but with a redacted body
+                * DISALLOW - Do not return redacted events (behave as per allow_none
+                    if the event is redacted)
+
+            get_prev_content: If True and event is a state event,
+                include the previous states content in the unsigned field.
+
+            allow_rejected: If True, return rejected events. Otherwise,
+                behave as per allow_none.
+
+            allow_none: If True, return None if no event found, if
+                False throw a NotFoundError
+
+            check_room_id: if not None, check the room of the found event.
+                If there is a mismatch, behave as per allow_none.
+
+        Returns:
+            Deferred[EventBase|None]
+        """
+        if not isinstance(event_id, str):
+            raise TypeError("Invalid event event_id %r" % (event_id,))
+
+        events = yield self.get_events_as_list(
+            [event_id],
+            redact_behaviour=redact_behaviour,
+            get_prev_content=get_prev_content,
+            allow_rejected=allow_rejected,
+        )
+
+        event = events[0] if events else None
+
+        if event is not None and check_room_id is not None:
+            if event.room_id != check_room_id:
+                event = None
+
+        if event is None and not allow_none:
+            raise NotFoundError("Could not find event %s" % (event_id,))
+
+        return event
+
+    @defer.inlineCallbacks
+    def get_events(
+        self,
+        event_ids: List[str],
+        redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
+        get_prev_content: bool = False,
+        allow_rejected: bool = False,
+    ):
+        """Get events from the database
+
+        Args:
+            event_ids: The event_ids of the events to fetch
+
+            redact_behaviour: Determine what to do with a redacted event. Possible
+                values:
+                * AS_IS - Return the full event body with no redacted content
+                * REDACT - Return the event but with a redacted body
+                * DISALLOW - Do not return redacted events (omit them from the response)
+
+            get_prev_content: If True and event is a state event,
+                include the previous states content in the unsigned field.
+
+            allow_rejected: If True, return rejected events. Otherwise,
+                omits rejeted events from the response.
+
+        Returns:
+            Deferred : Dict from event_id to event.
+        """
+        events = yield self.get_events_as_list(
+            event_ids,
+            redact_behaviour=redact_behaviour,
+            get_prev_content=get_prev_content,
+            allow_rejected=allow_rejected,
+        )
+
+        return {e.event_id: e for e in events}
+
+    @defer.inlineCallbacks
+    def get_events_as_list(
+        self,
+        event_ids: List[str],
+        redact_behaviour: EventRedactBehaviour = EventRedactBehaviour.REDACT,
+        get_prev_content: bool = False,
+        allow_rejected: bool = False,
+    ):
+        """Get events from the database and return in a list in the same order
+        as given by `event_ids` arg.
+
+        Unknown events will be omitted from the response.
+
+        Args:
+            event_ids: The event_ids of the events to fetch
+
+            redact_behaviour: Determine what to do with a redacted event. Possible values:
+                * AS_IS - Return the full event body with no redacted content
+                * REDACT - Return the event but with a redacted body
+                * DISALLOW - Do not return redacted events (omit them from the response)
+
+            get_prev_content: If True and event is a state event,
+                include the previous states content in the unsigned field.
+
+            allow_rejected: If True, return rejected events. Otherwise,
+                omits rejected events from the response.
+
+        Returns:
+            Deferred[list[EventBase]]: List of events fetched from the database. The
+            events are in the same order as `event_ids` arg.
+
+            Note that the returned list may be smaller than the list of event
+            IDs if not all events could be fetched.
+        """
+
+        if not event_ids:
+            return []
+
+        # there may be duplicates so we cast the list to a set
+        event_entry_map = yield self._get_events_from_cache_or_db(
+            set(event_ids), allow_rejected=allow_rejected
+        )
+
+        events = []
+        for event_id in event_ids:
+            entry = event_entry_map.get(event_id, None)
+            if not entry:
+                continue
+
+            if not allow_rejected:
+                assert not entry.event.rejected_reason, (
+                    "rejected event returned from _get_events_from_cache_or_db despite "
+                    "allow_rejected=False"
+                )
+
+            # We may not have had the original event when we received a redaction, so
+            # we have to recheck auth now.
+
+            if not allow_rejected and entry.event.type == EventTypes.Redaction:
+                if entry.event.redacts is None:
+                    # A redacted redaction doesn't have a `redacts` key, in
+                    # which case lets just withhold the event.
+                    #
+                    # Note: Most of the time if the redactions has been
+                    # redacted we still have the un-redacted event in the DB
+                    # and so we'll still see the `redacts` key. However, this
+                    # isn't always true e.g. if we have censored the event.
+                    logger.debug(
+                        "Withholding redaction event %s as we don't have redacts key",
+                        event_id,
+                    )
+                    continue
+
+                redacted_event_id = entry.event.redacts
+                event_map = yield self._get_events_from_cache_or_db([redacted_event_id])
+                original_event_entry = event_map.get(redacted_event_id)
+                if not original_event_entry:
+                    # we don't have the redacted event (or it was rejected).
+                    #
+                    # We assume that the redaction isn't authorized for now; if the
+                    # redacted event later turns up, the redaction will be re-checked,
+                    # and if it is found valid, the original will get redacted before it
+                    # is served to the client.
+                    logger.debug(
+                        "Withholding redaction event %s since we don't (yet) have the "
+                        "original %s",
+                        event_id,
+                        redacted_event_id,
+                    )
+                    continue
+
+                original_event = original_event_entry.event
+                if original_event.type == EventTypes.Create:
+                    # we never serve redactions of Creates to clients.
+                    logger.info(
+                        "Withholding redaction %s of create event %s",
+                        event_id,
+                        redacted_event_id,
+                    )
+                    continue
+
+                if original_event.room_id != entry.event.room_id:
+                    logger.info(
+                        "Withholding redaction %s of event %s from a different room",
+                        event_id,
+                        redacted_event_id,
+                    )
+                    continue
+
+                if entry.event.internal_metadata.need_to_check_redaction():
+                    original_domain = get_domain_from_id(original_event.sender)
+                    redaction_domain = get_domain_from_id(entry.event.sender)
+                    if original_domain != redaction_domain:
+                        # the senders don't match, so this is forbidden
+                        logger.info(
+                            "Withholding redaction %s whose sender domain %s doesn't "
+                            "match that of redacted event %s %s",
+                            event_id,
+                            redaction_domain,
+                            redacted_event_id,
+                            original_domain,
+                        )
+                        continue
+
+                    # Update the cache to save doing the checks again.
+                    entry.event.internal_metadata.recheck_redaction = False
+
+            event = entry.event
+
+            if entry.redacted_event:
+                if redact_behaviour == EventRedactBehaviour.BLOCK:
+                    # Skip this event
+                    continue
+                elif redact_behaviour == EventRedactBehaviour.REDACT:
+                    event = entry.redacted_event
+
+            events.append(event)
+
+            if get_prev_content:
+                if "replaces_state" in event.unsigned:
+                    prev = yield self.get_event(
+                        event.unsigned["replaces_state"],
+                        get_prev_content=False,
+                        allow_none=True,
+                    )
+                    if prev:
+                        event.unsigned = dict(event.unsigned)
+                        event.unsigned["prev_content"] = prev.content
+                        event.unsigned["prev_sender"] = prev.sender
+
+        return events
+
+    @defer.inlineCallbacks
+    def _get_events_from_cache_or_db(self, event_ids, allow_rejected=False):
+        """Fetch a bunch of events from the cache or the database.
+
+        If events are pulled from the database, they will be cached for future lookups.
+
+        Unknown events are omitted from the response.
+
+        Args:
+
+            event_ids (Iterable[str]): The event_ids of the events to fetch
+
+            allow_rejected (bool): Whether to include rejected events. If False,
+                rejected events are omitted from the response.
+
+        Returns:
+            Deferred[Dict[str, _EventCacheEntry]]:
+                map from event id to result
+        """
+        event_entry_map = self._get_events_from_cache(
+            event_ids, allow_rejected=allow_rejected
+        )
+
+        missing_events_ids = [e for e in event_ids if e not in event_entry_map]
+
+        if missing_events_ids:
+            log_ctx = current_context()
+            log_ctx.record_event_fetch(len(missing_events_ids))
+
+            # Note that _get_events_from_db is also responsible for turning db rows
+            # into FrozenEvents (via _get_event_from_row), which involves seeing if
+            # the events have been redacted, and if so pulling the redaction event out
+            # of the database to check it.
+            #
+            missing_events = yield self._get_events_from_db(
+                missing_events_ids, allow_rejected=allow_rejected
+            )
+
+            event_entry_map.update(missing_events)
+
+        return event_entry_map
+
+    def _invalidate_get_event_cache(self, event_id):
+        self._get_event_cache.invalidate((event_id,))
+
+    def _get_events_from_cache(self, events, allow_rejected, update_metrics=True):
+        """Fetch events from the caches
+
+        Args:
+            events (Iterable[str]): list of event_ids to fetch
+            allow_rejected (bool): Whether to return events that were rejected
+            update_metrics (bool): Whether to update the cache hit ratio metrics
+
+        Returns:
+            dict of event_id -> _EventCacheEntry for each event_id in cache. If
+            allow_rejected is `False` then there will still be an entry but it
+            will be `None`
+        """
+        event_map = {}
+
+        for event_id in events:
+            ret = self._get_event_cache.get(
+                (event_id,), None, update_metrics=update_metrics
+            )
+            if not ret:
+                continue
+
+            if allow_rejected or not ret.event.rejected_reason:
+                event_map[event_id] = ret
+            else:
+                event_map[event_id] = None
+
+        return event_map
+
+    def _do_fetch(self, conn):
+        """Takes a database connection and waits for requests for events from
+        the _event_fetch_list queue.
+        """
+        i = 0
+        while True:
+            with self._event_fetch_lock:
+                event_list = self._event_fetch_list
+                self._event_fetch_list = []
+
+                if not event_list:
+                    single_threaded = self.database_engine.single_threaded
+                    if single_threaded or i > EVENT_QUEUE_ITERATIONS:
+                        self._event_fetch_ongoing -= 1
+                        return
+                    else:
+                        self._event_fetch_lock.wait(EVENT_QUEUE_TIMEOUT_S)
+                        i += 1
+                        continue
+                i = 0
+
+            self._fetch_event_list(conn, event_list)
+
+    def _fetch_event_list(self, conn, event_list):
+        """Handle a load of requests from the _event_fetch_list queue
+
+        Args:
+            conn (twisted.enterprise.adbapi.Connection): database connection
+
+            event_list (list[Tuple[list[str], Deferred]]):
+                The fetch requests. Each entry consists of a list of event
+                ids to be fetched, and a deferred to be completed once the
+                events have been fetched.
+
+                The deferreds are callbacked with a dictionary mapping from event id
+                to event row. Note that it may well contain additional events that
+                were not part of this request.
+        """
+        with Measure(self._clock, "_fetch_event_list"):
+            try:
+                events_to_fetch = {
+                    event_id for events, _ in event_list for event_id in events
+                }
+
+                row_dict = self.db_pool.new_transaction(
+                    conn, "do_fetch", [], [], self._fetch_event_rows, events_to_fetch
+                )
+
+                # We only want to resolve deferreds from the main thread
+                def fire():
+                    for _, d in event_list:
+                        d.callback(row_dict)
+
+                with PreserveLoggingContext():
+                    self.hs.get_reactor().callFromThread(fire)
+            except Exception as e:
+                logger.exception("do_fetch")
+
+                # We only want to resolve deferreds from the main thread
+                def fire(evs, exc):
+                    for _, d in evs:
+                        if not d.called:
+                            with PreserveLoggingContext():
+                                d.errback(exc)
+
+                with PreserveLoggingContext():
+                    self.hs.get_reactor().callFromThread(fire, event_list, e)
+
+    @defer.inlineCallbacks
+    def _get_events_from_db(self, event_ids, allow_rejected=False):
+        """Fetch a bunch of events from the database.
+
+        Returned events will be added to the cache for future lookups.
+
+        Unknown events are omitted from the response.
+
+        Args:
+            event_ids (Iterable[str]): The event_ids of the events to fetch
+
+            allow_rejected (bool): Whether to include rejected events. If False,
+                rejected events are omitted from the response.
+
+        Returns:
+            Deferred[Dict[str, _EventCacheEntry]]:
+                map from event id to result. May return extra events which
+                weren't asked for.
+        """
+        fetched_events = {}
+        events_to_fetch = event_ids
+
+        while events_to_fetch:
+            row_map = yield self._enqueue_events(events_to_fetch)
+
+            # we need to recursively fetch any redactions of those events
+            redaction_ids = set()
+            for event_id in events_to_fetch:
+                row = row_map.get(event_id)
+                fetched_events[event_id] = row
+                if row:
+                    redaction_ids.update(row["redactions"])
+
+            events_to_fetch = redaction_ids.difference(fetched_events.keys())
+            if events_to_fetch:
+                logger.debug("Also fetching redaction events %s", events_to_fetch)
+
+        # build a map from event_id to EventBase
+        event_map = {}
+        for event_id, row in fetched_events.items():
+            if not row:
+                continue
+            assert row["event_id"] == event_id
+
+            rejected_reason = row["rejected_reason"]
+
+            if not allow_rejected and rejected_reason:
+                continue
+
+            d = db_to_json(row["json"])
+            internal_metadata = db_to_json(row["internal_metadata"])
+
+            format_version = row["format_version"]
+            if format_version is None:
+                # This means that we stored the event before we had the concept
+                # of a event format version, so it must be a V1 event.
+                format_version = EventFormatVersions.V1
+
+            room_version_id = row["room_version_id"]
+
+            if not room_version_id:
+                # this should only happen for out-of-band membership events
+                if not internal_metadata.get("out_of_band_membership"):
+                    logger.warning(
+                        "Room %s for event %s is unknown", d["room_id"], event_id
+                    )
+                    continue
+
+                # take a wild stab at the room version based on the event format
+                if format_version == EventFormatVersions.V1:
+                    room_version = RoomVersions.V1
+                elif format_version == EventFormatVersions.V2:
+                    room_version = RoomVersions.V3
+                else:
+                    room_version = RoomVersions.V5
+            else:
+                room_version = KNOWN_ROOM_VERSIONS.get(room_version_id)
+                if not room_version:
+                    logger.warning(
+                        "Event %s in room %s has unknown room version %s",
+                        event_id,
+                        d["room_id"],
+                        room_version_id,
+                    )
+                    continue
+
+                if room_version.event_format != format_version:
+                    logger.error(
+                        "Event %s in room %s with version %s has wrong format: "
+                        "expected %s, was %s",
+                        event_id,
+                        d["room_id"],
+                        room_version_id,
+                        room_version.event_format,
+                        format_version,
+                    )
+                    continue
+
+            original_ev = make_event_from_dict(
+                event_dict=d,
+                room_version=room_version,
+                internal_metadata_dict=internal_metadata,
+                rejected_reason=rejected_reason,
+            )
+
+            event_map[event_id] = original_ev
+
+        # finally, we can decide whether each one needs redacting, and build
+        # the cache entries.
+        result_map = {}
+        for event_id, original_ev in event_map.items():
+            redactions = fetched_events[event_id]["redactions"]
+            redacted_event = self._maybe_redact_event_row(
+                original_ev, redactions, event_map
+            )
+
+            cache_entry = _EventCacheEntry(
+                event=original_ev, redacted_event=redacted_event
+            )
+
+            self._get_event_cache.prefill((event_id,), cache_entry)
+            result_map[event_id] = cache_entry
+
+        return result_map
+
+    @defer.inlineCallbacks
+    def _enqueue_events(self, events):
+        """Fetches events from the database using the _event_fetch_list. This
+        allows batch and bulk fetching of events - it allows us to fetch events
+        without having to create a new transaction for each request for events.
+
+        Args:
+            events (Iterable[str]): events to be fetched.
+
+        Returns:
+            Deferred[Dict[str, Dict]]: map from event id to row data from the database.
+                May contain events that weren't requested.
+        """
+
+        events_d = defer.Deferred()
+        with self._event_fetch_lock:
+            self._event_fetch_list.append((events, events_d))
+
+            self._event_fetch_lock.notify()
+
+            if self._event_fetch_ongoing < EVENT_QUEUE_THREADS:
+                self._event_fetch_ongoing += 1
+                should_start = True
+            else:
+                should_start = False
+
+        if should_start:
+            run_as_background_process(
+                "fetch_events", self.db_pool.runWithConnection, self._do_fetch
+            )
+
+        logger.debug("Loading %d events: %s", len(events), events)
+        with PreserveLoggingContext():
+            row_map = yield events_d
+        logger.debug("Loaded %d events (%d rows)", len(events), len(row_map))
+
+        return row_map
+
+    def _fetch_event_rows(self, txn, event_ids):
+        """Fetch event rows from the database
+
+        Events which are not found are omitted from the result.
+
+        The returned per-event dicts contain the following keys:
+
+         * event_id (str)
+
+         * json (str): json-encoded event structure
+
+         * internal_metadata (str): json-encoded internal metadata dict
+
+         * format_version (int|None): The format of the event. Hopefully one
+           of EventFormatVersions. 'None' means the event predates
+           EventFormatVersions (so the event is format V1).
+
+         * room_version_id (str|None): The version of the room which contains the event.
+           Hopefully one of RoomVersions.
+
+           Due to historical reasons, there may be a few events in the database which
+           do not have an associated room; in this case None will be returned here.
+
+         * rejected_reason (str|None): if the event was rejected, the reason
+           why.
+
+         * redactions (List[str]): a list of event-ids which (claim to) redact
+           this event.
+
+        Args:
+            txn (twisted.enterprise.adbapi.Connection):
+            event_ids (Iterable[str]): event IDs to fetch
+
+        Returns:
+            Dict[str, Dict]: a map from event id to event info.
+        """
+        event_dict = {}
+        for evs in batch_iter(event_ids, 200):
+            sql = """\
+                SELECT
+                  e.event_id,
+                  e.internal_metadata,
+                  e.json,
+                  e.format_version,
+                  r.room_version,
+                  rej.reason
+                FROM event_json as e
+                  LEFT JOIN rooms r USING (room_id)
+                  LEFT JOIN rejections as rej USING (event_id)
+                WHERE """
+
+            clause, args = make_in_list_sql_clause(
+                txn.database_engine, "e.event_id", evs
+            )
+
+            txn.execute(sql + clause, args)
+
+            for row in txn:
+                event_id = row[0]
+                event_dict[event_id] = {
+                    "event_id": event_id,
+                    "internal_metadata": row[1],
+                    "json": row[2],
+                    "format_version": row[3],
+                    "room_version_id": row[4],
+                    "rejected_reason": row[5],
+                    "redactions": [],
+                }
+
+            # check for redactions
+            redactions_sql = "SELECT event_id, redacts FROM redactions WHERE "
+
+            clause, args = make_in_list_sql_clause(txn.database_engine, "redacts", evs)
+
+            txn.execute(redactions_sql + clause, args)
+
+            for (redacter, redacted) in txn:
+                d = event_dict.get(redacted)
+                if d:
+                    d["redactions"].append(redacter)
+
+        return event_dict
+
+    def _maybe_redact_event_row(self, original_ev, redactions, event_map):
+        """Given an event object and a list of possible redacting event ids,
+        determine whether to honour any of those redactions and if so return a redacted
+        event.
+
+        Args:
+             original_ev (EventBase):
+             redactions (iterable[str]): list of event ids of potential redaction events
+             event_map (dict[str, EventBase]): other events which have been fetched, in
+                 which we can look up the redaaction events. Map from event id to event.
+
+        Returns:
+            Deferred[EventBase|None]: if the event should be redacted, a pruned
+                event object. Otherwise, None.
+        """
+        if original_ev.type == "m.room.create":
+            # we choose to ignore redactions of m.room.create events.
+            return None
+
+        for redaction_id in redactions:
+            redaction_event = event_map.get(redaction_id)
+            if not redaction_event or redaction_event.rejected_reason:
+                # we don't have the redaction event, or the redaction event was not
+                # authorized.
+                logger.debug(
+                    "%s was redacted by %s but redaction not found/authed",
+                    original_ev.event_id,
+                    redaction_id,
+                )
+                continue
+
+            if redaction_event.room_id != original_ev.room_id:
+                logger.debug(
+                    "%s was redacted by %s but redaction was in a different room!",
+                    original_ev.event_id,
+                    redaction_id,
+                )
+                continue
+
+            # Starting in room version v3, some redactions need to be
+            # rechecked if we didn't have the redacted event at the
+            # time, so we recheck on read instead.
+            if redaction_event.internal_metadata.need_to_check_redaction():
+                expected_domain = get_domain_from_id(original_ev.sender)
+                if get_domain_from_id(redaction_event.sender) == expected_domain:
+                    # This redaction event is allowed. Mark as not needing a recheck.
+                    redaction_event.internal_metadata.recheck_redaction = False
+                else:
+                    # Senders don't match, so the event isn't actually redacted
+                    logger.debug(
+                        "%s was redacted by %s but the senders don't match",
+                        original_ev.event_id,
+                        redaction_id,
+                    )
+                    continue
+
+            logger.debug("Redacting %s due to %s", original_ev.event_id, redaction_id)
+
+            # we found a good redaction event. Redact!
+            redacted_event = prune_event(original_ev)
+            redacted_event.unsigned["redacted_by"] = redaction_id
+
+            # It's fine to add the event directly, since get_pdu_json
+            # will serialise this field correctly
+            redacted_event.unsigned["redacted_because"] = redaction_event
+
+            return redacted_event
+
+        # no valid redaction found for this event
+        return None
+
+    @defer.inlineCallbacks
+    def have_events_in_timeline(self, event_ids):
+        """Given a list of event ids, check if we have already processed and
+        stored them as non outliers.
+        """
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="events",
+            retcols=("event_id",),
+            column="event_id",
+            iterable=list(event_ids),
+            keyvalues={"outlier": False},
+            desc="have_events_in_timeline",
+        )
+
+        return {r["event_id"] for r in rows}
+
+    @defer.inlineCallbacks
+    def have_seen_events(self, event_ids):
+        """Given a list of event ids, check if we have already processed them.
+
+        Args:
+            event_ids (iterable[str]):
+
+        Returns:
+            Deferred[set[str]]: The events we have already seen.
+        """
+        results = set()
+
+        def have_seen_events_txn(txn, chunk):
+            sql = "SELECT event_id FROM events as e WHERE "
+            clause, args = make_in_list_sql_clause(
+                txn.database_engine, "e.event_id", chunk
+            )
+            txn.execute(sql + clause, args)
+            for (event_id,) in txn:
+                results.add(event_id)
+
+        # break the input up into chunks of 100
+        input_iterator = iter(event_ids)
+        for chunk in iter(lambda: list(itertools.islice(input_iterator, 100)), []):
+            yield self.db_pool.runInteraction(
+                "have_seen_events", have_seen_events_txn, chunk
+            )
+        return results
+
+    def _get_total_state_event_counts_txn(self, txn, room_id):
+        """
+        See get_total_state_event_counts.
+        """
+        # We join against the events table as that has an index on room_id
+        sql = """
+            SELECT COUNT(*) FROM state_events
+            INNER JOIN events USING (room_id, event_id)
+            WHERE room_id=?
+        """
+        txn.execute(sql, (room_id,))
+        row = txn.fetchone()
+        return row[0] if row else 0
+
+    def get_total_state_event_counts(self, room_id):
+        """
+        Gets the total number of state events in a room.
+
+        Args:
+            room_id (str)
+
+        Returns:
+            Deferred[int]
+        """
+        return self.db_pool.runInteraction(
+            "get_total_state_event_counts",
+            self._get_total_state_event_counts_txn,
+            room_id,
+        )
+
+    def _get_current_state_event_counts_txn(self, txn, room_id):
+        """
+        See get_current_state_event_counts.
+        """
+        sql = "SELECT COUNT(*) FROM current_state_events WHERE room_id=?"
+        txn.execute(sql, (room_id,))
+        row = txn.fetchone()
+        return row[0] if row else 0
+
+    def get_current_state_event_counts(self, room_id):
+        """
+        Gets the current number of state events in a room.
+
+        Args:
+            room_id (str)
+
+        Returns:
+            Deferred[int]
+        """
+        return self.db_pool.runInteraction(
+            "get_current_state_event_counts",
+            self._get_current_state_event_counts_txn,
+            room_id,
+        )
+
+    @defer.inlineCallbacks
+    def get_room_complexity(self, room_id):
+        """
+        Get a rough approximation of the complexity of the room. This is used by
+        remote servers to decide whether they wish to join the room or not.
+        Higher complexity value indicates that being in the room will consume
+        more resources.
+
+        Args:
+            room_id (str)
+
+        Returns:
+            Deferred[dict[str:int]] of complexity version to complexity.
+        """
+        state_events = yield self.get_current_state_event_counts(room_id)
+
+        # Call this one "v1", so we can introduce new ones as we want to develop
+        # it.
+        complexity_v1 = round(state_events / 500, 2)
+
+        return {"v1": complexity_v1}
+
+    def get_current_backfill_token(self):
+        """The current minimum token that backfilled events have reached"""
+        return -self._backfill_id_gen.get_current_token()
+
+    def get_current_events_token(self):
+        """The current maximum token that events have reached"""
+        return self._stream_id_gen.get_current_token()
+
+    def get_all_new_forward_event_rows(self, last_id, current_id, limit):
+        """Returns new events, for the Events replication stream
+
+        Args:
+            last_id: the last stream_id from the previous batch.
+            current_id: the maximum stream_id to return up to
+            limit: the maximum number of rows to return
+
+        Returns: Deferred[List[Tuple]]
+            a list of events stream rows. Each tuple consists of a stream id as
+            the first element, followed by fields suitable for casting into an
+            EventsStreamRow.
+        """
+
+        def get_all_new_forward_event_rows(txn):
+            sql = (
+                "SELECT e.stream_ordering, e.event_id, e.room_id, e.type,"
+                " state_key, redacts, relates_to_id"
+                " FROM events AS e"
+                " LEFT JOIN redactions USING (event_id)"
+                " LEFT JOIN state_events USING (event_id)"
+                " LEFT JOIN event_relations USING (event_id)"
+                " WHERE ? < stream_ordering AND stream_ordering <= ?"
+                " ORDER BY stream_ordering ASC"
+                " LIMIT ?"
+            )
+            txn.execute(sql, (last_id, current_id, limit))
+            return txn.fetchall()
+
+        return self.db_pool.runInteraction(
+            "get_all_new_forward_event_rows", get_all_new_forward_event_rows
+        )
+
+    def get_ex_outlier_stream_rows(self, last_id, current_id):
+        """Returns de-outliered events, for the Events replication stream
+
+        Args:
+            last_id: the last stream_id from the previous batch.
+            current_id: the maximum stream_id to return up to
+
+        Returns: Deferred[List[Tuple]]
+            a list of events stream rows. Each tuple consists of a stream id as
+            the first element, followed by fields suitable for casting into an
+            EventsStreamRow.
+        """
+
+        def get_ex_outlier_stream_rows_txn(txn):
+            sql = (
+                "SELECT event_stream_ordering, e.event_id, e.room_id, e.type,"
+                " state_key, redacts, relates_to_id"
+                " FROM events AS e"
+                " INNER JOIN ex_outlier_stream USING (event_id)"
+                " LEFT JOIN redactions USING (event_id)"
+                " LEFT JOIN state_events USING (event_id)"
+                " LEFT JOIN event_relations USING (event_id)"
+                " WHERE ? < event_stream_ordering"
+                " AND event_stream_ordering <= ?"
+                " ORDER BY event_stream_ordering ASC"
+            )
+
+            txn.execute(sql, (last_id, current_id))
+            return txn.fetchall()
+
+        return self.db_pool.runInteraction(
+            "get_ex_outlier_stream_rows", get_ex_outlier_stream_rows_txn
+        )
+
+    async def get_all_new_backfill_event_rows(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, list]], int, bool]:
+        """Get updates for backfill replication stream, including all new
+        backfilled events and events that have gone from being outliers to not.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_new_backfill_event_rows(txn):
+            sql = (
+                "SELECT -e.stream_ordering, e.event_id, e.room_id, e.type,"
+                " state_key, redacts, relates_to_id"
+                " FROM events AS e"
+                " LEFT JOIN redactions USING (event_id)"
+                " LEFT JOIN state_events USING (event_id)"
+                " LEFT JOIN event_relations USING (event_id)"
+                " WHERE ? > stream_ordering AND stream_ordering >= ?"
+                " ORDER BY stream_ordering ASC"
+                " LIMIT ?"
+            )
+            txn.execute(sql, (-last_id, -current_id, limit))
+            new_event_updates = [(row[0], row[1:]) for row in txn]
+
+            limited = False
+            if len(new_event_updates) == limit:
+                upper_bound = new_event_updates[-1][0]
+                limited = True
+            else:
+                upper_bound = current_id
+
+            sql = (
+                "SELECT -event_stream_ordering, e.event_id, e.room_id, e.type,"
+                " state_key, redacts, relates_to_id"
+                " FROM events AS e"
+                " INNER JOIN ex_outlier_stream USING (event_id)"
+                " LEFT JOIN redactions USING (event_id)"
+                " LEFT JOIN state_events USING (event_id)"
+                " LEFT JOIN event_relations USING (event_id)"
+                " WHERE ? > event_stream_ordering"
+                " AND event_stream_ordering >= ?"
+                " ORDER BY event_stream_ordering DESC"
+            )
+            txn.execute(sql, (-last_id, -upper_bound))
+            new_event_updates.extend((row[0], row[1:]) for row in txn)
+
+            if len(new_event_updates) >= limit:
+                upper_bound = new_event_updates[-1][0]
+                limited = True
+
+            return new_event_updates, upper_bound, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_new_backfill_event_rows", get_all_new_backfill_event_rows
+        )
+
+    async def get_all_updated_current_state_deltas(
+        self, from_token: int, to_token: int, target_row_count: int
+    ) -> Tuple[List[Tuple], int, bool]:
+        """Fetch updates from current_state_delta_stream
+
+        Args:
+            from_token: The previous stream token. Updates from this stream id will
+                be excluded.
+
+            to_token: The current stream token (ie the upper limit). Updates up to this
+                stream id will be included (modulo the 'limit' param)
+
+            target_row_count: The number of rows to try to return. If more rows are
+                available, we will set 'limited' in the result. In the event of a large
+                batch, we may return more rows than this.
+        Returns:
+            A triplet `(updates, new_last_token, limited)`, where:
+               * `updates` is a list of database tuples.
+               * `new_last_token` is the new position in stream.
+               * `limited` is whether there are more updates to fetch.
+        """
+
+        def get_all_updated_current_state_deltas_txn(txn):
+            sql = """
+                SELECT stream_id, room_id, type, state_key, event_id
+                FROM current_state_delta_stream
+                WHERE ? < stream_id AND stream_id <= ?
+                ORDER BY stream_id ASC LIMIT ?
+            """
+            txn.execute(sql, (from_token, to_token, target_row_count))
+            return txn.fetchall()
+
+        def get_deltas_for_stream_id_txn(txn, stream_id):
+            sql = """
+                SELECT stream_id, room_id, type, state_key, event_id
+                FROM current_state_delta_stream
+                WHERE stream_id = ?
+            """
+            txn.execute(sql, [stream_id])
+            return txn.fetchall()
+
+        # we need to make sure that, for every stream id in the results, we get *all*
+        # the rows with that stream id.
+
+        rows = await self.db_pool.runInteraction(
+            "get_all_updated_current_state_deltas",
+            get_all_updated_current_state_deltas_txn,
+        )  # type: List[Tuple]
+
+        # if we've got fewer rows than the limit, we're good
+        if len(rows) < target_row_count:
+            return rows, to_token, False
+
+        # we hit the limit, so reduce the upper limit so that we exclude the stream id
+        # of the last row in the result.
+        assert rows[-1][0] <= to_token
+        to_token = rows[-1][0] - 1
+
+        # search backwards through the list for the point to truncate
+        for idx in range(len(rows) - 1, 0, -1):
+            if rows[idx - 1][0] <= to_token:
+                return rows[:idx], to_token, True
+
+        # bother. We didn't get a full set of changes for even a single
+        # stream id. let's run the query again, without a row limit, but for
+        # just one stream id.
+        to_token += 1
+        rows = await self.db_pool.runInteraction(
+            "get_deltas_for_stream_id", get_deltas_for_stream_id_txn, to_token
+        )
+
+        return rows, to_token, True
+
+    @cached(num_args=5, max_entries=10)
+    def get_all_new_events(
+        self,
+        last_backfill_id,
+        last_forward_id,
+        current_backfill_id,
+        current_forward_id,
+        limit,
+    ):
+        """Get all the new events that have arrived at the server either as
+        new events or as backfilled events"""
+        have_backfill_events = last_backfill_id != current_backfill_id
+        have_forward_events = last_forward_id != current_forward_id
+
+        if not have_backfill_events and not have_forward_events:
+            return defer.succeed(AllNewEventsResult([], [], [], [], []))
+
+        def get_all_new_events_txn(txn):
+            sql = (
+                "SELECT e.stream_ordering, e.event_id, e.room_id, e.type,"
+                " state_key, redacts"
+                " FROM events AS e"
+                " LEFT JOIN redactions USING (event_id)"
+                " LEFT JOIN state_events USING (event_id)"
+                " WHERE ? < stream_ordering AND stream_ordering <= ?"
+                " ORDER BY stream_ordering ASC"
+                " LIMIT ?"
+            )
+            if have_forward_events:
+                txn.execute(sql, (last_forward_id, current_forward_id, limit))
+                new_forward_events = txn.fetchall()
+
+                if len(new_forward_events) == limit:
+                    upper_bound = new_forward_events[-1][0]
+                else:
+                    upper_bound = current_forward_id
+
+                sql = (
+                    "SELECT event_stream_ordering, event_id, state_group"
+                    " FROM ex_outlier_stream"
+                    " WHERE ? > event_stream_ordering"
+                    " AND event_stream_ordering >= ?"
+                    " ORDER BY event_stream_ordering DESC"
+                )
+                txn.execute(sql, (last_forward_id, upper_bound))
+                forward_ex_outliers = txn.fetchall()
+            else:
+                new_forward_events = []
+                forward_ex_outliers = []
+
+            sql = (
+                "SELECT -e.stream_ordering, e.event_id, e.room_id, e.type,"
+                " state_key, redacts"
+                " FROM events AS e"
+                " LEFT JOIN redactions USING (event_id)"
+                " LEFT JOIN state_events USING (event_id)"
+                " WHERE ? > stream_ordering AND stream_ordering >= ?"
+                " ORDER BY stream_ordering DESC"
+                " LIMIT ?"
+            )
+            if have_backfill_events:
+                txn.execute(sql, (-last_backfill_id, -current_backfill_id, limit))
+                new_backfill_events = txn.fetchall()
+
+                if len(new_backfill_events) == limit:
+                    upper_bound = new_backfill_events[-1][0]
+                else:
+                    upper_bound = current_backfill_id
+
+                sql = (
+                    "SELECT -event_stream_ordering, event_id, state_group"
+                    " FROM ex_outlier_stream"
+                    " WHERE ? > event_stream_ordering"
+                    " AND event_stream_ordering >= ?"
+                    " ORDER BY event_stream_ordering DESC"
+                )
+                txn.execute(sql, (-last_backfill_id, -upper_bound))
+                backward_ex_outliers = txn.fetchall()
+            else:
+                new_backfill_events = []
+                backward_ex_outliers = []
+
+            return AllNewEventsResult(
+                new_forward_events,
+                new_backfill_events,
+                forward_ex_outliers,
+                backward_ex_outliers,
+            )
+
+        return self.db_pool.runInteraction("get_all_new_events", get_all_new_events_txn)
+
+    async def is_event_after(self, event_id1, event_id2):
+        """Returns True if event_id1 is after event_id2 in the stream
+        """
+        to_1, so_1 = await self.get_event_ordering(event_id1)
+        to_2, so_2 = await self.get_event_ordering(event_id2)
+        return (to_1, so_1) > (to_2, so_2)
+
+    @cachedInlineCallbacks(max_entries=5000)
+    def get_event_ordering(self, event_id):
+        res = yield self.db_pool.simple_select_one(
+            table="events",
+            retcols=["topological_ordering", "stream_ordering"],
+            keyvalues={"event_id": event_id},
+            allow_none=True,
+        )
+
+        if not res:
+            raise SynapseError(404, "Could not find event %s" % (event_id,))
+
+        return (int(res["topological_ordering"]), int(res["stream_ordering"]))
+
+    def get_next_event_to_expire(self):
+        """Retrieve the entry with the lowest expiry timestamp in the event_expiry
+        table, or None if there's no more event to expire.
+
+        Returns: Deferred[Optional[Tuple[str, int]]]
+            A tuple containing the event ID as its first element and an expiry timestamp
+            as its second one, if there's at least one row in the event_expiry table.
+            None otherwise.
+        """
+
+        def get_next_event_to_expire_txn(txn):
+            txn.execute(
+                """
+                SELECT event_id, expiry_ts FROM event_expiry
+                ORDER BY expiry_ts ASC LIMIT 1
+                """
+            )
+
+            return txn.fetchone()
+
+        return self.db_pool.runInteraction(
+            desc="get_next_event_to_expire", func=get_next_event_to_expire_txn
+        )
+
+    @cached(tree=True, cache_context=True)
+    async def get_unread_message_count_for_user(
+        self, room_id: str, user_id: str, cache_context: _CacheContext,
+    ) -> int:
+        """Retrieve the count of unread messages for the given room and user.
+
+        Args:
+            room_id: The ID of the room to count unread messages in.
+            user_id: The ID of the user to count unread messages for.
+
+        Returns:
+            The number of unread messages for the given user in the given room.
+        """
+        with Measure(self._clock, "get_unread_message_count_for_user"):
+            last_read_event_id = await self.get_last_receipt_event_id_for_user(
+                user_id=user_id,
+                room_id=room_id,
+                receipt_type="m.read",
+                on_invalidate=cache_context.invalidate,
+            )
+
+            return await self.db_pool.runInteraction(
+                "get_unread_message_count_for_user",
+                self._get_unread_message_count_for_user_txn,
+                user_id,
+                room_id,
+                last_read_event_id,
+            )
+
+    def _get_unread_message_count_for_user_txn(
+        self,
+        txn: Cursor,
+        user_id: str,
+        room_id: str,
+        last_read_event_id: Optional[str],
+    ) -> int:
+        if last_read_event_id:
+            # Get the stream ordering for the last read event.
+            stream_ordering = self.db_pool.simple_select_one_onecol_txn(
+                txn=txn,
+                table="events",
+                keyvalues={"room_id": room_id, "event_id": last_read_event_id},
+                retcol="stream_ordering",
+            )
+        else:
+            # If there's no read receipt for that room, it probably means the user hasn't
+            # opened it yet, in which case use the stream ID of their join event.
+            # We can't just set it to 0 otherwise messages from other local users from
+            # before this user joined will be counted as well.
+            txn.execute(
+                """
+                SELECT stream_ordering FROM local_current_membership
+                LEFT JOIN events USING (event_id, room_id)
+                WHERE membership = 'join'
+                    AND user_id = ?
+                    AND room_id = ?
+                """,
+                (user_id, room_id),
+            )
+            row = txn.fetchone()
+
+            if row is None:
+                return 0
+
+            stream_ordering = row[0]
+
+        # Count the messages that qualify as unread after the stream ordering we've just
+        # retrieved.
+        sql = """
+            SELECT COUNT(*) FROM events
+            WHERE sender != ? AND room_id = ? AND stream_ordering > ? AND count_as_unread
+        """
+
+        txn.execute(sql, (user_id, room_id, stream_ordering))
+        row = txn.fetchone()
+
+        return row[0] if row else 0
+
+
+AllNewEventsResult = namedtuple(
+    "AllNewEventsResult",
+    [
+        "new_forward_events",
+        "new_backfill_events",
+        "forward_ex_outliers",
+        "backward_ex_outliers",
+    ],
+)
diff --git a/synapse/storage/databases/main/filtering.py b/synapse/storage/databases/main/filtering.py
new file mode 100644
index 0000000000..cae6bda80e
--- /dev/null
+++ b/synapse/storage/databases/main/filtering.py
@@ -0,0 +1,74 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015, 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from canonicaljson import encode_canonical_json
+
+from synapse.api.errors import Codes, SynapseError
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.util.caches.descriptors import cachedInlineCallbacks
+
+
+class FilteringStore(SQLBaseStore):
+    @cachedInlineCallbacks(num_args=2)
+    def get_user_filter(self, user_localpart, filter_id):
+        # filter_id is BIGINT UNSIGNED, so if it isn't a number, fail
+        # with a coherent error message rather than 500 M_UNKNOWN.
+        try:
+            int(filter_id)
+        except ValueError:
+            raise SynapseError(400, "Invalid filter ID", Codes.INVALID_PARAM)
+
+        def_json = yield self.db_pool.simple_select_one_onecol(
+            table="user_filters",
+            keyvalues={"user_id": user_localpart, "filter_id": filter_id},
+            retcol="filter_json",
+            allow_none=False,
+            desc="get_user_filter",
+        )
+
+        return db_to_json(def_json)
+
+    def add_user_filter(self, user_localpart, user_filter):
+        def_json = encode_canonical_json(user_filter)
+
+        # Need an atomic transaction to SELECT the maximal ID so far then
+        # INSERT a new one
+        def _do_txn(txn):
+            sql = (
+                "SELECT filter_id FROM user_filters "
+                "WHERE user_id = ? AND filter_json = ?"
+            )
+            txn.execute(sql, (user_localpart, bytearray(def_json)))
+            filter_id_response = txn.fetchone()
+            if filter_id_response is not None:
+                return filter_id_response[0]
+
+            sql = "SELECT MAX(filter_id) FROM user_filters WHERE user_id = ?"
+            txn.execute(sql, (user_localpart,))
+            max_id = txn.fetchone()[0]
+            if max_id is None:
+                filter_id = 0
+            else:
+                filter_id = max_id + 1
+
+            sql = (
+                "INSERT INTO user_filters (user_id, filter_id, filter_json)"
+                "VALUES(?, ?, ?)"
+            )
+            txn.execute(sql, (user_localpart, filter_id, bytearray(def_json)))
+
+            return filter_id
+
+        return self.db_pool.runInteraction("add_user_filter", _do_txn)
diff --git a/synapse/storage/databases/main/group_server.py b/synapse/storage/databases/main/group_server.py
new file mode 100644
index 0000000000..a98181f445
--- /dev/null
+++ b/synapse/storage/databases/main/group_server.py
@@ -0,0 +1,1297 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from typing import List, Tuple
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.api.errors import SynapseError
+from synapse.storage._base import SQLBaseStore, db_to_json
+
+# The category ID for the "default" category. We don't store as null in the
+# database to avoid the fun of null != null
+_DEFAULT_CATEGORY_ID = ""
+_DEFAULT_ROLE_ID = ""
+
+
+class GroupServerWorkerStore(SQLBaseStore):
+    def get_group(self, group_id):
+        return self.db_pool.simple_select_one(
+            table="groups",
+            keyvalues={"group_id": group_id},
+            retcols=(
+                "name",
+                "short_description",
+                "long_description",
+                "avatar_url",
+                "is_public",
+                "join_policy",
+            ),
+            allow_none=True,
+            desc="get_group",
+        )
+
+    def get_users_in_group(self, group_id, include_private=False):
+        # TODO: Pagination
+
+        keyvalues = {"group_id": group_id}
+        if not include_private:
+            keyvalues["is_public"] = True
+
+        return self.db_pool.simple_select_list(
+            table="group_users",
+            keyvalues=keyvalues,
+            retcols=("user_id", "is_public", "is_admin"),
+            desc="get_users_in_group",
+        )
+
+    def get_invited_users_in_group(self, group_id):
+        # TODO: Pagination
+
+        return self.db_pool.simple_select_onecol(
+            table="group_invites",
+            keyvalues={"group_id": group_id},
+            retcol="user_id",
+            desc="get_invited_users_in_group",
+        )
+
+    def get_rooms_in_group(self, group_id: str, include_private: bool = False):
+        """Retrieve the rooms that belong to a given group. Does not return rooms that
+        lack members.
+
+        Args:
+            group_id: The ID of the group to query for rooms
+            include_private: Whether to return private rooms in results
+
+        Returns:
+            Deferred[List[Dict[str, str|bool]]]: A list of dictionaries, each in the
+            form of:
+
+            {
+              "room_id": "!a_room_id:example.com",  # The ID of the room
+              "is_public": False                    # Whether this is a public room or not
+            }
+        """
+        # TODO: Pagination
+
+        def _get_rooms_in_group_txn(txn):
+            sql = """
+            SELECT room_id, is_public FROM group_rooms
+                WHERE group_id = ?
+                AND room_id IN (
+                    SELECT group_rooms.room_id FROM group_rooms
+                    LEFT JOIN room_stats_current ON
+                        group_rooms.room_id = room_stats_current.room_id
+                        AND joined_members > 0
+                        AND local_users_in_room > 0
+                    LEFT JOIN rooms ON
+                        group_rooms.room_id = rooms.room_id
+                        AND (room_version <> '') = ?
+                )
+            """
+            args = [group_id, False]
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                args += [True]
+
+            txn.execute(sql, args)
+
+            return [
+                {"room_id": room_id, "is_public": is_public}
+                for room_id, is_public in txn
+            ]
+
+        return self.db_pool.runInteraction(
+            "get_rooms_in_group", _get_rooms_in_group_txn
+        )
+
+    def get_rooms_for_summary_by_category(
+        self, group_id: str, include_private: bool = False,
+    ):
+        """Get the rooms and categories that should be included in a summary request
+
+        Args:
+            group_id: The ID of the group to query the summary for
+            include_private: Whether to return private rooms in results
+
+        Returns:
+            Deferred[Tuple[List, Dict]]: A tuple containing:
+
+                * A list of dictionaries with the keys:
+                    * "room_id": str, the room ID
+                    * "is_public": bool, whether the room is public
+                    * "category_id": str|None, the category ID if set, else None
+                    * "order": int, the sort order of rooms
+
+                * A dictionary with the key:
+                    * category_id (str): a dictionary with the keys:
+                        * "is_public": bool, whether the category is public
+                        * "profile": str, the category profile
+                        * "order": int, the sort order of rooms in this category
+        """
+
+        def _get_rooms_for_summary_txn(txn):
+            keyvalues = {"group_id": group_id}
+            if not include_private:
+                keyvalues["is_public"] = True
+
+            sql = """
+                SELECT room_id, is_public, category_id, room_order
+                FROM group_summary_rooms
+                WHERE group_id = ?
+                AND room_id IN (
+                    SELECT group_rooms.room_id FROM group_rooms
+                    LEFT JOIN room_stats_current ON
+                        group_rooms.room_id = room_stats_current.room_id
+                        AND joined_members > 0
+                        AND local_users_in_room > 0
+                    LEFT JOIN rooms ON
+                        group_rooms.room_id = rooms.room_id
+                        AND (room_version <> '') = ?
+                )
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, False, True))
+            else:
+                txn.execute(sql, (group_id, False))
+
+            rooms = [
+                {
+                    "room_id": row[0],
+                    "is_public": row[1],
+                    "category_id": row[2] if row[2] != _DEFAULT_CATEGORY_ID else None,
+                    "order": row[3],
+                }
+                for row in txn
+            ]
+
+            sql = """
+                SELECT category_id, is_public, profile, cat_order
+                FROM group_summary_room_categories
+                INNER JOIN group_room_categories USING (group_id, category_id)
+                WHERE group_id = ?
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, True))
+            else:
+                txn.execute(sql, (group_id,))
+
+            categories = {
+                row[0]: {
+                    "is_public": row[1],
+                    "profile": db_to_json(row[2]),
+                    "order": row[3],
+                }
+                for row in txn
+            }
+
+            return rooms, categories
+
+        return self.db_pool.runInteraction(
+            "get_rooms_for_summary", _get_rooms_for_summary_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_group_categories(self, group_id):
+        rows = yield self.db_pool.simple_select_list(
+            table="group_room_categories",
+            keyvalues={"group_id": group_id},
+            retcols=("category_id", "is_public", "profile"),
+            desc="get_group_categories",
+        )
+
+        return {
+            row["category_id"]: {
+                "is_public": row["is_public"],
+                "profile": db_to_json(row["profile"]),
+            }
+            for row in rows
+        }
+
+    @defer.inlineCallbacks
+    def get_group_category(self, group_id, category_id):
+        category = yield self.db_pool.simple_select_one(
+            table="group_room_categories",
+            keyvalues={"group_id": group_id, "category_id": category_id},
+            retcols=("is_public", "profile"),
+            desc="get_group_category",
+        )
+
+        category["profile"] = db_to_json(category["profile"])
+
+        return category
+
+    @defer.inlineCallbacks
+    def get_group_roles(self, group_id):
+        rows = yield self.db_pool.simple_select_list(
+            table="group_roles",
+            keyvalues={"group_id": group_id},
+            retcols=("role_id", "is_public", "profile"),
+            desc="get_group_roles",
+        )
+
+        return {
+            row["role_id"]: {
+                "is_public": row["is_public"],
+                "profile": db_to_json(row["profile"]),
+            }
+            for row in rows
+        }
+
+    @defer.inlineCallbacks
+    def get_group_role(self, group_id, role_id):
+        role = yield self.db_pool.simple_select_one(
+            table="group_roles",
+            keyvalues={"group_id": group_id, "role_id": role_id},
+            retcols=("is_public", "profile"),
+            desc="get_group_role",
+        )
+
+        role["profile"] = db_to_json(role["profile"])
+
+        return role
+
+    def get_local_groups_for_room(self, room_id):
+        """Get all of the local group that contain a given room
+        Args:
+            room_id (str): The ID of a room
+        Returns:
+            Deferred[list[str]]: A twisted.Deferred containing a list of group ids
+                containing this room
+        """
+        return self.db_pool.simple_select_onecol(
+            table="group_rooms",
+            keyvalues={"room_id": room_id},
+            retcol="group_id",
+            desc="get_local_groups_for_room",
+        )
+
+    def get_users_for_summary_by_role(self, group_id, include_private=False):
+        """Get the users and roles that should be included in a summary request
+
+        Returns ([users], [roles])
+        """
+
+        def _get_users_for_summary_txn(txn):
+            keyvalues = {"group_id": group_id}
+            if not include_private:
+                keyvalues["is_public"] = True
+
+            sql = """
+                SELECT user_id, is_public, role_id, user_order
+                FROM group_summary_users
+                WHERE group_id = ?
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, True))
+            else:
+                txn.execute(sql, (group_id,))
+
+            users = [
+                {
+                    "user_id": row[0],
+                    "is_public": row[1],
+                    "role_id": row[2] if row[2] != _DEFAULT_ROLE_ID else None,
+                    "order": row[3],
+                }
+                for row in txn
+            ]
+
+            sql = """
+                SELECT role_id, is_public, profile, role_order
+                FROM group_summary_roles
+                INNER JOIN group_roles USING (group_id, role_id)
+                WHERE group_id = ?
+            """
+
+            if not include_private:
+                sql += " AND is_public = ?"
+                txn.execute(sql, (group_id, True))
+            else:
+                txn.execute(sql, (group_id,))
+
+            roles = {
+                row[0]: {
+                    "is_public": row[1],
+                    "profile": db_to_json(row[2]),
+                    "order": row[3],
+                }
+                for row in txn
+            }
+
+            return users, roles
+
+        return self.db_pool.runInteraction(
+            "get_users_for_summary_by_role", _get_users_for_summary_txn
+        )
+
+    def is_user_in_group(self, user_id, group_id):
+        return self.db_pool.simple_select_one_onecol(
+            table="group_users",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            retcol="user_id",
+            allow_none=True,
+            desc="is_user_in_group",
+        ).addCallback(lambda r: bool(r))
+
+    def is_user_admin_in_group(self, group_id, user_id):
+        return self.db_pool.simple_select_one_onecol(
+            table="group_users",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            retcol="is_admin",
+            allow_none=True,
+            desc="is_user_admin_in_group",
+        )
+
+    def is_user_invited_to_local_group(self, group_id, user_id):
+        """Has the group server invited a user?
+        """
+        return self.db_pool.simple_select_one_onecol(
+            table="group_invites",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            retcol="user_id",
+            desc="is_user_invited_to_local_group",
+            allow_none=True,
+        )
+
+    def get_users_membership_info_in_group(self, group_id, user_id):
+        """Get a dict describing the membership of a user in a group.
+
+        Example if joined:
+
+            {
+                "membership": "join",
+                "is_public": True,
+                "is_privileged": False,
+            }
+
+        Returns an empty dict if the user is not join/invite/etc
+        """
+
+        def _get_users_membership_in_group_txn(txn):
+            row = self.db_pool.simple_select_one_txn(
+                txn,
+                table="group_users",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+                retcols=("is_admin", "is_public"),
+                allow_none=True,
+            )
+
+            if row:
+                return {
+                    "membership": "join",
+                    "is_public": row["is_public"],
+                    "is_privileged": row["is_admin"],
+                }
+
+            row = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="group_invites",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+                retcol="user_id",
+                allow_none=True,
+            )
+
+            if row:
+                return {"membership": "invite"}
+
+            return {}
+
+        return self.db_pool.runInteraction(
+            "get_users_membership_info_in_group", _get_users_membership_in_group_txn
+        )
+
+    def get_publicised_groups_for_user(self, user_id):
+        """Get all groups a user is publicising
+        """
+        return self.db_pool.simple_select_onecol(
+            table="local_group_membership",
+            keyvalues={"user_id": user_id, "membership": "join", "is_publicised": True},
+            retcol="group_id",
+            desc="get_publicised_groups_for_user",
+        )
+
+    def get_attestations_need_renewals(self, valid_until_ms):
+        """Get all attestations that need to be renewed until givent time
+        """
+
+        def _get_attestations_need_renewals_txn(txn):
+            sql = """
+                SELECT group_id, user_id FROM group_attestations_renewals
+                WHERE valid_until_ms <= ?
+            """
+            txn.execute(sql, (valid_until_ms,))
+            return self.db_pool.cursor_to_dict(txn)
+
+        return self.db_pool.runInteraction(
+            "get_attestations_need_renewals", _get_attestations_need_renewals_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_remote_attestation(self, group_id, user_id):
+        """Get the attestation that proves the remote agrees that the user is
+        in the group.
+        """
+        row = yield self.db_pool.simple_select_one(
+            table="group_attestations_remote",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            retcols=("valid_until_ms", "attestation_json"),
+            desc="get_remote_attestation",
+            allow_none=True,
+        )
+
+        now = int(self._clock.time_msec())
+        if row and now < row["valid_until_ms"]:
+            return db_to_json(row["attestation_json"])
+
+        return None
+
+    def get_joined_groups(self, user_id):
+        return self.db_pool.simple_select_onecol(
+            table="local_group_membership",
+            keyvalues={"user_id": user_id, "membership": "join"},
+            retcol="group_id",
+            desc="get_joined_groups",
+        )
+
+    def get_all_groups_for_user(self, user_id, now_token):
+        def _get_all_groups_for_user_txn(txn):
+            sql = """
+                SELECT group_id, type, membership, u.content
+                FROM local_group_updates AS u
+                INNER JOIN local_group_membership USING (group_id, user_id)
+                WHERE user_id = ? AND membership != 'leave'
+                    AND stream_id <= ?
+            """
+            txn.execute(sql, (user_id, now_token))
+            return [
+                {
+                    "group_id": row[0],
+                    "type": row[1],
+                    "membership": row[2],
+                    "content": db_to_json(row[3]),
+                }
+                for row in txn
+            ]
+
+        return self.db_pool.runInteraction(
+            "get_all_groups_for_user", _get_all_groups_for_user_txn
+        )
+
+    def get_groups_changes_for_user(self, user_id, from_token, to_token):
+        from_token = int(from_token)
+        has_changed = self._group_updates_stream_cache.has_entity_changed(
+            user_id, from_token
+        )
+        if not has_changed:
+            return defer.succeed([])
+
+        def _get_groups_changes_for_user_txn(txn):
+            sql = """
+                SELECT group_id, membership, type, u.content
+                FROM local_group_updates AS u
+                INNER JOIN local_group_membership USING (group_id, user_id)
+                WHERE user_id = ? AND ? < stream_id AND stream_id <= ?
+            """
+            txn.execute(sql, (user_id, from_token, to_token))
+            return [
+                {
+                    "group_id": group_id,
+                    "membership": membership,
+                    "type": gtype,
+                    "content": db_to_json(content_json),
+                }
+                for group_id, membership, gtype, content_json in txn
+            ]
+
+        return self.db_pool.runInteraction(
+            "get_groups_changes_for_user", _get_groups_changes_for_user_txn
+        )
+
+    async def get_all_groups_changes(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for groups replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        last_id = int(last_id)
+        has_changed = self._group_updates_stream_cache.has_any_entity_changed(last_id)
+
+        if not has_changed:
+            return [], current_id, False
+
+        def _get_all_groups_changes_txn(txn):
+            sql = """
+                SELECT stream_id, group_id, user_id, type, content
+                FROM local_group_updates
+                WHERE ? < stream_id AND stream_id <= ?
+                LIMIT ?
+            """
+            txn.execute(sql, (last_id, current_id, limit))
+            updates = [
+                (stream_id, (group_id, user_id, gtype, db_to_json(content_json)))
+                for stream_id, group_id, user_id, gtype, content_json in txn
+            ]
+
+            limited = False
+            upto_token = current_id
+            if len(updates) >= limit:
+                upto_token = updates[-1][0]
+                limited = True
+
+            return updates, upto_token, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_groups_changes", _get_all_groups_changes_txn
+        )
+
+
+class GroupServerStore(GroupServerWorkerStore):
+    def set_group_join_policy(self, group_id, join_policy):
+        """Set the join policy of a group.
+
+        join_policy can be one of:
+         * "invite"
+         * "open"
+        """
+        return self.db_pool.simple_update_one(
+            table="groups",
+            keyvalues={"group_id": group_id},
+            updatevalues={"join_policy": join_policy},
+            desc="set_group_join_policy",
+        )
+
+    def add_room_to_summary(self, group_id, room_id, category_id, order, is_public):
+        return self.db_pool.runInteraction(
+            "add_room_to_summary",
+            self._add_room_to_summary_txn,
+            group_id,
+            room_id,
+            category_id,
+            order,
+            is_public,
+        )
+
+    def _add_room_to_summary_txn(
+        self, txn, group_id, room_id, category_id, order, is_public
+    ):
+        """Add (or update) room's entry in summary.
+
+        Args:
+            group_id (str)
+            room_id (str)
+            category_id (str): If not None then adds the category to the end of
+                the summary if its not already there. [Optional]
+            order (int): If not None inserts the room at that position, e.g.
+                an order of 1 will put the room first. Otherwise, the room gets
+                added to the end.
+        """
+        room_in_group = self.db_pool.simple_select_one_onecol_txn(
+            txn,
+            table="group_rooms",
+            keyvalues={"group_id": group_id, "room_id": room_id},
+            retcol="room_id",
+            allow_none=True,
+        )
+        if not room_in_group:
+            raise SynapseError(400, "room not in group")
+
+        if category_id is None:
+            category_id = _DEFAULT_CATEGORY_ID
+        else:
+            cat_exists = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="group_room_categories",
+                keyvalues={"group_id": group_id, "category_id": category_id},
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not cat_exists:
+                raise SynapseError(400, "Category doesn't exist")
+
+            # TODO: Check category is part of summary already
+            cat_exists = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="group_summary_room_categories",
+                keyvalues={"group_id": group_id, "category_id": category_id},
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not cat_exists:
+                # If not, add it with an order larger than all others
+                txn.execute(
+                    """
+                    INSERT INTO group_summary_room_categories
+                    (group_id, category_id, cat_order)
+                    SELECT ?, ?, COALESCE(MAX(cat_order), 0) + 1
+                    FROM group_summary_room_categories
+                    WHERE group_id = ? AND category_id = ?
+                """,
+                    (group_id, category_id, group_id, category_id),
+                )
+
+        existing = self.db_pool.simple_select_one_txn(
+            txn,
+            table="group_summary_rooms",
+            keyvalues={
+                "group_id": group_id,
+                "room_id": room_id,
+                "category_id": category_id,
+            },
+            retcols=("room_order", "is_public"),
+            allow_none=True,
+        )
+
+        if order is not None:
+            # Shuffle other room orders that come after the given order
+            sql = """
+                UPDATE group_summary_rooms SET room_order = room_order + 1
+                WHERE group_id = ? AND category_id = ? AND room_order >= ?
+            """
+            txn.execute(sql, (group_id, category_id, order))
+        elif not existing:
+            sql = """
+                SELECT COALESCE(MAX(room_order), 0) + 1 FROM group_summary_rooms
+                WHERE group_id = ? AND category_id = ?
+            """
+            txn.execute(sql, (group_id, category_id))
+            (order,) = txn.fetchone()
+
+        if existing:
+            to_update = {}
+            if order is not None:
+                to_update["room_order"] = order
+            if is_public is not None:
+                to_update["is_public"] = is_public
+            self.db_pool.simple_update_txn(
+                txn,
+                table="group_summary_rooms",
+                keyvalues={
+                    "group_id": group_id,
+                    "category_id": category_id,
+                    "room_id": room_id,
+                },
+                values=to_update,
+            )
+        else:
+            if is_public is None:
+                is_public = True
+
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="group_summary_rooms",
+                values={
+                    "group_id": group_id,
+                    "category_id": category_id,
+                    "room_id": room_id,
+                    "room_order": order,
+                    "is_public": is_public,
+                },
+            )
+
+    def remove_room_from_summary(self, group_id, room_id, category_id):
+        if category_id is None:
+            category_id = _DEFAULT_CATEGORY_ID
+
+        return self.db_pool.simple_delete(
+            table="group_summary_rooms",
+            keyvalues={
+                "group_id": group_id,
+                "category_id": category_id,
+                "room_id": room_id,
+            },
+            desc="remove_room_from_summary",
+        )
+
+    def upsert_group_category(self, group_id, category_id, profile, is_public):
+        """Add/update room category for group
+        """
+        insertion_values = {}
+        update_values = {"category_id": category_id}  # This cannot be empty
+
+        if profile is None:
+            insertion_values["profile"] = "{}"
+        else:
+            update_values["profile"] = json.dumps(profile)
+
+        if is_public is None:
+            insertion_values["is_public"] = True
+        else:
+            update_values["is_public"] = is_public
+
+        return self.db_pool.simple_upsert(
+            table="group_room_categories",
+            keyvalues={"group_id": group_id, "category_id": category_id},
+            values=update_values,
+            insertion_values=insertion_values,
+            desc="upsert_group_category",
+        )
+
+    def remove_group_category(self, group_id, category_id):
+        return self.db_pool.simple_delete(
+            table="group_room_categories",
+            keyvalues={"group_id": group_id, "category_id": category_id},
+            desc="remove_group_category",
+        )
+
+    def upsert_group_role(self, group_id, role_id, profile, is_public):
+        """Add/remove user role
+        """
+        insertion_values = {}
+        update_values = {"role_id": role_id}  # This cannot be empty
+
+        if profile is None:
+            insertion_values["profile"] = "{}"
+        else:
+            update_values["profile"] = json.dumps(profile)
+
+        if is_public is None:
+            insertion_values["is_public"] = True
+        else:
+            update_values["is_public"] = is_public
+
+        return self.db_pool.simple_upsert(
+            table="group_roles",
+            keyvalues={"group_id": group_id, "role_id": role_id},
+            values=update_values,
+            insertion_values=insertion_values,
+            desc="upsert_group_role",
+        )
+
+    def remove_group_role(self, group_id, role_id):
+        return self.db_pool.simple_delete(
+            table="group_roles",
+            keyvalues={"group_id": group_id, "role_id": role_id},
+            desc="remove_group_role",
+        )
+
+    def add_user_to_summary(self, group_id, user_id, role_id, order, is_public):
+        return self.db_pool.runInteraction(
+            "add_user_to_summary",
+            self._add_user_to_summary_txn,
+            group_id,
+            user_id,
+            role_id,
+            order,
+            is_public,
+        )
+
+    def _add_user_to_summary_txn(
+        self, txn, group_id, user_id, role_id, order, is_public
+    ):
+        """Add (or update) user's entry in summary.
+
+        Args:
+            group_id (str)
+            user_id (str)
+            role_id (str): If not None then adds the role to the end of
+                the summary if its not already there. [Optional]
+            order (int): If not None inserts the user at that position, e.g.
+                an order of 1 will put the user first. Otherwise, the user gets
+                added to the end.
+        """
+        user_in_group = self.db_pool.simple_select_one_onecol_txn(
+            txn,
+            table="group_users",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            retcol="user_id",
+            allow_none=True,
+        )
+        if not user_in_group:
+            raise SynapseError(400, "user not in group")
+
+        if role_id is None:
+            role_id = _DEFAULT_ROLE_ID
+        else:
+            role_exists = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="group_roles",
+                keyvalues={"group_id": group_id, "role_id": role_id},
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not role_exists:
+                raise SynapseError(400, "Role doesn't exist")
+
+            # TODO: Check role is part of the summary already
+            role_exists = self.db_pool.simple_select_one_onecol_txn(
+                txn,
+                table="group_summary_roles",
+                keyvalues={"group_id": group_id, "role_id": role_id},
+                retcol="group_id",
+                allow_none=True,
+            )
+            if not role_exists:
+                # If not, add it with an order larger than all others
+                txn.execute(
+                    """
+                    INSERT INTO group_summary_roles
+                    (group_id, role_id, role_order)
+                    SELECT ?, ?, COALESCE(MAX(role_order), 0) + 1
+                    FROM group_summary_roles
+                    WHERE group_id = ? AND role_id = ?
+                """,
+                    (group_id, role_id, group_id, role_id),
+                )
+
+        existing = self.db_pool.simple_select_one_txn(
+            txn,
+            table="group_summary_users",
+            keyvalues={"group_id": group_id, "user_id": user_id, "role_id": role_id},
+            retcols=("user_order", "is_public"),
+            allow_none=True,
+        )
+
+        if order is not None:
+            # Shuffle other users orders that come after the given order
+            sql = """
+                UPDATE group_summary_users SET user_order = user_order + 1
+                WHERE group_id = ? AND role_id = ? AND user_order >= ?
+            """
+            txn.execute(sql, (group_id, role_id, order))
+        elif not existing:
+            sql = """
+                SELECT COALESCE(MAX(user_order), 0) + 1 FROM group_summary_users
+                WHERE group_id = ? AND role_id = ?
+            """
+            txn.execute(sql, (group_id, role_id))
+            (order,) = txn.fetchone()
+
+        if existing:
+            to_update = {}
+            if order is not None:
+                to_update["user_order"] = order
+            if is_public is not None:
+                to_update["is_public"] = is_public
+            self.db_pool.simple_update_txn(
+                txn,
+                table="group_summary_users",
+                keyvalues={
+                    "group_id": group_id,
+                    "role_id": role_id,
+                    "user_id": user_id,
+                },
+                values=to_update,
+            )
+        else:
+            if is_public is None:
+                is_public = True
+
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="group_summary_users",
+                values={
+                    "group_id": group_id,
+                    "role_id": role_id,
+                    "user_id": user_id,
+                    "user_order": order,
+                    "is_public": is_public,
+                },
+            )
+
+    def remove_user_from_summary(self, group_id, user_id, role_id):
+        if role_id is None:
+            role_id = _DEFAULT_ROLE_ID
+
+        return self.db_pool.simple_delete(
+            table="group_summary_users",
+            keyvalues={"group_id": group_id, "role_id": role_id, "user_id": user_id},
+            desc="remove_user_from_summary",
+        )
+
+    def add_group_invite(self, group_id, user_id):
+        """Record that the group server has invited a user
+        """
+        return self.db_pool.simple_insert(
+            table="group_invites",
+            values={"group_id": group_id, "user_id": user_id},
+            desc="add_group_invite",
+        )
+
+    def add_user_to_group(
+        self,
+        group_id,
+        user_id,
+        is_admin=False,
+        is_public=True,
+        local_attestation=None,
+        remote_attestation=None,
+    ):
+        """Add a user to the group server.
+
+        Args:
+            group_id (str)
+            user_id (str)
+            is_admin (bool)
+            is_public (bool)
+            local_attestation (dict): The attestation the GS created to give
+                to the remote server. Optional if the user and group are on the
+                same server
+            remote_attestation (dict): The attestation given to GS by remote
+                server. Optional if the user and group are on the same server
+        """
+
+        def _add_user_to_group_txn(txn):
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="group_users",
+                values={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                    "is_admin": is_admin,
+                    "is_public": is_public,
+                },
+            )
+
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_invites",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+            )
+
+            if local_attestation:
+                self.db_pool.simple_insert_txn(
+                    txn,
+                    table="group_attestations_renewals",
+                    values={
+                        "group_id": group_id,
+                        "user_id": user_id,
+                        "valid_until_ms": local_attestation["valid_until_ms"],
+                    },
+                )
+            if remote_attestation:
+                self.db_pool.simple_insert_txn(
+                    txn,
+                    table="group_attestations_remote",
+                    values={
+                        "group_id": group_id,
+                        "user_id": user_id,
+                        "valid_until_ms": remote_attestation["valid_until_ms"],
+                        "attestation_json": json.dumps(remote_attestation),
+                    },
+                )
+
+        return self.db_pool.runInteraction("add_user_to_group", _add_user_to_group_txn)
+
+    def remove_user_from_group(self, group_id, user_id):
+        def _remove_user_from_group_txn(txn):
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_users",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_invites",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_attestations_renewals",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_attestations_remote",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_summary_users",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+            )
+
+        return self.db_pool.runInteraction(
+            "remove_user_from_group", _remove_user_from_group_txn
+        )
+
+    def add_room_to_group(self, group_id, room_id, is_public):
+        return self.db_pool.simple_insert(
+            table="group_rooms",
+            values={"group_id": group_id, "room_id": room_id, "is_public": is_public},
+            desc="add_room_to_group",
+        )
+
+    def update_room_in_group_visibility(self, group_id, room_id, is_public):
+        return self.db_pool.simple_update(
+            table="group_rooms",
+            keyvalues={"group_id": group_id, "room_id": room_id},
+            updatevalues={"is_public": is_public},
+            desc="update_room_in_group_visibility",
+        )
+
+    def remove_room_from_group(self, group_id, room_id):
+        def _remove_room_from_group_txn(txn):
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_rooms",
+                keyvalues={"group_id": group_id, "room_id": room_id},
+            )
+
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="group_summary_rooms",
+                keyvalues={"group_id": group_id, "room_id": room_id},
+            )
+
+        return self.db_pool.runInteraction(
+            "remove_room_from_group", _remove_room_from_group_txn
+        )
+
+    def update_group_publicity(self, group_id, user_id, publicise):
+        """Update whether the user is publicising their membership of the group
+        """
+        return self.db_pool.simple_update_one(
+            table="local_group_membership",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            updatevalues={"is_publicised": publicise},
+            desc="update_group_publicity",
+        )
+
+    @defer.inlineCallbacks
+    def register_user_group_membership(
+        self,
+        group_id,
+        user_id,
+        membership,
+        is_admin=False,
+        content={},
+        local_attestation=None,
+        remote_attestation=None,
+        is_publicised=False,
+    ):
+        """Registers that a local user is a member of a (local or remote) group.
+
+        Args:
+            group_id (str)
+            user_id (str)
+            membership (str)
+            is_admin (bool)
+            content (dict): Content of the membership, e.g. includes the inviter
+                if the user has been invited.
+            local_attestation (dict): If remote group then store the fact that we
+                have given out an attestation, else None.
+            remote_attestation (dict): If remote group then store the remote
+                attestation from the group, else None.
+        """
+
+        def _register_user_group_membership_txn(txn, next_id):
+            # TODO: Upsert?
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="local_group_membership",
+                keyvalues={"group_id": group_id, "user_id": user_id},
+            )
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="local_group_membership",
+                values={
+                    "group_id": group_id,
+                    "user_id": user_id,
+                    "is_admin": is_admin,
+                    "membership": membership,
+                    "is_publicised": is_publicised,
+                    "content": json.dumps(content),
+                },
+            )
+
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="local_group_updates",
+                values={
+                    "stream_id": next_id,
+                    "group_id": group_id,
+                    "user_id": user_id,
+                    "type": "membership",
+                    "content": json.dumps(
+                        {"membership": membership, "content": content}
+                    ),
+                },
+            )
+            self._group_updates_stream_cache.entity_has_changed(user_id, next_id)
+
+            # TODO: Insert profile to ensure it comes down stream if its a join.
+
+            if membership == "join":
+                if local_attestation:
+                    self.db_pool.simple_insert_txn(
+                        txn,
+                        table="group_attestations_renewals",
+                        values={
+                            "group_id": group_id,
+                            "user_id": user_id,
+                            "valid_until_ms": local_attestation["valid_until_ms"],
+                        },
+                    )
+                if remote_attestation:
+                    self.db_pool.simple_insert_txn(
+                        txn,
+                        table="group_attestations_remote",
+                        values={
+                            "group_id": group_id,
+                            "user_id": user_id,
+                            "valid_until_ms": remote_attestation["valid_until_ms"],
+                            "attestation_json": json.dumps(remote_attestation),
+                        },
+                    )
+            else:
+                self.db_pool.simple_delete_txn(
+                    txn,
+                    table="group_attestations_renewals",
+                    keyvalues={"group_id": group_id, "user_id": user_id},
+                )
+                self.db_pool.simple_delete_txn(
+                    txn,
+                    table="group_attestations_remote",
+                    keyvalues={"group_id": group_id, "user_id": user_id},
+                )
+
+            return next_id
+
+        with self._group_updates_id_gen.get_next() as next_id:
+            res = yield self.db_pool.runInteraction(
+                "register_user_group_membership",
+                _register_user_group_membership_txn,
+                next_id,
+            )
+        return res
+
+    @defer.inlineCallbacks
+    def create_group(
+        self, group_id, user_id, name, avatar_url, short_description, long_description
+    ):
+        yield self.db_pool.simple_insert(
+            table="groups",
+            values={
+                "group_id": group_id,
+                "name": name,
+                "avatar_url": avatar_url,
+                "short_description": short_description,
+                "long_description": long_description,
+                "is_public": True,
+            },
+            desc="create_group",
+        )
+
+    @defer.inlineCallbacks
+    def update_group_profile(self, group_id, profile):
+        yield self.db_pool.simple_update_one(
+            table="groups",
+            keyvalues={"group_id": group_id},
+            updatevalues=profile,
+            desc="update_group_profile",
+        )
+
+    def update_attestation_renewal(self, group_id, user_id, attestation):
+        """Update an attestation that we have renewed
+        """
+        return self.db_pool.simple_update_one(
+            table="group_attestations_renewals",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            updatevalues={"valid_until_ms": attestation["valid_until_ms"]},
+            desc="update_attestation_renewal",
+        )
+
+    def update_remote_attestion(self, group_id, user_id, attestation):
+        """Update an attestation that a remote has renewed
+        """
+        return self.db_pool.simple_update_one(
+            table="group_attestations_remote",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            updatevalues={
+                "valid_until_ms": attestation["valid_until_ms"],
+                "attestation_json": json.dumps(attestation),
+            },
+            desc="update_remote_attestion",
+        )
+
+    def remove_attestation_renewal(self, group_id, user_id):
+        """Remove an attestation that we thought we should renew, but actually
+        shouldn't. Ideally this would never get called as we would never
+        incorrectly try and do attestations for local users on local groups.
+
+        Args:
+            group_id (str)
+            user_id (str)
+        """
+        return self.db_pool.simple_delete(
+            table="group_attestations_renewals",
+            keyvalues={"group_id": group_id, "user_id": user_id},
+            desc="remove_attestation_renewal",
+        )
+
+    def get_group_stream_token(self):
+        return self._group_updates_id_gen.get_current_token()
+
+    def delete_group(self, group_id):
+        """Deletes a group fully from the database.
+
+        Args:
+            group_id (str)
+
+        Returns:
+            Deferred
+        """
+
+        def _delete_group_txn(txn):
+            tables = [
+                "groups",
+                "group_users",
+                "group_invites",
+                "group_rooms",
+                "group_summary_rooms",
+                "group_summary_room_categories",
+                "group_room_categories",
+                "group_summary_users",
+                "group_summary_roles",
+                "group_roles",
+                "group_attestations_renewals",
+                "group_attestations_remote",
+            ]
+
+            for table in tables:
+                self.db_pool.simple_delete_txn(
+                    txn, table=table, keyvalues={"group_id": group_id}
+                )
+
+        return self.db_pool.runInteraction("delete_group", _delete_group_txn)
diff --git a/synapse/storage/databases/main/keys.py b/synapse/storage/databases/main/keys.py
new file mode 100644
index 0000000000..384e9c5eb0
--- /dev/null
+++ b/synapse/storage/databases/main/keys.py
@@ -0,0 +1,210 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2019 New Vector Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import itertools
+import logging
+
+from signedjson.key import decode_verify_key_bytes
+
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.keys import FetchKeyResult
+from synapse.util.caches.descriptors import cached, cachedList
+from synapse.util.iterutils import batch_iter
+
+logger = logging.getLogger(__name__)
+
+
+db_binary_type = memoryview
+
+
+class KeyStore(SQLBaseStore):
+    """Persistence for signature verification keys
+    """
+
+    @cached()
+    def _get_server_verify_key(self, server_name_and_key_id):
+        raise NotImplementedError()
+
+    @cachedList(
+        cached_method_name="_get_server_verify_key", list_name="server_name_and_key_ids"
+    )
+    def get_server_verify_keys(self, server_name_and_key_ids):
+        """
+        Args:
+            server_name_and_key_ids (iterable[Tuple[str, str]]):
+                iterable of (server_name, key-id) tuples to fetch keys for
+
+        Returns:
+            Deferred: resolves to dict[Tuple[str, str], FetchKeyResult|None]:
+                map from (server_name, key_id) -> FetchKeyResult, or None if the key is
+                unknown
+        """
+        keys = {}
+
+        def _get_keys(txn, batch):
+            """Processes a batch of keys to fetch, and adds the result to `keys`."""
+
+            # batch_iter always returns tuples so it's safe to do len(batch)
+            sql = (
+                "SELECT server_name, key_id, verify_key, ts_valid_until_ms "
+                "FROM server_signature_keys WHERE 1=0"
+            ) + " OR (server_name=? AND key_id=?)" * len(batch)
+
+            txn.execute(sql, tuple(itertools.chain.from_iterable(batch)))
+
+            for row in txn:
+                server_name, key_id, key_bytes, ts_valid_until_ms = row
+
+                if ts_valid_until_ms is None:
+                    # Old keys may be stored with a ts_valid_until_ms of null,
+                    # in which case we treat this as if it was set to `0`, i.e.
+                    # it won't match key requests that define a minimum
+                    # `ts_valid_until_ms`.
+                    ts_valid_until_ms = 0
+
+                res = FetchKeyResult(
+                    verify_key=decode_verify_key_bytes(key_id, bytes(key_bytes)),
+                    valid_until_ts=ts_valid_until_ms,
+                )
+                keys[(server_name, key_id)] = res
+
+        def _txn(txn):
+            for batch in batch_iter(server_name_and_key_ids, 50):
+                _get_keys(txn, batch)
+            return keys
+
+        return self.db_pool.runInteraction("get_server_verify_keys", _txn)
+
+    def store_server_verify_keys(self, from_server, ts_added_ms, verify_keys):
+        """Stores NACL verification keys for remote servers.
+        Args:
+            from_server (str): Where the verification keys were looked up
+            ts_added_ms (int): The time to record that the key was added
+            verify_keys (iterable[tuple[str, str, FetchKeyResult]]):
+                keys to be stored. Each entry is a triplet of
+                (server_name, key_id, key).
+        """
+        key_values = []
+        value_values = []
+        invalidations = []
+        for server_name, key_id, fetch_result in verify_keys:
+            key_values.append((server_name, key_id))
+            value_values.append(
+                (
+                    from_server,
+                    ts_added_ms,
+                    fetch_result.valid_until_ts,
+                    db_binary_type(fetch_result.verify_key.encode()),
+                )
+            )
+            # invalidate takes a tuple corresponding to the params of
+            # _get_server_verify_key. _get_server_verify_key only takes one
+            # param, which is itself the 2-tuple (server_name, key_id).
+            invalidations.append((server_name, key_id))
+
+        def _invalidate(res):
+            f = self._get_server_verify_key.invalidate
+            for i in invalidations:
+                f((i,))
+            return res
+
+        return self.db_pool.runInteraction(
+            "store_server_verify_keys",
+            self.db_pool.simple_upsert_many_txn,
+            table="server_signature_keys",
+            key_names=("server_name", "key_id"),
+            key_values=key_values,
+            value_names=(
+                "from_server",
+                "ts_added_ms",
+                "ts_valid_until_ms",
+                "verify_key",
+            ),
+            value_values=value_values,
+        ).addCallback(_invalidate)
+
+    def store_server_keys_json(
+        self, server_name, key_id, from_server, ts_now_ms, ts_expires_ms, key_json_bytes
+    ):
+        """Stores the JSON bytes for a set of keys from a server
+        The JSON should be signed by the originating server, the intermediate
+        server, and by this server. Updates the value for the
+        (server_name, key_id, from_server) triplet if one already existed.
+        Args:
+            server_name (str): The name of the server.
+            key_id (str): The identifer of the key this JSON is for.
+            from_server (str): The server this JSON was fetched from.
+            ts_now_ms (int): The time now in milliseconds.
+            ts_valid_until_ms (int): The time when this json stops being valid.
+            key_json (bytes): The encoded JSON.
+        """
+        return self.db_pool.simple_upsert(
+            table="server_keys_json",
+            keyvalues={
+                "server_name": server_name,
+                "key_id": key_id,
+                "from_server": from_server,
+            },
+            values={
+                "server_name": server_name,
+                "key_id": key_id,
+                "from_server": from_server,
+                "ts_added_ms": ts_now_ms,
+                "ts_valid_until_ms": ts_expires_ms,
+                "key_json": db_binary_type(key_json_bytes),
+            },
+            desc="store_server_keys_json",
+        )
+
+    def get_server_keys_json(self, server_keys):
+        """Retrive the key json for a list of server_keys and key ids.
+        If no keys are found for a given server, key_id and source then
+        that server, key_id, and source triplet entry will be an empty list.
+        The JSON is returned as a byte array so that it can be efficiently
+        used in an HTTP response.
+        Args:
+            server_keys (list): List of (server_name, key_id, source) triplets.
+        Returns:
+            Deferred[dict[Tuple[str, str, str|None], list[dict]]]:
+                Dict mapping (server_name, key_id, source) triplets to lists of dicts
+        """
+
+        def _get_server_keys_json_txn(txn):
+            results = {}
+            for server_name, key_id, from_server in server_keys:
+                keyvalues = {"server_name": server_name}
+                if key_id is not None:
+                    keyvalues["key_id"] = key_id
+                if from_server is not None:
+                    keyvalues["from_server"] = from_server
+                rows = self.db_pool.simple_select_list_txn(
+                    txn,
+                    "server_keys_json",
+                    keyvalues=keyvalues,
+                    retcols=(
+                        "key_id",
+                        "from_server",
+                        "ts_added_ms",
+                        "ts_valid_until_ms",
+                        "key_json",
+                    ),
+                )
+                results[(server_name, key_id, from_server)] = rows
+            return results
+
+        return self.db_pool.runInteraction(
+            "get_server_keys_json", _get_server_keys_json_txn
+        )
diff --git a/synapse/storage/databases/main/media_repository.py b/synapse/storage/databases/main/media_repository.py
new file mode 100644
index 0000000000..80fc1cd009
--- /dev/null
+++ b/synapse/storage/databases/main/media_repository.py
@@ -0,0 +1,398 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool
+
+
+class MediaRepositoryBackgroundUpdateStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(MediaRepositoryBackgroundUpdateStore, self).__init__(
+            database, db_conn, hs
+        )
+
+        self.db_pool.updates.register_background_index_update(
+            update_name="local_media_repository_url_idx",
+            index_name="local_media_repository_url_idx",
+            table="local_media_repository",
+            columns=["created_ts"],
+            where_clause="url_cache IS NOT NULL",
+        )
+
+
+class MediaRepositoryStore(MediaRepositoryBackgroundUpdateStore):
+    """Persistence for attachments and avatars"""
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(MediaRepositoryStore, self).__init__(database, db_conn, hs)
+
+    def get_local_media(self, media_id):
+        """Get the metadata for a local piece of media
+        Returns:
+            None if the media_id doesn't exist.
+        """
+        return self.db_pool.simple_select_one(
+            "local_media_repository",
+            {"media_id": media_id},
+            (
+                "media_type",
+                "media_length",
+                "upload_name",
+                "created_ts",
+                "quarantined_by",
+                "url_cache",
+            ),
+            allow_none=True,
+            desc="get_local_media",
+        )
+
+    def store_local_media(
+        self,
+        media_id,
+        media_type,
+        time_now_ms,
+        upload_name,
+        media_length,
+        user_id,
+        url_cache=None,
+    ):
+        return self.db_pool.simple_insert(
+            "local_media_repository",
+            {
+                "media_id": media_id,
+                "media_type": media_type,
+                "created_ts": time_now_ms,
+                "upload_name": upload_name,
+                "media_length": media_length,
+                "user_id": user_id.to_string(),
+                "url_cache": url_cache,
+            },
+            desc="store_local_media",
+        )
+
+    def mark_local_media_as_safe(self, media_id: str):
+        """Mark a local media as safe from quarantining."""
+        return self.db_pool.simple_update_one(
+            table="local_media_repository",
+            keyvalues={"media_id": media_id},
+            updatevalues={"safe_from_quarantine": True},
+            desc="mark_local_media_as_safe",
+        )
+
+    def get_url_cache(self, url, ts):
+        """Get the media_id and ts for a cached URL as of the given timestamp
+        Returns:
+            None if the URL isn't cached.
+        """
+
+        def get_url_cache_txn(txn):
+            # get the most recently cached result (relative to the given ts)
+            sql = (
+                "SELECT response_code, etag, expires_ts, og, media_id, download_ts"
+                " FROM local_media_repository_url_cache"
+                " WHERE url = ? AND download_ts <= ?"
+                " ORDER BY download_ts DESC LIMIT 1"
+            )
+            txn.execute(sql, (url, ts))
+            row = txn.fetchone()
+
+            if not row:
+                # ...or if we've requested a timestamp older than the oldest
+                # copy in the cache, return the oldest copy (if any)
+                sql = (
+                    "SELECT response_code, etag, expires_ts, og, media_id, download_ts"
+                    " FROM local_media_repository_url_cache"
+                    " WHERE url = ? AND download_ts > ?"
+                    " ORDER BY download_ts ASC LIMIT 1"
+                )
+                txn.execute(sql, (url, ts))
+                row = txn.fetchone()
+
+            if not row:
+                return None
+
+            return dict(
+                zip(
+                    (
+                        "response_code",
+                        "etag",
+                        "expires_ts",
+                        "og",
+                        "media_id",
+                        "download_ts",
+                    ),
+                    row,
+                )
+            )
+
+        return self.db_pool.runInteraction("get_url_cache", get_url_cache_txn)
+
+    def store_url_cache(
+        self, url, response_code, etag, expires_ts, og, media_id, download_ts
+    ):
+        return self.db_pool.simple_insert(
+            "local_media_repository_url_cache",
+            {
+                "url": url,
+                "response_code": response_code,
+                "etag": etag,
+                "expires_ts": expires_ts,
+                "og": og,
+                "media_id": media_id,
+                "download_ts": download_ts,
+            },
+            desc="store_url_cache",
+        )
+
+    def get_local_media_thumbnails(self, media_id):
+        return self.db_pool.simple_select_list(
+            "local_media_repository_thumbnails",
+            {"media_id": media_id},
+            (
+                "thumbnail_width",
+                "thumbnail_height",
+                "thumbnail_method",
+                "thumbnail_type",
+                "thumbnail_length",
+            ),
+            desc="get_local_media_thumbnails",
+        )
+
+    def store_local_thumbnail(
+        self,
+        media_id,
+        thumbnail_width,
+        thumbnail_height,
+        thumbnail_type,
+        thumbnail_method,
+        thumbnail_length,
+    ):
+        return self.db_pool.simple_insert(
+            "local_media_repository_thumbnails",
+            {
+                "media_id": media_id,
+                "thumbnail_width": thumbnail_width,
+                "thumbnail_height": thumbnail_height,
+                "thumbnail_method": thumbnail_method,
+                "thumbnail_type": thumbnail_type,
+                "thumbnail_length": thumbnail_length,
+            },
+            desc="store_local_thumbnail",
+        )
+
+    def get_cached_remote_media(self, origin, media_id):
+        return self.db_pool.simple_select_one(
+            "remote_media_cache",
+            {"media_origin": origin, "media_id": media_id},
+            (
+                "media_type",
+                "media_length",
+                "upload_name",
+                "created_ts",
+                "filesystem_id",
+                "quarantined_by",
+            ),
+            allow_none=True,
+            desc="get_cached_remote_media",
+        )
+
+    def store_cached_remote_media(
+        self,
+        origin,
+        media_id,
+        media_type,
+        media_length,
+        time_now_ms,
+        upload_name,
+        filesystem_id,
+    ):
+        return self.db_pool.simple_insert(
+            "remote_media_cache",
+            {
+                "media_origin": origin,
+                "media_id": media_id,
+                "media_type": media_type,
+                "media_length": media_length,
+                "created_ts": time_now_ms,
+                "upload_name": upload_name,
+                "filesystem_id": filesystem_id,
+                "last_access_ts": time_now_ms,
+            },
+            desc="store_cached_remote_media",
+        )
+
+    def update_cached_last_access_time(self, local_media, remote_media, time_ms):
+        """Updates the last access time of the given media
+
+        Args:
+            local_media (iterable[str]): Set of media_ids
+            remote_media (iterable[(str, str)]): Set of (server_name, media_id)
+            time_ms: Current time in milliseconds
+        """
+
+        def update_cache_txn(txn):
+            sql = (
+                "UPDATE remote_media_cache SET last_access_ts = ?"
+                " WHERE media_origin = ? AND media_id = ?"
+            )
+
+            txn.executemany(
+                sql,
+                (
+                    (time_ms, media_origin, media_id)
+                    for media_origin, media_id in remote_media
+                ),
+            )
+
+            sql = (
+                "UPDATE local_media_repository SET last_access_ts = ?"
+                " WHERE media_id = ?"
+            )
+
+            txn.executemany(sql, ((time_ms, media_id) for media_id in local_media))
+
+        return self.db_pool.runInteraction(
+            "update_cached_last_access_time", update_cache_txn
+        )
+
+    def get_remote_media_thumbnails(self, origin, media_id):
+        return self.db_pool.simple_select_list(
+            "remote_media_cache_thumbnails",
+            {"media_origin": origin, "media_id": media_id},
+            (
+                "thumbnail_width",
+                "thumbnail_height",
+                "thumbnail_method",
+                "thumbnail_type",
+                "thumbnail_length",
+                "filesystem_id",
+            ),
+            desc="get_remote_media_thumbnails",
+        )
+
+    def store_remote_media_thumbnail(
+        self,
+        origin,
+        media_id,
+        filesystem_id,
+        thumbnail_width,
+        thumbnail_height,
+        thumbnail_type,
+        thumbnail_method,
+        thumbnail_length,
+    ):
+        return self.db_pool.simple_insert(
+            "remote_media_cache_thumbnails",
+            {
+                "media_origin": origin,
+                "media_id": media_id,
+                "thumbnail_width": thumbnail_width,
+                "thumbnail_height": thumbnail_height,
+                "thumbnail_method": thumbnail_method,
+                "thumbnail_type": thumbnail_type,
+                "thumbnail_length": thumbnail_length,
+                "filesystem_id": filesystem_id,
+            },
+            desc="store_remote_media_thumbnail",
+        )
+
+    def get_remote_media_before(self, before_ts):
+        sql = (
+            "SELECT media_origin, media_id, filesystem_id"
+            " FROM remote_media_cache"
+            " WHERE last_access_ts < ?"
+        )
+
+        return self.db_pool.execute(
+            "get_remote_media_before", self.db_pool.cursor_to_dict, sql, before_ts
+        )
+
+    def delete_remote_media(self, media_origin, media_id):
+        def delete_remote_media_txn(txn):
+            self.db_pool.simple_delete_txn(
+                txn,
+                "remote_media_cache",
+                keyvalues={"media_origin": media_origin, "media_id": media_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                "remote_media_cache_thumbnails",
+                keyvalues={"media_origin": media_origin, "media_id": media_id},
+            )
+
+        return self.db_pool.runInteraction(
+            "delete_remote_media", delete_remote_media_txn
+        )
+
+    def get_expired_url_cache(self, now_ts):
+        sql = (
+            "SELECT media_id FROM local_media_repository_url_cache"
+            " WHERE expires_ts < ?"
+            " ORDER BY expires_ts ASC"
+            " LIMIT 500"
+        )
+
+        def _get_expired_url_cache_txn(txn):
+            txn.execute(sql, (now_ts,))
+            return [row[0] for row in txn]
+
+        return self.db_pool.runInteraction(
+            "get_expired_url_cache", _get_expired_url_cache_txn
+        )
+
+    async def delete_url_cache(self, media_ids):
+        if len(media_ids) == 0:
+            return
+
+        sql = "DELETE FROM local_media_repository_url_cache WHERE media_id = ?"
+
+        def _delete_url_cache_txn(txn):
+            txn.executemany(sql, [(media_id,) for media_id in media_ids])
+
+        return await self.db_pool.runInteraction(
+            "delete_url_cache", _delete_url_cache_txn
+        )
+
+    def get_url_cache_media_before(self, before_ts):
+        sql = (
+            "SELECT media_id FROM local_media_repository"
+            " WHERE created_ts < ? AND url_cache IS NOT NULL"
+            " ORDER BY created_ts ASC"
+            " LIMIT 500"
+        )
+
+        def _get_url_cache_media_before_txn(txn):
+            txn.execute(sql, (before_ts,))
+            return [row[0] for row in txn]
+
+        return self.db_pool.runInteraction(
+            "get_url_cache_media_before", _get_url_cache_media_before_txn
+        )
+
+    async def delete_url_cache_media(self, media_ids):
+        if len(media_ids) == 0:
+            return
+
+        def _delete_url_cache_media_txn(txn):
+            sql = "DELETE FROM local_media_repository WHERE media_id = ?"
+
+            txn.executemany(sql, [(media_id,) for media_id in media_ids])
+
+            sql = "DELETE FROM local_media_repository_thumbnails WHERE media_id = ?"
+
+            txn.executemany(sql, [(media_id,) for media_id in media_ids])
+
+        return await self.db_pool.runInteraction(
+            "delete_url_cache_media", _delete_url_cache_media_txn
+        )
diff --git a/synapse/storage/databases/main/metrics.py b/synapse/storage/databases/main/metrics.py
new file mode 100644
index 0000000000..baa7a5092a
--- /dev/null
+++ b/synapse/storage/databases/main/metrics.py
@@ -0,0 +1,130 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import typing
+from collections import Counter
+
+from twisted.internet import defer
+
+from synapse.metrics import BucketCollector
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.event_push_actions import (
+    EventPushActionsWorkerStore,
+)
+
+
+class ServerMetricsStore(EventPushActionsWorkerStore, SQLBaseStore):
+    """Functions to pull various metrics from the DB, for e.g. phone home
+    stats and prometheus metrics.
+    """
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super().__init__(database, db_conn, hs)
+
+        # Collect metrics on the number of forward extremities that exist.
+        # Counter of number of extremities to count
+        self._current_forward_extremities_amount = (
+            Counter()
+        )  # type: typing.Counter[int]
+
+        BucketCollector(
+            "synapse_forward_extremities",
+            lambda: self._current_forward_extremities_amount,
+            buckets=[1, 2, 3, 5, 7, 10, 15, 20, 50, 100, 200, 500, "+Inf"],
+        )
+
+        # Read the extrems every 60 minutes
+        def read_forward_extremities():
+            # run as a background process to make sure that the database transactions
+            # have a logcontext to report to
+            return run_as_background_process(
+                "read_forward_extremities", self._read_forward_extremities
+            )
+
+        hs.get_clock().looping_call(read_forward_extremities, 60 * 60 * 1000)
+
+    async def _read_forward_extremities(self):
+        def fetch(txn):
+            txn.execute(
+                """
+                select count(*) c from event_forward_extremities
+                group by room_id
+                """
+            )
+            return txn.fetchall()
+
+        res = await self.db_pool.runInteraction("read_forward_extremities", fetch)
+        self._current_forward_extremities_amount = Counter([x[0] for x in res])
+
+    @defer.inlineCallbacks
+    def count_daily_messages(self):
+        """
+        Returns an estimate of the number of messages sent in the last day.
+
+        If it has been significantly less or more than one day since the last
+        call to this function, it will return None.
+        """
+
+        def _count_messages(txn):
+            sql = """
+                SELECT COALESCE(COUNT(*), 0) FROM events
+                WHERE type = 'm.room.message'
+                AND stream_ordering > ?
+            """
+            txn.execute(sql, (self.stream_ordering_day_ago,))
+            (count,) = txn.fetchone()
+            return count
+
+        ret = yield self.db_pool.runInteraction("count_messages", _count_messages)
+        return ret
+
+    @defer.inlineCallbacks
+    def count_daily_sent_messages(self):
+        def _count_messages(txn):
+            # This is good enough as if you have silly characters in your own
+            # hostname then thats your own fault.
+            like_clause = "%:" + self.hs.hostname
+
+            sql = """
+                SELECT COALESCE(COUNT(*), 0) FROM events
+                WHERE type = 'm.room.message'
+                    AND sender LIKE ?
+                AND stream_ordering > ?
+            """
+
+            txn.execute(sql, (like_clause, self.stream_ordering_day_ago))
+            (count,) = txn.fetchone()
+            return count
+
+        ret = yield self.db_pool.runInteraction(
+            "count_daily_sent_messages", _count_messages
+        )
+        return ret
+
+    @defer.inlineCallbacks
+    def count_daily_active_rooms(self):
+        def _count(txn):
+            sql = """
+                SELECT COALESCE(COUNT(DISTINCT room_id), 0) FROM events
+                WHERE type = 'm.room.message'
+                AND stream_ordering > ?
+            """
+            txn.execute(sql, (self.stream_ordering_day_ago,))
+            (count,) = txn.fetchone()
+            return count
+
+        ret = yield self.db_pool.runInteraction("count_daily_active_rooms", _count)
+        return ret
diff --git a/synapse/storage/databases/main/monthly_active_users.py b/synapse/storage/databases/main/monthly_active_users.py
new file mode 100644
index 0000000000..02b01d9619
--- /dev/null
+++ b/synapse/storage/databases/main/monthly_active_users.py
@@ -0,0 +1,361 @@
+# -*- coding: utf-8 -*-
+# Copyright 2018 New Vector
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+from typing import List
+
+from twisted.internet import defer
+
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool, make_in_list_sql_clause
+from synapse.util.caches.descriptors import cached
+
+logger = logging.getLogger(__name__)
+
+# Number of msec of granularity to store the monthly_active_user timestamp
+# This means it is not necessary to update the table on every request
+LAST_SEEN_GRANULARITY = 60 * 60 * 1000
+
+
+class MonthlyActiveUsersWorkerStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(MonthlyActiveUsersWorkerStore, self).__init__(database, db_conn, hs)
+        self._clock = hs.get_clock()
+        self.hs = hs
+
+    @cached(num_args=0)
+    def get_monthly_active_count(self):
+        """Generates current count of monthly active users
+
+        Returns:
+            Defered[int]: Number of current monthly active users
+        """
+
+        def _count_users(txn):
+            sql = "SELECT COALESCE(count(*), 0) FROM monthly_active_users"
+            txn.execute(sql)
+            (count,) = txn.fetchone()
+            return count
+
+        return self.db_pool.runInteraction("count_users", _count_users)
+
+    @cached(num_args=0)
+    def get_monthly_active_count_by_service(self):
+        """Generates current count of monthly active users broken down by service.
+        A service is typically an appservice but also includes native matrix users.
+        Since the `monthly_active_users` table is populated from the `user_ips` table
+        `config.track_appservice_user_ips` must be set to `true` for this
+        method to return anything other than native matrix users.
+
+        Returns:
+            Deferred[dict]: dict that includes a mapping between app_service_id
+                and the number of occurrences.
+
+        """
+
+        def _count_users_by_service(txn):
+            sql = """
+                SELECT COALESCE(appservice_id, 'native'), COALESCE(count(*), 0)
+                FROM monthly_active_users
+                LEFT JOIN users ON monthly_active_users.user_id=users.name
+                GROUP BY appservice_id;
+            """
+
+            txn.execute(sql)
+            result = txn.fetchall()
+            return dict(result)
+
+        return self.db_pool.runInteraction(
+            "count_users_by_service", _count_users_by_service
+        )
+
+    async def get_registered_reserved_users(self) -> List[str]:
+        """Of the reserved threepids defined in config, retrieve those that are associated
+        with registered users
+
+        Returns:
+            User IDs of actual users that are reserved
+        """
+        users = []
+
+        for tp in self.hs.config.mau_limits_reserved_threepids[
+            : self.hs.config.max_mau_value
+        ]:
+            user_id = await self.hs.get_datastore().get_user_id_by_threepid(
+                tp["medium"], tp["address"]
+            )
+            if user_id:
+                users.append(user_id)
+
+        return users
+
+    @cached(num_args=1)
+    def user_last_seen_monthly_active(self, user_id):
+        """
+            Checks if a given user is part of the monthly active user group
+            Arguments:
+                user_id (str): user to add/update
+            Return:
+                Deferred[int] : timestamp since last seen, None if never seen
+
+        """
+
+        return self.db_pool.simple_select_one_onecol(
+            table="monthly_active_users",
+            keyvalues={"user_id": user_id},
+            retcol="timestamp",
+            allow_none=True,
+            desc="user_last_seen_monthly_active",
+        )
+
+
+class MonthlyActiveUsersStore(MonthlyActiveUsersWorkerStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(MonthlyActiveUsersStore, self).__init__(database, db_conn, hs)
+
+        self._limit_usage_by_mau = hs.config.limit_usage_by_mau
+        self._mau_stats_only = hs.config.mau_stats_only
+        self._max_mau_value = hs.config.max_mau_value
+
+        # Do not add more reserved users than the total allowable number
+        # cur = LoggingTransaction(
+        self.db_pool.new_transaction(
+            db_conn,
+            "initialise_mau_threepids",
+            [],
+            [],
+            self._initialise_reserved_users,
+            hs.config.mau_limits_reserved_threepids[: self._max_mau_value],
+        )
+
+    def _initialise_reserved_users(self, txn, threepids):
+        """Ensures that reserved threepids are accounted for in the MAU table, should
+        be called on start up.
+
+        Args:
+            txn (cursor):
+            threepids (list[dict]): List of threepid dicts to reserve
+        """
+
+        # XXX what is this function trying to achieve?  It upserts into
+        # monthly_active_users for each *registered* reserved mau user, but why?
+        #
+        #  - shouldn't there already be an entry for each reserved user (at least
+        #    if they have been active recently)?
+        #
+        #  - if it's important that the timestamp is kept up to date, why do we only
+        #    run this at startup?
+
+        for tp in threepids:
+            user_id = self.get_user_id_by_threepid_txn(txn, tp["medium"], tp["address"])
+
+            if user_id:
+                is_support = self.is_support_user_txn(txn, user_id)
+                if not is_support:
+                    # We do this manually here to avoid hitting #6791
+                    self.db_pool.simple_upsert_txn(
+                        txn,
+                        table="monthly_active_users",
+                        keyvalues={"user_id": user_id},
+                        values={"timestamp": int(self._clock.time_msec())},
+                    )
+            else:
+                logger.warning("mau limit reserved threepid %s not found in db" % tp)
+
+    async def reap_monthly_active_users(self):
+        """Cleans out monthly active user table to ensure that no stale
+        entries exist.
+        """
+
+        def _reap_users(txn, reserved_users):
+            """
+            Args:
+                reserved_users (tuple): reserved users to preserve
+            """
+
+            thirty_days_ago = int(self._clock.time_msec()) - (1000 * 60 * 60 * 24 * 30)
+
+            in_clause, in_clause_args = make_in_list_sql_clause(
+                self.database_engine, "user_id", reserved_users
+            )
+
+            txn.execute(
+                "DELETE FROM monthly_active_users WHERE timestamp < ? AND NOT %s"
+                % (in_clause,),
+                [thirty_days_ago] + in_clause_args,
+            )
+
+            if self._limit_usage_by_mau:
+                # If MAU user count still exceeds the MAU threshold, then delete on
+                # a least recently active basis.
+                # Note it is not possible to write this query using OFFSET due to
+                # incompatibilities in how sqlite and postgres support the feature.
+                # Sqlite requires 'LIMIT -1 OFFSET ?', the LIMIT must be present,
+                # while Postgres does not require 'LIMIT', but also does not support
+                # negative LIMIT values. So there is no way to write it that both can
+                # support
+
+                # Limit must be >= 0 for postgres
+                num_of_non_reserved_users_to_remove = max(
+                    self._max_mau_value - len(reserved_users), 0
+                )
+
+                # It is important to filter reserved users twice to guard
+                # against the case where the reserved user is present in the
+                # SELECT, meaning that a legitimate mau is deleted.
+                sql = """
+                    DELETE FROM monthly_active_users
+                    WHERE user_id NOT IN (
+                        SELECT user_id FROM monthly_active_users
+                        WHERE NOT %s
+                        ORDER BY timestamp DESC
+                        LIMIT ?
+                    )
+                    AND NOT %s
+                """ % (
+                    in_clause,
+                    in_clause,
+                )
+
+                query_args = (
+                    in_clause_args
+                    + [num_of_non_reserved_users_to_remove]
+                    + in_clause_args
+                )
+                txn.execute(sql, query_args)
+
+            # It seems poor to invalidate the whole cache. Postgres supports
+            # 'Returning' which would allow me to invalidate only the
+            # specific users, but sqlite has no way to do this and instead
+            # I would need to SELECT and the DELETE which without locking
+            # is racy.
+            # Have resolved to invalidate the whole cache for now and do
+            # something about it if and when the perf becomes significant
+            self._invalidate_all_cache_and_stream(
+                txn, self.user_last_seen_monthly_active
+            )
+            self._invalidate_cache_and_stream(txn, self.get_monthly_active_count, ())
+
+        reserved_users = await self.get_registered_reserved_users()
+        await self.db_pool.runInteraction(
+            "reap_monthly_active_users", _reap_users, reserved_users
+        )
+
+    @defer.inlineCallbacks
+    def upsert_monthly_active_user(self, user_id):
+        """Updates or inserts the user into the monthly active user table, which
+        is used to track the current MAU usage of the server
+
+        Args:
+            user_id (str): user to add/update
+
+        Returns:
+            Deferred
+        """
+        # Support user never to be included in MAU stats. Note I can't easily call this
+        # from upsert_monthly_active_user_txn because then I need a _txn form of
+        # is_support_user which is complicated because I want to cache the result.
+        # Therefore I call it here and ignore the case where
+        # upsert_monthly_active_user_txn is called directly from
+        # _initialise_reserved_users reasoning that it would be very strange to
+        #  include a support user in this context.
+
+        is_support = yield self.is_support_user(user_id)
+        if is_support:
+            return
+
+        yield self.db_pool.runInteraction(
+            "upsert_monthly_active_user", self.upsert_monthly_active_user_txn, user_id
+        )
+
+    def upsert_monthly_active_user_txn(self, txn, user_id):
+        """Updates or inserts monthly active user member
+
+        We consciously do not call is_support_txn from this method because it
+        is not possible to cache the response. is_support_txn will be false in
+        almost all cases, so it seems reasonable to call it only for
+        upsert_monthly_active_user and to call is_support_txn manually
+        for cases where upsert_monthly_active_user_txn is called directly,
+        like _initialise_reserved_users
+
+        In short, don't call this method with support users. (Support users
+        should not appear in the MAU stats).
+
+        Args:
+            txn (cursor):
+            user_id (str): user to add/update
+
+        Returns:
+            bool: True if a new entry was created, False if an
+            existing one was updated.
+        """
+
+        # Am consciously deciding to lock the table on the basis that is ought
+        # never be a big table and alternative approaches (batching multiple
+        # upserts into a single txn) introduced a lot of extra complexity.
+        # See https://github.com/matrix-org/synapse/issues/3854 for more
+        is_insert = self.db_pool.simple_upsert_txn(
+            txn,
+            table="monthly_active_users",
+            keyvalues={"user_id": user_id},
+            values={"timestamp": int(self._clock.time_msec())},
+        )
+
+        self._invalidate_cache_and_stream(txn, self.get_monthly_active_count, ())
+        self._invalidate_cache_and_stream(
+            txn, self.get_monthly_active_count_by_service, ()
+        )
+        self._invalidate_cache_and_stream(
+            txn, self.user_last_seen_monthly_active, (user_id,)
+        )
+
+        return is_insert
+
+    @defer.inlineCallbacks
+    def populate_monthly_active_users(self, user_id):
+        """Checks on the state of monthly active user limits and optionally
+        add the user to the monthly active tables
+
+        Args:
+            user_id(str): the user_id to query
+        """
+        if self._limit_usage_by_mau or self._mau_stats_only:
+            # Trial users and guests should not be included as part of MAU group
+            is_guest = yield self.is_guest(user_id)
+            if is_guest:
+                return
+            is_trial = yield self.is_trial_user(user_id)
+            if is_trial:
+                return
+
+            last_seen_timestamp = yield self.user_last_seen_monthly_active(user_id)
+            now = self.hs.get_clock().time_msec()
+
+            # We want to reduce to the total number of db writes, and are happy
+            # to trade accuracy of timestamp in order to lighten load. This means
+            # We always insert new users (where MAU threshold has not been reached),
+            # but only update if we have not previously seen the user for
+            # LAST_SEEN_GRANULARITY ms
+            if last_seen_timestamp is None:
+                # In the case where mau_stats_only is True and limit_usage_by_mau is
+                # False, there is no point in checking get_monthly_active_count - it
+                # adds no value and will break the logic if max_mau_value is exceeded.
+                if not self._limit_usage_by_mau:
+                    yield self.upsert_monthly_active_user(user_id)
+                else:
+                    count = yield self.get_monthly_active_count()
+                    if count < self._max_mau_value:
+                        yield self.upsert_monthly_active_user(user_id)
+            elif now - last_seen_timestamp > LAST_SEEN_GRANULARITY:
+                yield self.upsert_monthly_active_user(user_id)
diff --git a/synapse/storage/databases/main/openid.py b/synapse/storage/databases/main/openid.py
new file mode 100644
index 0000000000..dcd1ff911a
--- /dev/null
+++ b/synapse/storage/databases/main/openid.py
@@ -0,0 +1,33 @@
+from synapse.storage._base import SQLBaseStore
+
+
+class OpenIdStore(SQLBaseStore):
+    def insert_open_id_token(self, token, ts_valid_until_ms, user_id):
+        return self.db_pool.simple_insert(
+            table="open_id_tokens",
+            values={
+                "token": token,
+                "ts_valid_until_ms": ts_valid_until_ms,
+                "user_id": user_id,
+            },
+            desc="insert_open_id_token",
+        )
+
+    def get_user_id_for_open_id_token(self, token, ts_now_ms):
+        def get_user_id_for_token_txn(txn):
+            sql = (
+                "SELECT user_id FROM open_id_tokens"
+                " WHERE token = ? AND ? <= ts_valid_until_ms"
+            )
+
+            txn.execute(sql, (token, ts_now_ms))
+
+            rows = txn.fetchall()
+            if not rows:
+                return None
+            else:
+                return rows[0][0]
+
+        return self.db_pool.runInteraction(
+            "get_user_id_for_token", get_user_id_for_token_txn
+        )
diff --git a/synapse/storage/databases/main/presence.py b/synapse/storage/databases/main/presence.py
new file mode 100644
index 0000000000..99e66dc6e9
--- /dev/null
+++ b/synapse/storage/databases/main/presence.py
@@ -0,0 +1,186 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from typing import List, Tuple
+
+from twisted.internet import defer
+
+from synapse.storage._base import SQLBaseStore, make_in_list_sql_clause
+from synapse.storage.presence import UserPresenceState
+from synapse.util.caches.descriptors import cached, cachedList
+from synapse.util.iterutils import batch_iter
+
+
+class PresenceStore(SQLBaseStore):
+    @defer.inlineCallbacks
+    def update_presence(self, presence_states):
+        stream_ordering_manager = self._presence_id_gen.get_next_mult(
+            len(presence_states)
+        )
+
+        with stream_ordering_manager as stream_orderings:
+            yield self.db_pool.runInteraction(
+                "update_presence",
+                self._update_presence_txn,
+                stream_orderings,
+                presence_states,
+            )
+
+        return stream_orderings[-1], self._presence_id_gen.get_current_token()
+
+    def _update_presence_txn(self, txn, stream_orderings, presence_states):
+        for stream_id, state in zip(stream_orderings, presence_states):
+            txn.call_after(
+                self.presence_stream_cache.entity_has_changed, state.user_id, stream_id
+            )
+            txn.call_after(self._get_presence_for_user.invalidate, (state.user_id,))
+
+        # Actually insert new rows
+        self.db_pool.simple_insert_many_txn(
+            txn,
+            table="presence_stream",
+            values=[
+                {
+                    "stream_id": stream_id,
+                    "user_id": state.user_id,
+                    "state": state.state,
+                    "last_active_ts": state.last_active_ts,
+                    "last_federation_update_ts": state.last_federation_update_ts,
+                    "last_user_sync_ts": state.last_user_sync_ts,
+                    "status_msg": state.status_msg,
+                    "currently_active": state.currently_active,
+                }
+                for stream_id, state in zip(stream_orderings, presence_states)
+            ],
+        )
+
+        # Delete old rows to stop database from getting really big
+        sql = "DELETE FROM presence_stream WHERE stream_id < ? AND "
+
+        for states in batch_iter(presence_states, 50):
+            clause, args = make_in_list_sql_clause(
+                self.database_engine, "user_id", [s.user_id for s in states]
+            )
+            txn.execute(sql + clause, [stream_id] + list(args))
+
+    async def get_all_presence_updates(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, list]], int, bool]:
+        """Get updates for presence replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_presence_updates_txn(txn):
+            sql = """
+                SELECT stream_id, user_id, state, last_active_ts,
+                    last_federation_update_ts, last_user_sync_ts,
+                    status_msg,
+                currently_active
+                FROM presence_stream
+                WHERE ? < stream_id AND stream_id <= ?
+                ORDER BY stream_id ASC
+                LIMIT ?
+            """
+            txn.execute(sql, (last_id, current_id, limit))
+            updates = [(row[0], row[1:]) for row in txn]
+
+            upper_bound = current_id
+            limited = False
+            if len(updates) >= limit:
+                upper_bound = updates[-1][0]
+                limited = True
+
+            return updates, upper_bound, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_presence_updates", get_all_presence_updates_txn
+        )
+
+    @cached()
+    def _get_presence_for_user(self, user_id):
+        raise NotImplementedError()
+
+    @cachedList(
+        cached_method_name="_get_presence_for_user",
+        list_name="user_ids",
+        num_args=1,
+        inlineCallbacks=True,
+    )
+    def get_presence_for_users(self, user_ids):
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="presence_stream",
+            column="user_id",
+            iterable=user_ids,
+            keyvalues={},
+            retcols=(
+                "user_id",
+                "state",
+                "last_active_ts",
+                "last_federation_update_ts",
+                "last_user_sync_ts",
+                "status_msg",
+                "currently_active",
+            ),
+            desc="get_presence_for_users",
+        )
+
+        for row in rows:
+            row["currently_active"] = bool(row["currently_active"])
+
+        return {row["user_id"]: UserPresenceState(**row) for row in rows}
+
+    def get_current_presence_token(self):
+        return self._presence_id_gen.get_current_token()
+
+    def allow_presence_visible(self, observed_localpart, observer_userid):
+        return self.db_pool.simple_insert(
+            table="presence_allow_inbound",
+            values={
+                "observed_user_id": observed_localpart,
+                "observer_user_id": observer_userid,
+            },
+            desc="allow_presence_visible",
+            or_ignore=True,
+        )
+
+    def disallow_presence_visible(self, observed_localpart, observer_userid):
+        return self.db_pool.simple_delete_one(
+            table="presence_allow_inbound",
+            keyvalues={
+                "observed_user_id": observed_localpart,
+                "observer_user_id": observer_userid,
+            },
+            desc="disallow_presence_visible",
+        )
diff --git a/synapse/storage/databases/main/profile.py b/synapse/storage/databases/main/profile.py
new file mode 100644
index 0000000000..4a4f2cb385
--- /dev/null
+++ b/synapse/storage/databases/main/profile.py
@@ -0,0 +1,178 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from twisted.internet import defer
+
+from synapse.api.errors import StoreError
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.databases.main.roommember import ProfileInfo
+
+
+class ProfileWorkerStore(SQLBaseStore):
+    @defer.inlineCallbacks
+    def get_profileinfo(self, user_localpart):
+        try:
+            profile = yield self.db_pool.simple_select_one(
+                table="profiles",
+                keyvalues={"user_id": user_localpart},
+                retcols=("displayname", "avatar_url"),
+                desc="get_profileinfo",
+            )
+        except StoreError as e:
+            if e.code == 404:
+                # no match
+                return ProfileInfo(None, None)
+            else:
+                raise
+
+        return ProfileInfo(
+            avatar_url=profile["avatar_url"], display_name=profile["displayname"]
+        )
+
+    def get_profile_displayname(self, user_localpart):
+        return self.db_pool.simple_select_one_onecol(
+            table="profiles",
+            keyvalues={"user_id": user_localpart},
+            retcol="displayname",
+            desc="get_profile_displayname",
+        )
+
+    def get_profile_avatar_url(self, user_localpart):
+        return self.db_pool.simple_select_one_onecol(
+            table="profiles",
+            keyvalues={"user_id": user_localpart},
+            retcol="avatar_url",
+            desc="get_profile_avatar_url",
+        )
+
+    def get_from_remote_profile_cache(self, user_id):
+        return self.db_pool.simple_select_one(
+            table="remote_profile_cache",
+            keyvalues={"user_id": user_id},
+            retcols=("displayname", "avatar_url"),
+            allow_none=True,
+            desc="get_from_remote_profile_cache",
+        )
+
+    def create_profile(self, user_localpart):
+        return self.db_pool.simple_insert(
+            table="profiles", values={"user_id": user_localpart}, desc="create_profile"
+        )
+
+    def set_profile_displayname(self, user_localpart, new_displayname):
+        return self.db_pool.simple_update_one(
+            table="profiles",
+            keyvalues={"user_id": user_localpart},
+            updatevalues={"displayname": new_displayname},
+            desc="set_profile_displayname",
+        )
+
+    def set_profile_avatar_url(self, user_localpart, new_avatar_url):
+        return self.db_pool.simple_update_one(
+            table="profiles",
+            keyvalues={"user_id": user_localpart},
+            updatevalues={"avatar_url": new_avatar_url},
+            desc="set_profile_avatar_url",
+        )
+
+
+class ProfileStore(ProfileWorkerStore):
+    def add_remote_profile_cache(self, user_id, displayname, avatar_url):
+        """Ensure we are caching the remote user's profiles.
+
+        This should only be called when `is_subscribed_remote_profile_for_user`
+        would return true for the user.
+        """
+        return self.db_pool.simple_upsert(
+            table="remote_profile_cache",
+            keyvalues={"user_id": user_id},
+            values={
+                "displayname": displayname,
+                "avatar_url": avatar_url,
+                "last_check": self._clock.time_msec(),
+            },
+            desc="add_remote_profile_cache",
+        )
+
+    def update_remote_profile_cache(self, user_id, displayname, avatar_url):
+        return self.db_pool.simple_update(
+            table="remote_profile_cache",
+            keyvalues={"user_id": user_id},
+            updatevalues={
+                "displayname": displayname,
+                "avatar_url": avatar_url,
+                "last_check": self._clock.time_msec(),
+            },
+            desc="update_remote_profile_cache",
+        )
+
+    @defer.inlineCallbacks
+    def maybe_delete_remote_profile_cache(self, user_id):
+        """Check if we still care about the remote user's profile, and if we
+        don't then remove their profile from the cache
+        """
+        subscribed = yield self.is_subscribed_remote_profile_for_user(user_id)
+        if not subscribed:
+            yield self.db_pool.simple_delete(
+                table="remote_profile_cache",
+                keyvalues={"user_id": user_id},
+                desc="delete_remote_profile_cache",
+            )
+
+    def get_remote_profile_cache_entries_that_expire(self, last_checked):
+        """Get all users who haven't been checked since `last_checked`
+        """
+
+        def _get_remote_profile_cache_entries_that_expire_txn(txn):
+            sql = """
+                SELECT user_id, displayname, avatar_url
+                FROM remote_profile_cache
+                WHERE last_check < ?
+            """
+
+            txn.execute(sql, (last_checked,))
+
+            return self.db_pool.cursor_to_dict(txn)
+
+        return self.db_pool.runInteraction(
+            "get_remote_profile_cache_entries_that_expire",
+            _get_remote_profile_cache_entries_that_expire_txn,
+        )
+
+    @defer.inlineCallbacks
+    def is_subscribed_remote_profile_for_user(self, user_id):
+        """Check whether we are interested in a remote user's profile.
+        """
+        res = yield self.db_pool.simple_select_one_onecol(
+            table="group_users",
+            keyvalues={"user_id": user_id},
+            retcol="user_id",
+            allow_none=True,
+            desc="should_update_remote_profile_cache_for_user",
+        )
+
+        if res:
+            return True
+
+        res = yield self.db_pool.simple_select_one_onecol(
+            table="group_invites",
+            keyvalues={"user_id": user_id},
+            retcol="user_id",
+            allow_none=True,
+            desc="should_update_remote_profile_cache_for_user",
+        )
+
+        if res:
+            return True
diff --git a/synapse/storage/databases/main/purge_events.py b/synapse/storage/databases/main/purge_events.py
new file mode 100644
index 0000000000..3526b6fd66
--- /dev/null
+++ b/synapse/storage/databases/main/purge_events.py
@@ -0,0 +1,400 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from typing import Any, Tuple
+
+from synapse.api.errors import SynapseError
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.databases.main.state import StateGroupWorkerStore
+from synapse.types import RoomStreamToken
+
+logger = logging.getLogger(__name__)
+
+
+class PurgeEventsStore(StateGroupWorkerStore, SQLBaseStore):
+    def purge_history(self, room_id, token, delete_local_events):
+        """Deletes room history before a certain point
+
+        Args:
+            room_id (str):
+
+            token (str): A topological token to delete events before
+
+            delete_local_events (bool):
+                if True, we will delete local events as well as remote ones
+                (instead of just marking them as outliers and deleting their
+                state groups).
+
+        Returns:
+            Deferred[set[int]]: The set of state groups that are referenced by
+            deleted events.
+        """
+
+        return self.db_pool.runInteraction(
+            "purge_history",
+            self._purge_history_txn,
+            room_id,
+            token,
+            delete_local_events,
+        )
+
+    def _purge_history_txn(self, txn, room_id, token_str, delete_local_events):
+        token = RoomStreamToken.parse(token_str)
+
+        # Tables that should be pruned:
+        #     event_auth
+        #     event_backward_extremities
+        #     event_edges
+        #     event_forward_extremities
+        #     event_json
+        #     event_push_actions
+        #     event_reference_hashes
+        #     event_relations
+        #     event_search
+        #     event_to_state_groups
+        #     events
+        #     rejections
+        #     room_depth
+        #     state_groups
+        #     state_groups_state
+
+        # we will build a temporary table listing the events so that we don't
+        # have to keep shovelling the list back and forth across the
+        # connection. Annoyingly the python sqlite driver commits the
+        # transaction on CREATE, so let's do this first.
+        #
+        # furthermore, we might already have the table from a previous (failed)
+        # purge attempt, so let's drop the table first.
+
+        txn.execute("DROP TABLE IF EXISTS events_to_purge")
+
+        txn.execute(
+            "CREATE TEMPORARY TABLE events_to_purge ("
+            "    event_id TEXT NOT NULL,"
+            "    should_delete BOOLEAN NOT NULL"
+            ")"
+        )
+
+        # First ensure that we're not about to delete all the forward extremeties
+        txn.execute(
+            "SELECT e.event_id, e.depth FROM events as e "
+            "INNER JOIN event_forward_extremities as f "
+            "ON e.event_id = f.event_id "
+            "AND e.room_id = f.room_id "
+            "WHERE f.room_id = ?",
+            (room_id,),
+        )
+        rows = txn.fetchall()
+        max_depth = max(row[1] for row in rows)
+
+        if max_depth < token.topological:
+            # We need to ensure we don't delete all the events from the database
+            # otherwise we wouldn't be able to send any events (due to not
+            # having any backwards extremeties)
+            raise SynapseError(
+                400, "topological_ordering is greater than forward extremeties"
+            )
+
+        logger.info("[purge] looking for events to delete")
+
+        should_delete_expr = "state_key IS NULL"
+        should_delete_params = ()  # type: Tuple[Any, ...]
+        if not delete_local_events:
+            should_delete_expr += " AND event_id NOT LIKE ?"
+
+            # We include the parameter twice since we use the expression twice
+            should_delete_params += ("%:" + self.hs.hostname, "%:" + self.hs.hostname)
+
+        should_delete_params += (room_id, token.topological)
+
+        # Note that we insert events that are outliers and aren't going to be
+        # deleted, as nothing will happen to them.
+        txn.execute(
+            "INSERT INTO events_to_purge"
+            " SELECT event_id, %s"
+            " FROM events AS e LEFT JOIN state_events USING (event_id)"
+            " WHERE (NOT outlier OR (%s)) AND e.room_id = ? AND topological_ordering < ?"
+            % (should_delete_expr, should_delete_expr),
+            should_delete_params,
+        )
+
+        # We create the indices *after* insertion as that's a lot faster.
+
+        # create an index on should_delete because later we'll be looking for
+        # the should_delete / shouldn't_delete subsets
+        txn.execute(
+            "CREATE INDEX events_to_purge_should_delete"
+            " ON events_to_purge(should_delete)"
+        )
+
+        # We do joins against events_to_purge for e.g. calculating state
+        # groups to purge, etc., so lets make an index.
+        txn.execute("CREATE INDEX events_to_purge_id ON events_to_purge(event_id)")
+
+        txn.execute("SELECT event_id, should_delete FROM events_to_purge")
+        event_rows = txn.fetchall()
+        logger.info(
+            "[purge] found %i events before cutoff, of which %i can be deleted",
+            len(event_rows),
+            sum(1 for e in event_rows if e[1]),
+        )
+
+        logger.info("[purge] Finding new backward extremities")
+
+        # We calculate the new entries for the backward extremeties by finding
+        # events to be purged that are pointed to by events we're not going to
+        # purge.
+        txn.execute(
+            "SELECT DISTINCT e.event_id FROM events_to_purge AS e"
+            " INNER JOIN event_edges AS ed ON e.event_id = ed.prev_event_id"
+            " LEFT JOIN events_to_purge AS ep2 ON ed.event_id = ep2.event_id"
+            " WHERE ep2.event_id IS NULL"
+        )
+        new_backwards_extrems = txn.fetchall()
+
+        logger.info("[purge] replacing backward extremities: %r", new_backwards_extrems)
+
+        txn.execute(
+            "DELETE FROM event_backward_extremities WHERE room_id = ?", (room_id,)
+        )
+
+        # Update backward extremeties
+        txn.executemany(
+            "INSERT INTO event_backward_extremities (room_id, event_id)"
+            " VALUES (?, ?)",
+            [(room_id, event_id) for event_id, in new_backwards_extrems],
+        )
+
+        logger.info("[purge] finding state groups referenced by deleted events")
+
+        # Get all state groups that are referenced by events that are to be
+        # deleted.
+        txn.execute(
+            """
+            SELECT DISTINCT state_group FROM events_to_purge
+            INNER JOIN event_to_state_groups USING (event_id)
+        """
+        )
+
+        referenced_state_groups = {sg for sg, in txn}
+        logger.info(
+            "[purge] found %i referenced state groups", len(referenced_state_groups)
+        )
+
+        logger.info("[purge] removing events from event_to_state_groups")
+        txn.execute(
+            "DELETE FROM event_to_state_groups "
+            "WHERE event_id IN (SELECT event_id from events_to_purge)"
+        )
+        for event_id, _ in event_rows:
+            txn.call_after(self._get_state_group_for_event.invalidate, (event_id,))
+
+        # Delete all remote non-state events
+        for table in (
+            "events",
+            "event_json",
+            "event_auth",
+            "event_edges",
+            "event_forward_extremities",
+            "event_reference_hashes",
+            "event_relations",
+            "event_search",
+            "rejections",
+        ):
+            logger.info("[purge] removing events from %s", table)
+
+            txn.execute(
+                "DELETE FROM %s WHERE event_id IN ("
+                "    SELECT event_id FROM events_to_purge WHERE should_delete"
+                ")" % (table,)
+            )
+
+        # event_push_actions lacks an index on event_id, and has one on
+        # (room_id, event_id) instead.
+        for table in ("event_push_actions",):
+            logger.info("[purge] removing events from %s", table)
+
+            txn.execute(
+                "DELETE FROM %s WHERE room_id = ? AND event_id IN ("
+                "    SELECT event_id FROM events_to_purge WHERE should_delete"
+                ")" % (table,),
+                (room_id,),
+            )
+
+        # Mark all state and own events as outliers
+        logger.info("[purge] marking remaining events as outliers")
+        txn.execute(
+            "UPDATE events SET outlier = ?"
+            " WHERE event_id IN ("
+            "    SELECT event_id FROM events_to_purge "
+            "    WHERE NOT should_delete"
+            ")",
+            (True,),
+        )
+
+        # synapse tries to take out an exclusive lock on room_depth whenever it
+        # persists events (because upsert), and once we run this update, we
+        # will block that for the rest of our transaction.
+        #
+        # So, let's stick it at the end so that we don't block event
+        # persistence.
+        #
+        # We do this by calculating the minimum depth of the backwards
+        # extremities. However, the events in event_backward_extremities
+        # are ones we don't have yet so we need to look at the events that
+        # point to it via event_edges table.
+        txn.execute(
+            """
+            SELECT COALESCE(MIN(depth), 0)
+            FROM event_backward_extremities AS eb
+            INNER JOIN event_edges AS eg ON eg.prev_event_id = eb.event_id
+            INNER JOIN events AS e ON e.event_id = eg.event_id
+            WHERE eb.room_id = ?
+        """,
+            (room_id,),
+        )
+        (min_depth,) = txn.fetchone()
+
+        logger.info("[purge] updating room_depth to %d", min_depth)
+
+        txn.execute(
+            "UPDATE room_depth SET min_depth = ? WHERE room_id = ?",
+            (min_depth, room_id),
+        )
+
+        # finally, drop the temp table. this will commit the txn in sqlite,
+        # so make sure to keep this actually last.
+        txn.execute("DROP TABLE events_to_purge")
+
+        logger.info("[purge] done")
+
+        return referenced_state_groups
+
+    def purge_room(self, room_id):
+        """Deletes all record of a room
+
+        Args:
+            room_id (str)
+
+        Returns:
+            Deferred[List[int]]: The list of state groups to delete.
+        """
+
+        return self.db_pool.runInteraction("purge_room", self._purge_room_txn, room_id)
+
+    def _purge_room_txn(self, txn, room_id):
+        # First we fetch all the state groups that should be deleted, before
+        # we delete that information.
+        txn.execute(
+            """
+                SELECT DISTINCT state_group FROM events
+                INNER JOIN event_to_state_groups USING(event_id)
+                WHERE events.room_id = ?
+            """,
+            (room_id,),
+        )
+
+        state_groups = [row[0] for row in txn]
+
+        # Now we delete tables which lack an index on room_id but have one on event_id
+        for table in (
+            "event_auth",
+            "event_edges",
+            "event_push_actions_staging",
+            "event_reference_hashes",
+            "event_relations",
+            "event_to_state_groups",
+            "redactions",
+            "rejections",
+            "state_events",
+        ):
+            logger.info("[purge] removing %s from %s", room_id, table)
+
+            txn.execute(
+                """
+                DELETE FROM %s WHERE event_id IN (
+                  SELECT event_id FROM events WHERE room_id=?
+                )
+                """
+                % (table,),
+                (room_id,),
+            )
+
+        # and finally, the tables with an index on room_id (or no useful index)
+        for table in (
+            "current_state_events",
+            "event_backward_extremities",
+            "event_forward_extremities",
+            "event_json",
+            "event_push_actions",
+            "event_search",
+            "events",
+            "group_rooms",
+            "public_room_list_stream",
+            "receipts_graph",
+            "receipts_linearized",
+            "room_aliases",
+            "room_depth",
+            "room_memberships",
+            "room_stats_state",
+            "room_stats_current",
+            "room_stats_historical",
+            "room_stats_earliest_token",
+            "rooms",
+            "stream_ordering_to_exterm",
+            "users_in_public_rooms",
+            "users_who_share_private_rooms",
+            # no useful index, but let's clear them anyway
+            "appservice_room_list",
+            "e2e_room_keys",
+            "event_push_summary",
+            "pusher_throttle",
+            "group_summary_rooms",
+            "room_account_data",
+            "room_tags",
+            "local_current_membership",
+        ):
+            logger.info("[purge] removing %s from %s", room_id, table)
+            txn.execute("DELETE FROM %s WHERE room_id=?" % (table,), (room_id,))
+
+        # Other tables we do NOT need to clear out:
+        #
+        #  - blocked_rooms
+        #    This is important, to make sure that we don't accidentally rejoin a blocked
+        #    room after it was purged
+        #
+        #  - user_directory
+        #    This has a room_id column, but it is unused
+        #
+
+        # Other tables that we might want to consider clearing out include:
+        #
+        #  - event_reports
+        #       Given that these are intended for abuse management my initial
+        #       inclination is to leave them in place.
+        #
+        #  - current_state_delta_stream
+        #  - ex_outlier_stream
+        #  - room_tags_revisions
+        #       The problem with these is that they are largeish and there is no room_id
+        #       index on them. In any case we should be clearing out 'stream' tables
+        #       periodically anyway (#5888)
+
+        # TODO: we could probably usefully do a bunch of cache invalidation here
+
+        logger.info("[purge] done")
+
+        return state_groups
diff --git a/synapse/storage/databases/main/push_rule.py b/synapse/storage/databases/main/push_rule.py
new file mode 100644
index 0000000000..5fd899326a
--- /dev/null
+++ b/synapse/storage/databases/main/push_rule.py
@@ -0,0 +1,767 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import abc
+import logging
+from typing import List, Tuple, Union
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.push.baserules import list_with_base_rules
+from synapse.replication.slave.storage._slaved_id_tracker import SlavedIdTracker
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.appservice import ApplicationServiceWorkerStore
+from synapse.storage.databases.main.events_worker import EventsWorkerStore
+from synapse.storage.databases.main.pusher import PusherWorkerStore
+from synapse.storage.databases.main.receipts import ReceiptsWorkerStore
+from synapse.storage.databases.main.roommember import RoomMemberWorkerStore
+from synapse.storage.push_rule import InconsistentRuleException, RuleNotFoundException
+from synapse.storage.util.id_generators import ChainedIdGenerator
+from synapse.util.caches.descriptors import cachedInlineCallbacks, cachedList
+from synapse.util.caches.stream_change_cache import StreamChangeCache
+
+logger = logging.getLogger(__name__)
+
+
+def _load_rules(rawrules, enabled_map, use_new_defaults=False):
+    ruleslist = []
+    for rawrule in rawrules:
+        rule = dict(rawrule)
+        rule["conditions"] = db_to_json(rawrule["conditions"])
+        rule["actions"] = db_to_json(rawrule["actions"])
+        rule["default"] = False
+        ruleslist.append(rule)
+
+    # We're going to be mutating this a lot, so do a deep copy
+    rules = list(list_with_base_rules(ruleslist, use_new_defaults))
+
+    for i, rule in enumerate(rules):
+        rule_id = rule["rule_id"]
+        if rule_id in enabled_map:
+            if rule.get("enabled", True) != bool(enabled_map[rule_id]):
+                # Rules are cached across users.
+                rule = dict(rule)
+                rule["enabled"] = bool(enabled_map[rule_id])
+                rules[i] = rule
+
+    return rules
+
+
+class PushRulesWorkerStore(
+    ApplicationServiceWorkerStore,
+    ReceiptsWorkerStore,
+    PusherWorkerStore,
+    RoomMemberWorkerStore,
+    EventsWorkerStore,
+    SQLBaseStore,
+):
+    """This is an abstract base class where subclasses must implement
+    `get_max_push_rules_stream_id` which can be called in the initializer.
+    """
+
+    # This ABCMeta metaclass ensures that we cannot be instantiated without
+    # the abstract methods being implemented.
+    __metaclass__ = abc.ABCMeta
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(PushRulesWorkerStore, self).__init__(database, db_conn, hs)
+
+        if hs.config.worker.worker_app is None:
+            self._push_rules_stream_id_gen = ChainedIdGenerator(
+                self._stream_id_gen, db_conn, "push_rules_stream", "stream_id"
+            )  # type: Union[ChainedIdGenerator, SlavedIdTracker]
+        else:
+            self._push_rules_stream_id_gen = SlavedIdTracker(
+                db_conn, "push_rules_stream", "stream_id"
+            )
+
+        push_rules_prefill, push_rules_id = self.db_pool.get_cache_dict(
+            db_conn,
+            "push_rules_stream",
+            entity_column="user_id",
+            stream_column="stream_id",
+            max_value=self.get_max_push_rules_stream_id(),
+        )
+
+        self.push_rules_stream_cache = StreamChangeCache(
+            "PushRulesStreamChangeCache",
+            push_rules_id,
+            prefilled_cache=push_rules_prefill,
+        )
+
+        self._users_new_default_push_rules = hs.config.users_new_default_push_rules
+
+    @abc.abstractmethod
+    def get_max_push_rules_stream_id(self):
+        """Get the position of the push rules stream.
+
+        Returns:
+            int
+        """
+        raise NotImplementedError()
+
+    @cachedInlineCallbacks(max_entries=5000)
+    def get_push_rules_for_user(self, user_id):
+        rows = yield self.db_pool.simple_select_list(
+            table="push_rules",
+            keyvalues={"user_name": user_id},
+            retcols=(
+                "user_name",
+                "rule_id",
+                "priority_class",
+                "priority",
+                "conditions",
+                "actions",
+            ),
+            desc="get_push_rules_enabled_for_user",
+        )
+
+        rows.sort(key=lambda row: (-int(row["priority_class"]), -int(row["priority"])))
+
+        enabled_map = yield self.get_push_rules_enabled_for_user(user_id)
+
+        use_new_defaults = user_id in self._users_new_default_push_rules
+
+        rules = _load_rules(rows, enabled_map, use_new_defaults)
+
+        return rules
+
+    @cachedInlineCallbacks(max_entries=5000)
+    def get_push_rules_enabled_for_user(self, user_id):
+        results = yield self.db_pool.simple_select_list(
+            table="push_rules_enable",
+            keyvalues={"user_name": user_id},
+            retcols=("user_name", "rule_id", "enabled"),
+            desc="get_push_rules_enabled_for_user",
+        )
+        return {r["rule_id"]: False if r["enabled"] == 0 else True for r in results}
+
+    def have_push_rules_changed_for_user(self, user_id, last_id):
+        if not self.push_rules_stream_cache.has_entity_changed(user_id, last_id):
+            return defer.succeed(False)
+        else:
+
+            def have_push_rules_changed_txn(txn):
+                sql = (
+                    "SELECT COUNT(stream_id) FROM push_rules_stream"
+                    " WHERE user_id = ? AND ? < stream_id"
+                )
+                txn.execute(sql, (user_id, last_id))
+                (count,) = txn.fetchone()
+                return bool(count)
+
+            return self.db_pool.runInteraction(
+                "have_push_rules_changed", have_push_rules_changed_txn
+            )
+
+    @cachedList(
+        cached_method_name="get_push_rules_for_user",
+        list_name="user_ids",
+        num_args=1,
+        inlineCallbacks=True,
+    )
+    def bulk_get_push_rules(self, user_ids):
+        if not user_ids:
+            return {}
+
+        results = {user_id: [] for user_id in user_ids}
+
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="push_rules",
+            column="user_name",
+            iterable=user_ids,
+            retcols=("*",),
+            desc="bulk_get_push_rules",
+        )
+
+        rows.sort(key=lambda row: (-int(row["priority_class"]), -int(row["priority"])))
+
+        for row in rows:
+            results.setdefault(row["user_name"], []).append(row)
+
+        enabled_map_by_user = yield self.bulk_get_push_rules_enabled(user_ids)
+
+        for user_id, rules in results.items():
+            use_new_defaults = user_id in self._users_new_default_push_rules
+
+            results[user_id] = _load_rules(
+                rules, enabled_map_by_user.get(user_id, {}), use_new_defaults,
+            )
+
+        return results
+
+    @defer.inlineCallbacks
+    def copy_push_rule_from_room_to_room(self, new_room_id, user_id, rule):
+        """Copy a single push rule from one room to another for a specific user.
+
+        Args:
+            new_room_id (str): ID of the new room.
+            user_id (str): ID of user the push rule belongs to.
+            rule (Dict): A push rule.
+        """
+        # Create new rule id
+        rule_id_scope = "/".join(rule["rule_id"].split("/")[:-1])
+        new_rule_id = rule_id_scope + "/" + new_room_id
+
+        # Change room id in each condition
+        for condition in rule.get("conditions", []):
+            if condition.get("key") == "room_id":
+                condition["pattern"] = new_room_id
+
+        # Add the rule for the new room
+        yield self.add_push_rule(
+            user_id=user_id,
+            rule_id=new_rule_id,
+            priority_class=rule["priority_class"],
+            conditions=rule["conditions"],
+            actions=rule["actions"],
+        )
+
+    @defer.inlineCallbacks
+    def copy_push_rules_from_room_to_room_for_user(
+        self, old_room_id, new_room_id, user_id
+    ):
+        """Copy all of the push rules from one room to another for a specific
+        user.
+
+        Args:
+            old_room_id (str): ID of the old room.
+            new_room_id (str): ID of the new room.
+            user_id (str): ID of user to copy push rules for.
+        """
+        # Retrieve push rules for this user
+        user_push_rules = yield self.get_push_rules_for_user(user_id)
+
+        # Get rules relating to the old room and copy them to the new room
+        for rule in user_push_rules:
+            conditions = rule.get("conditions", [])
+            if any(
+                (c.get("key") == "room_id" and c.get("pattern") == old_room_id)
+                for c in conditions
+            ):
+                yield self.copy_push_rule_from_room_to_room(new_room_id, user_id, rule)
+
+    @defer.inlineCallbacks
+    def bulk_get_push_rules_for_room(self, event, context):
+        state_group = context.state_group
+        if not state_group:
+            # If state_group is None it means it has yet to be assigned a
+            # state group, i.e. we need to make sure that calls with a state_group
+            # of None don't hit previous cached calls with a None state_group.
+            # To do this we set the state_group to a new object as object() != object()
+            state_group = object()
+
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
+        result = yield self._bulk_get_push_rules_for_room(
+            event.room_id, state_group, current_state_ids, event=event
+        )
+        return result
+
+    @cachedInlineCallbacks(num_args=2, cache_context=True)
+    def _bulk_get_push_rules_for_room(
+        self, room_id, state_group, current_state_ids, cache_context, event=None
+    ):
+        # We don't use `state_group`, its there so that we can cache based
+        # on it. However, its important that its never None, since two current_state's
+        # with a state_group of None are likely to be different.
+        # See bulk_get_push_rules_for_room for how we work around this.
+        assert state_group is not None
+
+        # We also will want to generate notifs for other people in the room so
+        # their unread countss are correct in the event stream, but to avoid
+        # generating them for bot / AS users etc, we only do so for people who've
+        # sent a read receipt into the room.
+
+        users_in_room = yield self._get_joined_users_from_context(
+            room_id,
+            state_group,
+            current_state_ids,
+            on_invalidate=cache_context.invalidate,
+            event=event,
+        )
+
+        # We ignore app service users for now. This is so that we don't fill
+        # up the `get_if_users_have_pushers` cache with AS entries that we
+        # know don't have pushers, nor even read receipts.
+        local_users_in_room = {
+            u
+            for u in users_in_room
+            if self.hs.is_mine_id(u)
+            and not self.get_if_app_services_interested_in_user(u)
+        }
+
+        # users in the room who have pushers need to get push rules run because
+        # that's how their pushers work
+        if_users_with_pushers = yield self.get_if_users_have_pushers(
+            local_users_in_room, on_invalidate=cache_context.invalidate
+        )
+        user_ids = {
+            uid for uid, have_pusher in if_users_with_pushers.items() if have_pusher
+        }
+
+        users_with_receipts = yield self.get_users_with_read_receipts_in_room(
+            room_id, on_invalidate=cache_context.invalidate
+        )
+
+        # any users with pushers must be ours: they have pushers
+        for uid in users_with_receipts:
+            if uid in local_users_in_room:
+                user_ids.add(uid)
+
+        rules_by_user = yield self.bulk_get_push_rules(
+            user_ids, on_invalidate=cache_context.invalidate
+        )
+
+        rules_by_user = {k: v for k, v in rules_by_user.items() if v is not None}
+
+        return rules_by_user
+
+    @cachedList(
+        cached_method_name="get_push_rules_enabled_for_user",
+        list_name="user_ids",
+        num_args=1,
+        inlineCallbacks=True,
+    )
+    def bulk_get_push_rules_enabled(self, user_ids):
+        if not user_ids:
+            return {}
+
+        results = {user_id: {} for user_id in user_ids}
+
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="push_rules_enable",
+            column="user_name",
+            iterable=user_ids,
+            retcols=("user_name", "rule_id", "enabled"),
+            desc="bulk_get_push_rules_enabled",
+        )
+        for row in rows:
+            enabled = bool(row["enabled"])
+            results.setdefault(row["user_name"], {})[row["rule_id"]] = enabled
+        return results
+
+    async def get_all_push_rule_updates(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for push_rules replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_push_rule_updates_txn(txn):
+            sql = """
+                SELECT stream_id, user_id
+                FROM push_rules_stream
+                WHERE ? < stream_id AND stream_id <= ?
+                ORDER BY stream_id ASC
+                LIMIT ?
+            """
+            txn.execute(sql, (last_id, current_id, limit))
+            updates = [(stream_id, (user_id,)) for stream_id, user_id in txn]
+
+            limited = False
+            upper_bound = current_id
+            if len(updates) == limit:
+                limited = True
+                upper_bound = updates[-1][0]
+
+            return updates, upper_bound, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_push_rule_updates", get_all_push_rule_updates_txn
+        )
+
+
+class PushRuleStore(PushRulesWorkerStore):
+    @defer.inlineCallbacks
+    def add_push_rule(
+        self,
+        user_id,
+        rule_id,
+        priority_class,
+        conditions,
+        actions,
+        before=None,
+        after=None,
+    ):
+        conditions_json = json.dumps(conditions)
+        actions_json = json.dumps(actions)
+        with self._push_rules_stream_id_gen.get_next() as ids:
+            stream_id, event_stream_ordering = ids
+            if before or after:
+                yield self.db_pool.runInteraction(
+                    "_add_push_rule_relative_txn",
+                    self._add_push_rule_relative_txn,
+                    stream_id,
+                    event_stream_ordering,
+                    user_id,
+                    rule_id,
+                    priority_class,
+                    conditions_json,
+                    actions_json,
+                    before,
+                    after,
+                )
+            else:
+                yield self.db_pool.runInteraction(
+                    "_add_push_rule_highest_priority_txn",
+                    self._add_push_rule_highest_priority_txn,
+                    stream_id,
+                    event_stream_ordering,
+                    user_id,
+                    rule_id,
+                    priority_class,
+                    conditions_json,
+                    actions_json,
+                )
+
+    def _add_push_rule_relative_txn(
+        self,
+        txn,
+        stream_id,
+        event_stream_ordering,
+        user_id,
+        rule_id,
+        priority_class,
+        conditions_json,
+        actions_json,
+        before,
+        after,
+    ):
+        # Lock the table since otherwise we'll have annoying races between the
+        # SELECT here and the UPSERT below.
+        self.database_engine.lock_table(txn, "push_rules")
+
+        relative_to_rule = before or after
+
+        res = self.db_pool.simple_select_one_txn(
+            txn,
+            table="push_rules",
+            keyvalues={"user_name": user_id, "rule_id": relative_to_rule},
+            retcols=["priority_class", "priority"],
+            allow_none=True,
+        )
+
+        if not res:
+            raise RuleNotFoundException(
+                "before/after rule not found: %s" % (relative_to_rule,)
+            )
+
+        base_priority_class = res["priority_class"]
+        base_rule_priority = res["priority"]
+
+        if base_priority_class != priority_class:
+            raise InconsistentRuleException(
+                "Given priority class does not match class of relative rule"
+            )
+
+        if before:
+            # Higher priority rules are executed first, So adding a rule before
+            # a rule means giving it a higher priority than that rule.
+            new_rule_priority = base_rule_priority + 1
+        else:
+            # We increment the priority of the existing rules to make space for
+            # the new rule. Therefore if we want this rule to appear after
+            # an existing rule we give it the priority of the existing rule,
+            # and then increment the priority of the existing rule.
+            new_rule_priority = base_rule_priority
+
+        sql = (
+            "UPDATE push_rules SET priority = priority + 1"
+            " WHERE user_name = ? AND priority_class = ? AND priority >= ?"
+        )
+
+        txn.execute(sql, (user_id, priority_class, new_rule_priority))
+
+        self._upsert_push_rule_txn(
+            txn,
+            stream_id,
+            event_stream_ordering,
+            user_id,
+            rule_id,
+            priority_class,
+            new_rule_priority,
+            conditions_json,
+            actions_json,
+        )
+
+    def _add_push_rule_highest_priority_txn(
+        self,
+        txn,
+        stream_id,
+        event_stream_ordering,
+        user_id,
+        rule_id,
+        priority_class,
+        conditions_json,
+        actions_json,
+    ):
+        # Lock the table since otherwise we'll have annoying races between the
+        # SELECT here and the UPSERT below.
+        self.database_engine.lock_table(txn, "push_rules")
+
+        # find the highest priority rule in that class
+        sql = (
+            "SELECT COUNT(*), MAX(priority) FROM push_rules"
+            " WHERE user_name = ? and priority_class = ?"
+        )
+        txn.execute(sql, (user_id, priority_class))
+        res = txn.fetchall()
+        (how_many, highest_prio) = res[0]
+
+        new_prio = 0
+        if how_many > 0:
+            new_prio = highest_prio + 1
+
+        self._upsert_push_rule_txn(
+            txn,
+            stream_id,
+            event_stream_ordering,
+            user_id,
+            rule_id,
+            priority_class,
+            new_prio,
+            conditions_json,
+            actions_json,
+        )
+
+    def _upsert_push_rule_txn(
+        self,
+        txn,
+        stream_id,
+        event_stream_ordering,
+        user_id,
+        rule_id,
+        priority_class,
+        priority,
+        conditions_json,
+        actions_json,
+        update_stream=True,
+    ):
+        """Specialised version of simple_upsert_txn that picks a push_rule_id
+        using the _push_rule_id_gen if it needs to insert the rule. It assumes
+        that the "push_rules" table is locked"""
+
+        sql = (
+            "UPDATE push_rules"
+            " SET priority_class = ?, priority = ?, conditions = ?, actions = ?"
+            " WHERE user_name = ? AND rule_id = ?"
+        )
+
+        txn.execute(
+            sql,
+            (priority_class, priority, conditions_json, actions_json, user_id, rule_id),
+        )
+
+        if txn.rowcount == 0:
+            # We didn't update a row with the given rule_id so insert one
+            push_rule_id = self._push_rule_id_gen.get_next()
+
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="push_rules",
+                values={
+                    "id": push_rule_id,
+                    "user_name": user_id,
+                    "rule_id": rule_id,
+                    "priority_class": priority_class,
+                    "priority": priority,
+                    "conditions": conditions_json,
+                    "actions": actions_json,
+                },
+            )
+
+        if update_stream:
+            self._insert_push_rules_update_txn(
+                txn,
+                stream_id,
+                event_stream_ordering,
+                user_id,
+                rule_id,
+                op="ADD",
+                data={
+                    "priority_class": priority_class,
+                    "priority": priority,
+                    "conditions": conditions_json,
+                    "actions": actions_json,
+                },
+            )
+
+    @defer.inlineCallbacks
+    def delete_push_rule(self, user_id, rule_id):
+        """
+        Delete a push rule. Args specify the row to be deleted and can be
+        any of the columns in the push_rule table, but below are the
+        standard ones
+
+        Args:
+            user_id (str): The matrix ID of the push rule owner
+            rule_id (str): The rule_id of the rule to be deleted
+        """
+
+        def delete_push_rule_txn(txn, stream_id, event_stream_ordering):
+            self.db_pool.simple_delete_one_txn(
+                txn, "push_rules", {"user_name": user_id, "rule_id": rule_id}
+            )
+
+            self._insert_push_rules_update_txn(
+                txn, stream_id, event_stream_ordering, user_id, rule_id, op="DELETE"
+            )
+
+        with self._push_rules_stream_id_gen.get_next() as ids:
+            stream_id, event_stream_ordering = ids
+            yield self.db_pool.runInteraction(
+                "delete_push_rule",
+                delete_push_rule_txn,
+                stream_id,
+                event_stream_ordering,
+            )
+
+    @defer.inlineCallbacks
+    def set_push_rule_enabled(self, user_id, rule_id, enabled):
+        with self._push_rules_stream_id_gen.get_next() as ids:
+            stream_id, event_stream_ordering = ids
+            yield self.db_pool.runInteraction(
+                "_set_push_rule_enabled_txn",
+                self._set_push_rule_enabled_txn,
+                stream_id,
+                event_stream_ordering,
+                user_id,
+                rule_id,
+                enabled,
+            )
+
+    def _set_push_rule_enabled_txn(
+        self, txn, stream_id, event_stream_ordering, user_id, rule_id, enabled
+    ):
+        new_id = self._push_rules_enable_id_gen.get_next()
+        self.db_pool.simple_upsert_txn(
+            txn,
+            "push_rules_enable",
+            {"user_name": user_id, "rule_id": rule_id},
+            {"enabled": 1 if enabled else 0},
+            {"id": new_id},
+        )
+
+        self._insert_push_rules_update_txn(
+            txn,
+            stream_id,
+            event_stream_ordering,
+            user_id,
+            rule_id,
+            op="ENABLE" if enabled else "DISABLE",
+        )
+
+    @defer.inlineCallbacks
+    def set_push_rule_actions(self, user_id, rule_id, actions, is_default_rule):
+        actions_json = json.dumps(actions)
+
+        def set_push_rule_actions_txn(txn, stream_id, event_stream_ordering):
+            if is_default_rule:
+                # Add a dummy rule to the rules table with the user specified
+                # actions.
+                priority_class = -1
+                priority = 1
+                self._upsert_push_rule_txn(
+                    txn,
+                    stream_id,
+                    event_stream_ordering,
+                    user_id,
+                    rule_id,
+                    priority_class,
+                    priority,
+                    "[]",
+                    actions_json,
+                    update_stream=False,
+                )
+            else:
+                self.db_pool.simple_update_one_txn(
+                    txn,
+                    "push_rules",
+                    {"user_name": user_id, "rule_id": rule_id},
+                    {"actions": actions_json},
+                )
+
+            self._insert_push_rules_update_txn(
+                txn,
+                stream_id,
+                event_stream_ordering,
+                user_id,
+                rule_id,
+                op="ACTIONS",
+                data={"actions": actions_json},
+            )
+
+        with self._push_rules_stream_id_gen.get_next() as ids:
+            stream_id, event_stream_ordering = ids
+            yield self.db_pool.runInteraction(
+                "set_push_rule_actions",
+                set_push_rule_actions_txn,
+                stream_id,
+                event_stream_ordering,
+            )
+
+    def _insert_push_rules_update_txn(
+        self, txn, stream_id, event_stream_ordering, user_id, rule_id, op, data=None
+    ):
+        values = {
+            "stream_id": stream_id,
+            "event_stream_ordering": event_stream_ordering,
+            "user_id": user_id,
+            "rule_id": rule_id,
+            "op": op,
+        }
+        if data is not None:
+            values.update(data)
+
+        self.db_pool.simple_insert_txn(txn, "push_rules_stream", values=values)
+
+        txn.call_after(self.get_push_rules_for_user.invalidate, (user_id,))
+        txn.call_after(self.get_push_rules_enabled_for_user.invalidate, (user_id,))
+        txn.call_after(
+            self.push_rules_stream_cache.entity_has_changed, user_id, stream_id
+        )
+
+    def get_push_rules_stream_token(self):
+        """Get the position of the push rules stream.
+        Returns a pair of a stream id for the push_rules stream and the
+        room stream ordering it corresponds to."""
+        return self._push_rules_stream_id_gen.get_current_token()
+
+    def get_max_push_rules_stream_id(self):
+        return self.get_push_rules_stream_token()[0]
diff --git a/synapse/storage/databases/main/pusher.py b/synapse/storage/databases/main/pusher.py
new file mode 100644
index 0000000000..b5200fbe79
--- /dev/null
+++ b/synapse/storage/databases/main/pusher.py
@@ -0,0 +1,356 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from typing import Iterable, Iterator, List, Tuple
+
+from canonicaljson import encode_canonical_json
+
+from twisted.internet import defer
+
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.util.caches.descriptors import cachedInlineCallbacks, cachedList
+
+logger = logging.getLogger(__name__)
+
+
+class PusherWorkerStore(SQLBaseStore):
+    def _decode_pushers_rows(self, rows: Iterable[dict]) -> Iterator[dict]:
+        """JSON-decode the data in the rows returned from the `pushers` table
+
+        Drops any rows whose data cannot be decoded
+        """
+        for r in rows:
+            dataJson = r["data"]
+            try:
+                r["data"] = db_to_json(dataJson)
+            except Exception as e:
+                logger.warning(
+                    "Invalid JSON in data for pusher %d: %s, %s",
+                    r["id"],
+                    dataJson,
+                    e.args[0],
+                )
+                continue
+
+            yield r
+
+    @defer.inlineCallbacks
+    def user_has_pusher(self, user_id):
+        ret = yield self.db_pool.simple_select_one_onecol(
+            "pushers", {"user_name": user_id}, "id", allow_none=True
+        )
+        return ret is not None
+
+    def get_pushers_by_app_id_and_pushkey(self, app_id, pushkey):
+        return self.get_pushers_by({"app_id": app_id, "pushkey": pushkey})
+
+    def get_pushers_by_user_id(self, user_id):
+        return self.get_pushers_by({"user_name": user_id})
+
+    @defer.inlineCallbacks
+    def get_pushers_by(self, keyvalues):
+        ret = yield self.db_pool.simple_select_list(
+            "pushers",
+            keyvalues,
+            [
+                "id",
+                "user_name",
+                "access_token",
+                "profile_tag",
+                "kind",
+                "app_id",
+                "app_display_name",
+                "device_display_name",
+                "pushkey",
+                "ts",
+                "lang",
+                "data",
+                "last_stream_ordering",
+                "last_success",
+                "failing_since",
+            ],
+            desc="get_pushers_by",
+        )
+        return self._decode_pushers_rows(ret)
+
+    @defer.inlineCallbacks
+    def get_all_pushers(self):
+        def get_pushers(txn):
+            txn.execute("SELECT * FROM pushers")
+            rows = self.db_pool.cursor_to_dict(txn)
+
+            return self._decode_pushers_rows(rows)
+
+        rows = yield self.db_pool.runInteraction("get_all_pushers", get_pushers)
+        return rows
+
+    async def get_all_updated_pushers_rows(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for pushers replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_updated_pushers_rows_txn(txn):
+            sql = """
+                SELECT id, user_name, app_id, pushkey
+                FROM pushers
+                WHERE ? < id AND id <= ?
+                ORDER BY id ASC LIMIT ?
+            """
+            txn.execute(sql, (last_id, current_id, limit))
+            updates = [
+                (stream_id, (user_name, app_id, pushkey, False))
+                for stream_id, user_name, app_id, pushkey in txn
+            ]
+
+            sql = """
+                SELECT stream_id, user_id, app_id, pushkey
+                FROM deleted_pushers
+                WHERE ? < stream_id AND stream_id <= ?
+                ORDER BY stream_id ASC LIMIT ?
+            """
+            txn.execute(sql, (last_id, current_id, limit))
+            updates.extend(
+                (stream_id, (user_name, app_id, pushkey, True))
+                for stream_id, user_name, app_id, pushkey in txn
+            )
+
+            updates.sort()  # Sort so that they're ordered by stream id
+
+            limited = False
+            upper_bound = current_id
+            if len(updates) >= limit:
+                limited = True
+                upper_bound = updates[-1][0]
+
+            return updates, upper_bound, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_updated_pushers_rows", get_all_updated_pushers_rows_txn
+        )
+
+    @cachedInlineCallbacks(num_args=1, max_entries=15000)
+    def get_if_user_has_pusher(self, user_id):
+        # This only exists for the cachedList decorator
+        raise NotImplementedError()
+
+    @cachedList(
+        cached_method_name="get_if_user_has_pusher",
+        list_name="user_ids",
+        num_args=1,
+        inlineCallbacks=True,
+    )
+    def get_if_users_have_pushers(self, user_ids):
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="pushers",
+            column="user_name",
+            iterable=user_ids,
+            retcols=["user_name"],
+            desc="get_if_users_have_pushers",
+        )
+
+        result = {user_id: False for user_id in user_ids}
+        result.update({r["user_name"]: True for r in rows})
+
+        return result
+
+    @defer.inlineCallbacks
+    def update_pusher_last_stream_ordering(
+        self, app_id, pushkey, user_id, last_stream_ordering
+    ):
+        yield self.db_pool.simple_update_one(
+            "pushers",
+            {"app_id": app_id, "pushkey": pushkey, "user_name": user_id},
+            {"last_stream_ordering": last_stream_ordering},
+            desc="update_pusher_last_stream_ordering",
+        )
+
+    @defer.inlineCallbacks
+    def update_pusher_last_stream_ordering_and_success(
+        self, app_id, pushkey, user_id, last_stream_ordering, last_success
+    ):
+        """Update the last stream ordering position we've processed up to for
+        the given pusher.
+
+        Args:
+            app_id (str)
+            pushkey (str)
+            last_stream_ordering (int)
+            last_success (int)
+
+        Returns:
+            Deferred[bool]: True if the pusher still exists; False if it has been deleted.
+        """
+        updated = yield self.db_pool.simple_update(
+            table="pushers",
+            keyvalues={"app_id": app_id, "pushkey": pushkey, "user_name": user_id},
+            updatevalues={
+                "last_stream_ordering": last_stream_ordering,
+                "last_success": last_success,
+            },
+            desc="update_pusher_last_stream_ordering_and_success",
+        )
+
+        return bool(updated)
+
+    @defer.inlineCallbacks
+    def update_pusher_failing_since(self, app_id, pushkey, user_id, failing_since):
+        yield self.db_pool.simple_update(
+            table="pushers",
+            keyvalues={"app_id": app_id, "pushkey": pushkey, "user_name": user_id},
+            updatevalues={"failing_since": failing_since},
+            desc="update_pusher_failing_since",
+        )
+
+    @defer.inlineCallbacks
+    def get_throttle_params_by_room(self, pusher_id):
+        res = yield self.db_pool.simple_select_list(
+            "pusher_throttle",
+            {"pusher": pusher_id},
+            ["room_id", "last_sent_ts", "throttle_ms"],
+            desc="get_throttle_params_by_room",
+        )
+
+        params_by_room = {}
+        for row in res:
+            params_by_room[row["room_id"]] = {
+                "last_sent_ts": row["last_sent_ts"],
+                "throttle_ms": row["throttle_ms"],
+            }
+
+        return params_by_room
+
+    @defer.inlineCallbacks
+    def set_throttle_params(self, pusher_id, room_id, params):
+        # no need to lock because `pusher_throttle` has a primary key on
+        # (pusher, room_id) so simple_upsert will retry
+        yield self.db_pool.simple_upsert(
+            "pusher_throttle",
+            {"pusher": pusher_id, "room_id": room_id},
+            params,
+            desc="set_throttle_params",
+            lock=False,
+        )
+
+
+class PusherStore(PusherWorkerStore):
+    def get_pushers_stream_token(self):
+        return self._pushers_id_gen.get_current_token()
+
+    @defer.inlineCallbacks
+    def add_pusher(
+        self,
+        user_id,
+        access_token,
+        kind,
+        app_id,
+        app_display_name,
+        device_display_name,
+        pushkey,
+        pushkey_ts,
+        lang,
+        data,
+        last_stream_ordering,
+        profile_tag="",
+    ):
+        with self._pushers_id_gen.get_next() as stream_id:
+            # no need to lock because `pushers` has a unique key on
+            # (app_id, pushkey, user_name) so simple_upsert will retry
+            yield self.db_pool.simple_upsert(
+                table="pushers",
+                keyvalues={"app_id": app_id, "pushkey": pushkey, "user_name": user_id},
+                values={
+                    "access_token": access_token,
+                    "kind": kind,
+                    "app_display_name": app_display_name,
+                    "device_display_name": device_display_name,
+                    "ts": pushkey_ts,
+                    "lang": lang,
+                    "data": bytearray(encode_canonical_json(data)),
+                    "last_stream_ordering": last_stream_ordering,
+                    "profile_tag": profile_tag,
+                    "id": stream_id,
+                },
+                desc="add_pusher",
+                lock=False,
+            )
+
+            user_has_pusher = self.get_if_user_has_pusher.cache.get(
+                (user_id,), None, update_metrics=False
+            )
+
+            if user_has_pusher is not True:
+                # invalidate, since we the user might not have had a pusher before
+                yield self.db_pool.runInteraction(
+                    "add_pusher",
+                    self._invalidate_cache_and_stream,
+                    self.get_if_user_has_pusher,
+                    (user_id,),
+                )
+
+    @defer.inlineCallbacks
+    def delete_pusher_by_app_id_pushkey_user_id(self, app_id, pushkey, user_id):
+        def delete_pusher_txn(txn, stream_id):
+            self._invalidate_cache_and_stream(
+                txn, self.get_if_user_has_pusher, (user_id,)
+            )
+
+            self.db_pool.simple_delete_one_txn(
+                txn,
+                "pushers",
+                {"app_id": app_id, "pushkey": pushkey, "user_name": user_id},
+            )
+
+            # it's possible for us to end up with duplicate rows for
+            # (app_id, pushkey, user_id) at different stream_ids, but that
+            # doesn't really matter.
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="deleted_pushers",
+                values={
+                    "stream_id": stream_id,
+                    "app_id": app_id,
+                    "pushkey": pushkey,
+                    "user_id": user_id,
+                },
+            )
+
+        with self._pushers_id_gen.get_next() as stream_id:
+            yield self.db_pool.runInteraction(
+                "delete_pusher", delete_pusher_txn, stream_id
+            )
diff --git a/synapse/storage/databases/main/receipts.py b/synapse/storage/databases/main/receipts.py
new file mode 100644
index 0000000000..6255977c92
--- /dev/null
+++ b/synapse/storage/databases/main/receipts.py
@@ -0,0 +1,591 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import abc
+import logging
+from typing import List, Tuple
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
+from synapse.storage.database import DatabasePool
+from synapse.storage.util.id_generators import StreamIdGenerator
+from synapse.util.async_helpers import ObservableDeferred
+from synapse.util.caches.descriptors import cached, cachedInlineCallbacks, cachedList
+from synapse.util.caches.stream_change_cache import StreamChangeCache
+
+logger = logging.getLogger(__name__)
+
+
+class ReceiptsWorkerStore(SQLBaseStore):
+    """This is an abstract base class where subclasses must implement
+    `get_max_receipt_stream_id` which can be called in the initializer.
+    """
+
+    # This ABCMeta metaclass ensures that we cannot be instantiated without
+    # the abstract methods being implemented.
+    __metaclass__ = abc.ABCMeta
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(ReceiptsWorkerStore, self).__init__(database, db_conn, hs)
+
+        self._receipts_stream_cache = StreamChangeCache(
+            "ReceiptsRoomChangeCache", self.get_max_receipt_stream_id()
+        )
+
+    @abc.abstractmethod
+    def get_max_receipt_stream_id(self):
+        """Get the current max stream ID for receipts stream
+
+        Returns:
+            int
+        """
+        raise NotImplementedError()
+
+    @cachedInlineCallbacks()
+    def get_users_with_read_receipts_in_room(self, room_id):
+        receipts = yield self.get_receipts_for_room(room_id, "m.read")
+        return {r["user_id"] for r in receipts}
+
+    @cached(num_args=2)
+    def get_receipts_for_room(self, room_id, receipt_type):
+        return self.db_pool.simple_select_list(
+            table="receipts_linearized",
+            keyvalues={"room_id": room_id, "receipt_type": receipt_type},
+            retcols=("user_id", "event_id"),
+            desc="get_receipts_for_room",
+        )
+
+    @cached(num_args=3)
+    def get_last_receipt_event_id_for_user(self, user_id, room_id, receipt_type):
+        return self.db_pool.simple_select_one_onecol(
+            table="receipts_linearized",
+            keyvalues={
+                "room_id": room_id,
+                "receipt_type": receipt_type,
+                "user_id": user_id,
+            },
+            retcol="event_id",
+            desc="get_own_receipt_for_user",
+            allow_none=True,
+        )
+
+    @cachedInlineCallbacks(num_args=2)
+    def get_receipts_for_user(self, user_id, receipt_type):
+        rows = yield self.db_pool.simple_select_list(
+            table="receipts_linearized",
+            keyvalues={"user_id": user_id, "receipt_type": receipt_type},
+            retcols=("room_id", "event_id"),
+            desc="get_receipts_for_user",
+        )
+
+        return {row["room_id"]: row["event_id"] for row in rows}
+
+    @defer.inlineCallbacks
+    def get_receipts_for_user_with_orderings(self, user_id, receipt_type):
+        def f(txn):
+            sql = (
+                "SELECT rl.room_id, rl.event_id,"
+                " e.topological_ordering, e.stream_ordering"
+                " FROM receipts_linearized AS rl"
+                " INNER JOIN events AS e USING (room_id, event_id)"
+                " WHERE rl.room_id = e.room_id"
+                " AND rl.event_id = e.event_id"
+                " AND user_id = ?"
+            )
+            txn.execute(sql, (user_id,))
+            return txn.fetchall()
+
+        rows = yield self.db_pool.runInteraction(
+            "get_receipts_for_user_with_orderings", f
+        )
+        return {
+            row[0]: {
+                "event_id": row[1],
+                "topological_ordering": row[2],
+                "stream_ordering": row[3],
+            }
+            for row in rows
+        }
+
+    @defer.inlineCallbacks
+    def get_linearized_receipts_for_rooms(self, room_ids, to_key, from_key=None):
+        """Get receipts for multiple rooms for sending to clients.
+
+        Args:
+            room_ids (list): List of room_ids.
+            to_key (int): Max stream id to fetch receipts upto.
+            from_key (int): Min stream id to fetch receipts from. None fetches
+                from the start.
+
+        Returns:
+            list: A list of receipts.
+        """
+        room_ids = set(room_ids)
+
+        if from_key is not None:
+            # Only ask the database about rooms where there have been new
+            # receipts added since `from_key`
+            room_ids = yield self._receipts_stream_cache.get_entities_changed(
+                room_ids, from_key
+            )
+
+        results = yield self._get_linearized_receipts_for_rooms(
+            room_ids, to_key, from_key=from_key
+        )
+
+        return [ev for res in results.values() for ev in res]
+
+    def get_linearized_receipts_for_room(self, room_id, to_key, from_key=None):
+        """Get receipts for a single room for sending to clients.
+
+        Args:
+            room_ids (str): The room id.
+            to_key (int): Max stream id to fetch receipts upto.
+            from_key (int): Min stream id to fetch receipts from. None fetches
+                from the start.
+
+        Returns:
+            Deferred[list]: A list of receipts.
+        """
+        if from_key is not None:
+            # Check the cache first to see if any new receipts have been added
+            # since`from_key`. If not we can no-op.
+            if not self._receipts_stream_cache.has_entity_changed(room_id, from_key):
+                defer.succeed([])
+
+        return self._get_linearized_receipts_for_room(room_id, to_key, from_key)
+
+    @cachedInlineCallbacks(num_args=3, tree=True)
+    def _get_linearized_receipts_for_room(self, room_id, to_key, from_key=None):
+        """See get_linearized_receipts_for_room
+        """
+
+        def f(txn):
+            if from_key:
+                sql = (
+                    "SELECT * FROM receipts_linearized WHERE"
+                    " room_id = ? AND stream_id > ? AND stream_id <= ?"
+                )
+
+                txn.execute(sql, (room_id, from_key, to_key))
+            else:
+                sql = (
+                    "SELECT * FROM receipts_linearized WHERE"
+                    " room_id = ? AND stream_id <= ?"
+                )
+
+                txn.execute(sql, (room_id, to_key))
+
+            rows = self.db_pool.cursor_to_dict(txn)
+
+            return rows
+
+        rows = yield self.db_pool.runInteraction("get_linearized_receipts_for_room", f)
+
+        if not rows:
+            return []
+
+        content = {}
+        for row in rows:
+            content.setdefault(row["event_id"], {}).setdefault(row["receipt_type"], {})[
+                row["user_id"]
+            ] = db_to_json(row["data"])
+
+        return [{"type": "m.receipt", "room_id": room_id, "content": content}]
+
+    @cachedList(
+        cached_method_name="_get_linearized_receipts_for_room",
+        list_name="room_ids",
+        num_args=3,
+        inlineCallbacks=True,
+    )
+    def _get_linearized_receipts_for_rooms(self, room_ids, to_key, from_key=None):
+        if not room_ids:
+            return {}
+
+        def f(txn):
+            if from_key:
+                sql = """
+                    SELECT * FROM receipts_linearized WHERE
+                    stream_id > ? AND stream_id <= ? AND
+                """
+                clause, args = make_in_list_sql_clause(
+                    self.database_engine, "room_id", room_ids
+                )
+
+                txn.execute(sql + clause, [from_key, to_key] + list(args))
+            else:
+                sql = """
+                    SELECT * FROM receipts_linearized WHERE
+                    stream_id <= ? AND
+                """
+
+                clause, args = make_in_list_sql_clause(
+                    self.database_engine, "room_id", room_ids
+                )
+
+                txn.execute(sql + clause, [to_key] + list(args))
+
+            return self.db_pool.cursor_to_dict(txn)
+
+        txn_results = yield self.db_pool.runInteraction(
+            "_get_linearized_receipts_for_rooms", f
+        )
+
+        results = {}
+        for row in txn_results:
+            # We want a single event per room, since we want to batch the
+            # receipts by room, event and type.
+            room_event = results.setdefault(
+                row["room_id"],
+                {"type": "m.receipt", "room_id": row["room_id"], "content": {}},
+            )
+
+            # The content is of the form:
+            # {"$foo:bar": { "read": { "@user:host": <receipt> }, .. }, .. }
+            event_entry = room_event["content"].setdefault(row["event_id"], {})
+            receipt_type = event_entry.setdefault(row["receipt_type"], {})
+
+            receipt_type[row["user_id"]] = db_to_json(row["data"])
+
+        results = {
+            room_id: [results[room_id]] if room_id in results else []
+            for room_id in room_ids
+        }
+        return results
+
+    def get_users_sent_receipts_between(self, last_id: int, current_id: int):
+        """Get all users who sent receipts between `last_id` exclusive and
+        `current_id` inclusive.
+
+        Returns:
+            Deferred[List[str]]
+        """
+
+        if last_id == current_id:
+            return defer.succeed([])
+
+        def _get_users_sent_receipts_between_txn(txn):
+            sql = """
+                SELECT DISTINCT user_id FROM receipts_linearized
+                WHERE ? < stream_id AND stream_id <= ?
+            """
+            txn.execute(sql, (last_id, current_id))
+
+            return [r[0] for r in txn]
+
+        return self.db_pool.runInteraction(
+            "get_users_sent_receipts_between", _get_users_sent_receipts_between_txn
+        )
+
+    async def get_all_updated_receipts(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, list]], int, bool]:
+        """Get updates for receipts replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_updated_receipts_txn(txn):
+            sql = """
+                SELECT stream_id, room_id, receipt_type, user_id, event_id, data
+                FROM receipts_linearized
+                WHERE ? < stream_id AND stream_id <= ?
+                ORDER BY stream_id ASC
+                LIMIT ?
+            """
+            txn.execute(sql, (last_id, current_id, limit))
+
+            updates = [(r[0], r[1:5] + (db_to_json(r[5]),)) for r in txn]
+
+            limited = False
+            upper_bound = current_id
+
+            if len(updates) == limit:
+                limited = True
+                upper_bound = updates[-1][0]
+
+            return updates, upper_bound, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_updated_receipts", get_all_updated_receipts_txn
+        )
+
+    def _invalidate_get_users_with_receipts_in_room(
+        self, room_id, receipt_type, user_id
+    ):
+        if receipt_type != "m.read":
+            return
+
+        # Returns either an ObservableDeferred or the raw result
+        res = self.get_users_with_read_receipts_in_room.cache.get(
+            room_id, None, update_metrics=False
+        )
+
+        # first handle the ObservableDeferred case
+        if isinstance(res, ObservableDeferred):
+            if res.has_called():
+                res = res.get_result()
+            else:
+                res = None
+
+        if res and user_id in res:
+            # We'd only be adding to the set, so no point invalidating if the
+            # user is already there
+            return
+
+        self.get_users_with_read_receipts_in_room.invalidate((room_id,))
+
+
+class ReceiptsStore(ReceiptsWorkerStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        # We instantiate this first as the ReceiptsWorkerStore constructor
+        # needs to be able to call get_max_receipt_stream_id
+        self._receipts_id_gen = StreamIdGenerator(
+            db_conn, "receipts_linearized", "stream_id"
+        )
+
+        super(ReceiptsStore, self).__init__(database, db_conn, hs)
+
+    def get_max_receipt_stream_id(self):
+        return self._receipts_id_gen.get_current_token()
+
+    def insert_linearized_receipt_txn(
+        self, txn, room_id, receipt_type, user_id, event_id, data, stream_id
+    ):
+        """Inserts a read-receipt into the database if it's newer than the current RR
+
+        Returns: int|None
+            None if the RR is older than the current RR
+            otherwise, the rx timestamp of the event that the RR corresponds to
+                (or 0 if the event is unknown)
+        """
+        res = self.db_pool.simple_select_one_txn(
+            txn,
+            table="events",
+            retcols=["stream_ordering", "received_ts"],
+            keyvalues={"event_id": event_id},
+            allow_none=True,
+        )
+
+        stream_ordering = int(res["stream_ordering"]) if res else None
+        rx_ts = res["received_ts"] if res else 0
+
+        # We don't want to clobber receipts for more recent events, so we
+        # have to compare orderings of existing receipts
+        if stream_ordering is not None:
+            sql = (
+                "SELECT stream_ordering, event_id FROM events"
+                " INNER JOIN receipts_linearized as r USING (event_id, room_id)"
+                " WHERE r.room_id = ? AND r.receipt_type = ? AND r.user_id = ?"
+            )
+            txn.execute(sql, (room_id, receipt_type, user_id))
+
+            for so, eid in txn:
+                if int(so) >= stream_ordering:
+                    logger.debug(
+                        "Ignoring new receipt for %s in favour of existing "
+                        "one for later event %s",
+                        event_id,
+                        eid,
+                    )
+                    return None
+
+        txn.call_after(self.get_receipts_for_room.invalidate, (room_id, receipt_type))
+        txn.call_after(
+            self._invalidate_get_users_with_receipts_in_room,
+            room_id,
+            receipt_type,
+            user_id,
+        )
+        txn.call_after(self.get_receipts_for_user.invalidate, (user_id, receipt_type))
+        # FIXME: This shouldn't invalidate the whole cache
+        txn.call_after(
+            self._get_linearized_receipts_for_room.invalidate_many, (room_id,)
+        )
+
+        txn.call_after(
+            self._receipts_stream_cache.entity_has_changed, room_id, stream_id
+        )
+
+        txn.call_after(
+            self.get_last_receipt_event_id_for_user.invalidate,
+            (user_id, room_id, receipt_type),
+        )
+
+        self.db_pool.simple_upsert_txn(
+            txn,
+            table="receipts_linearized",
+            keyvalues={
+                "room_id": room_id,
+                "receipt_type": receipt_type,
+                "user_id": user_id,
+            },
+            values={
+                "stream_id": stream_id,
+                "event_id": event_id,
+                "data": json.dumps(data),
+            },
+            # receipts_linearized has a unique constraint on
+            # (user_id, room_id, receipt_type), so no need to lock
+            lock=False,
+        )
+
+        if receipt_type == "m.read" and stream_ordering is not None:
+            self._remove_old_push_actions_before_txn(
+                txn, room_id=room_id, user_id=user_id, stream_ordering=stream_ordering
+            )
+
+        return rx_ts
+
+    @defer.inlineCallbacks
+    def insert_receipt(self, room_id, receipt_type, user_id, event_ids, data):
+        """Insert a receipt, either from local client or remote server.
+
+        Automatically does conversion between linearized and graph
+        representations.
+        """
+        if not event_ids:
+            return
+
+        if len(event_ids) == 1:
+            linearized_event_id = event_ids[0]
+        else:
+            # we need to points in graph -> linearized form.
+            # TODO: Make this better.
+            def graph_to_linear(txn):
+                clause, args = make_in_list_sql_clause(
+                    self.database_engine, "event_id", event_ids
+                )
+
+                sql = """
+                    SELECT event_id WHERE room_id = ? AND stream_ordering IN (
+                        SELECT max(stream_ordering) WHERE %s
+                    )
+                """ % (
+                    clause,
+                )
+
+                txn.execute(sql, [room_id] + list(args))
+                rows = txn.fetchall()
+                if rows:
+                    return rows[0][0]
+                else:
+                    raise RuntimeError("Unrecognized event_ids: %r" % (event_ids,))
+
+            linearized_event_id = yield self.db_pool.runInteraction(
+                "insert_receipt_conv", graph_to_linear
+            )
+
+        stream_id_manager = self._receipts_id_gen.get_next()
+        with stream_id_manager as stream_id:
+            event_ts = yield self.db_pool.runInteraction(
+                "insert_linearized_receipt",
+                self.insert_linearized_receipt_txn,
+                room_id,
+                receipt_type,
+                user_id,
+                linearized_event_id,
+                data,
+                stream_id=stream_id,
+            )
+
+        if event_ts is None:
+            return None
+
+        now = self._clock.time_msec()
+        logger.debug(
+            "RR for event %s in %s (%i ms old)",
+            linearized_event_id,
+            room_id,
+            now - event_ts,
+        )
+
+        yield self.insert_graph_receipt(room_id, receipt_type, user_id, event_ids, data)
+
+        max_persisted_id = self._receipts_id_gen.get_current_token()
+
+        return stream_id, max_persisted_id
+
+    def insert_graph_receipt(self, room_id, receipt_type, user_id, event_ids, data):
+        return self.db_pool.runInteraction(
+            "insert_graph_receipt",
+            self.insert_graph_receipt_txn,
+            room_id,
+            receipt_type,
+            user_id,
+            event_ids,
+            data,
+        )
+
+    def insert_graph_receipt_txn(
+        self, txn, room_id, receipt_type, user_id, event_ids, data
+    ):
+        txn.call_after(self.get_receipts_for_room.invalidate, (room_id, receipt_type))
+        txn.call_after(
+            self._invalidate_get_users_with_receipts_in_room,
+            room_id,
+            receipt_type,
+            user_id,
+        )
+        txn.call_after(self.get_receipts_for_user.invalidate, (user_id, receipt_type))
+        # FIXME: This shouldn't invalidate the whole cache
+        txn.call_after(
+            self._get_linearized_receipts_for_room.invalidate_many, (room_id,)
+        )
+
+        self.db_pool.simple_delete_txn(
+            txn,
+            table="receipts_graph",
+            keyvalues={
+                "room_id": room_id,
+                "receipt_type": receipt_type,
+                "user_id": user_id,
+            },
+        )
+        self.db_pool.simple_insert_txn(
+            txn,
+            table="receipts_graph",
+            values={
+                "room_id": room_id,
+                "receipt_type": receipt_type,
+                "user_id": user_id,
+                "event_ids": json.dumps(event_ids),
+                "data": json.dumps(data),
+            },
+        )
diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
new file mode 100644
index 0000000000..f618629e09
--- /dev/null
+++ b/synapse/storage/databases/main/registration.py
@@ -0,0 +1,1588 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2017-2018 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import re
+from typing import Optional
+
+from twisted.internet import defer
+from twisted.internet.defer import Deferred
+
+from synapse.api.constants import UserTypes
+from synapse.api.errors import Codes, StoreError, SynapseError, ThreepidValidationError
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool
+from synapse.storage.types import Cursor
+from synapse.storage.util.sequence import build_sequence_generator
+from synapse.types import UserID
+from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
+
+THIRTY_MINUTES_IN_MS = 30 * 60 * 1000
+
+logger = logging.getLogger(__name__)
+
+
+class RegistrationWorkerStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RegistrationWorkerStore, self).__init__(database, db_conn, hs)
+
+        self.config = hs.config
+        self.clock = hs.get_clock()
+
+        self._user_id_seq = build_sequence_generator(
+            database.engine, find_max_generated_user_id_localpart, "user_id_seq",
+        )
+
+    @cached()
+    def get_user_by_id(self, user_id):
+        return self.db_pool.simple_select_one(
+            table="users",
+            keyvalues={"name": user_id},
+            retcols=[
+                "name",
+                "password_hash",
+                "is_guest",
+                "admin",
+                "consent_version",
+                "consent_server_notice_sent",
+                "appservice_id",
+                "creation_ts",
+                "user_type",
+                "deactivated",
+            ],
+            allow_none=True,
+            desc="get_user_by_id",
+        )
+
+    @defer.inlineCallbacks
+    def is_trial_user(self, user_id):
+        """Checks if user is in the "trial" period, i.e. within the first
+        N days of registration defined by `mau_trial_days` config
+
+        Args:
+            user_id (str)
+
+        Returns:
+            Deferred[bool]
+        """
+
+        info = yield self.get_user_by_id(user_id)
+        if not info:
+            return False
+
+        now = self.clock.time_msec()
+        trial_duration_ms = self.config.mau_trial_days * 24 * 60 * 60 * 1000
+        is_trial = (now - info["creation_ts"] * 1000) < trial_duration_ms
+        return is_trial
+
+    @cached()
+    def get_user_by_access_token(self, token):
+        """Get a user from the given access token.
+
+        Args:
+            token (str): The access token of a user.
+        Returns:
+            defer.Deferred: None, if the token did not match, otherwise dict
+                including the keys `name`, `is_guest`, `device_id`, `token_id`,
+                `valid_until_ms`.
+        """
+        return self.db_pool.runInteraction(
+            "get_user_by_access_token", self._query_for_auth, token
+        )
+
+    @cachedInlineCallbacks()
+    def get_expiration_ts_for_user(self, user_id):
+        """Get the expiration timestamp for the account bearing a given user ID.
+
+        Args:
+            user_id (str): The ID of the user.
+        Returns:
+            defer.Deferred: None, if the account has no expiration timestamp,
+                otherwise int representation of the timestamp (as a number of
+                milliseconds since epoch).
+        """
+        res = yield self.db_pool.simple_select_one_onecol(
+            table="account_validity",
+            keyvalues={"user_id": user_id},
+            retcol="expiration_ts_ms",
+            allow_none=True,
+            desc="get_expiration_ts_for_user",
+        )
+        return res
+
+    @defer.inlineCallbacks
+    def set_account_validity_for_user(
+        self, user_id, expiration_ts, email_sent, renewal_token=None
+    ):
+        """Updates the account validity properties of the given account, with the
+        given values.
+
+        Args:
+            user_id (str): ID of the account to update properties for.
+            expiration_ts (int): New expiration date, as a timestamp in milliseconds
+                since epoch.
+            email_sent (bool): True means a renewal email has been sent for this
+                account and there's no need to send another one for the current validity
+                period.
+            renewal_token (str): Renewal token the user can use to extend the validity
+                of their account. Defaults to no token.
+        """
+
+        def set_account_validity_for_user_txn(txn):
+            self.db_pool.simple_update_txn(
+                txn=txn,
+                table="account_validity",
+                keyvalues={"user_id": user_id},
+                updatevalues={
+                    "expiration_ts_ms": expiration_ts,
+                    "email_sent": email_sent,
+                    "renewal_token": renewal_token,
+                },
+            )
+            self._invalidate_cache_and_stream(
+                txn, self.get_expiration_ts_for_user, (user_id,)
+            )
+
+        yield self.db_pool.runInteraction(
+            "set_account_validity_for_user", set_account_validity_for_user_txn
+        )
+
+    @defer.inlineCallbacks
+    def set_renewal_token_for_user(self, user_id, renewal_token):
+        """Defines a renewal token for a given user.
+
+        Args:
+            user_id (str): ID of the user to set the renewal token for.
+            renewal_token (str): Random unique string that will be used to renew the
+                user's account.
+
+        Raises:
+            StoreError: The provided token is already set for another user.
+        """
+        yield self.db_pool.simple_update_one(
+            table="account_validity",
+            keyvalues={"user_id": user_id},
+            updatevalues={"renewal_token": renewal_token},
+            desc="set_renewal_token_for_user",
+        )
+
+    @defer.inlineCallbacks
+    def get_user_from_renewal_token(self, renewal_token):
+        """Get a user ID from a renewal token.
+
+        Args:
+            renewal_token (str): The renewal token to perform the lookup with.
+
+        Returns:
+            defer.Deferred[str]: The ID of the user to which the token belongs.
+        """
+        res = yield self.db_pool.simple_select_one_onecol(
+            table="account_validity",
+            keyvalues={"renewal_token": renewal_token},
+            retcol="user_id",
+            desc="get_user_from_renewal_token",
+        )
+
+        return res
+
+    @defer.inlineCallbacks
+    def get_renewal_token_for_user(self, user_id):
+        """Get the renewal token associated with a given user ID.
+
+        Args:
+            user_id (str): The user ID to lookup a token for.
+
+        Returns:
+            defer.Deferred[str]: The renewal token associated with this user ID.
+        """
+        res = yield self.db_pool.simple_select_one_onecol(
+            table="account_validity",
+            keyvalues={"user_id": user_id},
+            retcol="renewal_token",
+            desc="get_renewal_token_for_user",
+        )
+
+        return res
+
+    @defer.inlineCallbacks
+    def get_users_expiring_soon(self):
+        """Selects users whose account will expire in the [now, now + renew_at] time
+        window (see configuration for account_validity for information on what renew_at
+        refers to).
+
+        Returns:
+            Deferred: Resolves to a list[dict[user_id (str), expiration_ts_ms (int)]]
+        """
+
+        def select_users_txn(txn, now_ms, renew_at):
+            sql = (
+                "SELECT user_id, expiration_ts_ms FROM account_validity"
+                " WHERE email_sent = ? AND (expiration_ts_ms - ?) <= ?"
+            )
+            values = [False, now_ms, renew_at]
+            txn.execute(sql, values)
+            return self.db_pool.cursor_to_dict(txn)
+
+        res = yield self.db_pool.runInteraction(
+            "get_users_expiring_soon",
+            select_users_txn,
+            self.clock.time_msec(),
+            self.config.account_validity.renew_at,
+        )
+
+        return res
+
+    @defer.inlineCallbacks
+    def set_renewal_mail_status(self, user_id, email_sent):
+        """Sets or unsets the flag that indicates whether a renewal email has been sent
+        to the user (and the user hasn't renewed their account yet).
+
+        Args:
+            user_id (str): ID of the user to set/unset the flag for.
+            email_sent (bool): Flag which indicates whether a renewal email has been sent
+                to this user.
+        """
+        yield self.db_pool.simple_update_one(
+            table="account_validity",
+            keyvalues={"user_id": user_id},
+            updatevalues={"email_sent": email_sent},
+            desc="set_renewal_mail_status",
+        )
+
+    @defer.inlineCallbacks
+    def delete_account_validity_for_user(self, user_id):
+        """Deletes the entry for the given user in the account validity table, removing
+        their expiration date and renewal token.
+
+        Args:
+            user_id (str): ID of the user to remove from the account validity table.
+        """
+        yield self.db_pool.simple_delete_one(
+            table="account_validity",
+            keyvalues={"user_id": user_id},
+            desc="delete_account_validity_for_user",
+        )
+
+    async def is_server_admin(self, user):
+        """Determines if a user is an admin of this homeserver.
+
+        Args:
+            user (UserID): user ID of the user to test
+
+        Returns (bool):
+            true iff the user is a server admin, false otherwise.
+        """
+        res = await self.db_pool.simple_select_one_onecol(
+            table="users",
+            keyvalues={"name": user.to_string()},
+            retcol="admin",
+            allow_none=True,
+            desc="is_server_admin",
+        )
+
+        return bool(res) if res else False
+
+    def set_server_admin(self, user, admin):
+        """Sets whether a user is an admin of this homeserver.
+
+        Args:
+            user (UserID): user ID of the user to test
+            admin (bool): true iff the user is to be a server admin,
+                false otherwise.
+        """
+
+        def set_server_admin_txn(txn):
+            self.db_pool.simple_update_one_txn(
+                txn, "users", {"name": user.to_string()}, {"admin": 1 if admin else 0}
+            )
+            self._invalidate_cache_and_stream(
+                txn, self.get_user_by_id, (user.to_string(),)
+            )
+
+        return self.db_pool.runInteraction("set_server_admin", set_server_admin_txn)
+
+    def _query_for_auth(self, txn, token):
+        sql = (
+            "SELECT users.name, users.is_guest, access_tokens.id as token_id,"
+            " access_tokens.device_id, access_tokens.valid_until_ms"
+            " FROM users"
+            " INNER JOIN access_tokens on users.name = access_tokens.user_id"
+            " WHERE token = ?"
+        )
+
+        txn.execute(sql, (token,))
+        rows = self.db_pool.cursor_to_dict(txn)
+        if rows:
+            return rows[0]
+
+        return None
+
+    @cachedInlineCallbacks()
+    def is_real_user(self, user_id):
+        """Determines if the user is a real user, ie does not have a 'user_type'.
+
+        Args:
+            user_id (str): user id to test
+
+        Returns:
+            Deferred[bool]: True if user 'user_type' is null or empty string
+        """
+        res = yield self.db_pool.runInteraction(
+            "is_real_user", self.is_real_user_txn, user_id
+        )
+        return res
+
+    @cached()
+    def is_support_user(self, user_id):
+        """Determines if the user is of type UserTypes.SUPPORT
+
+        Args:
+            user_id (str): user id to test
+
+        Returns:
+            Deferred[bool]: True if user is of type UserTypes.SUPPORT
+        """
+        return self.db_pool.runInteraction(
+            "is_support_user", self.is_support_user_txn, user_id
+        )
+
+    def is_real_user_txn(self, txn, user_id):
+        res = self.db_pool.simple_select_one_onecol_txn(
+            txn=txn,
+            table="users",
+            keyvalues={"name": user_id},
+            retcol="user_type",
+            allow_none=True,
+        )
+        return res is None
+
+    def is_support_user_txn(self, txn, user_id):
+        res = self.db_pool.simple_select_one_onecol_txn(
+            txn=txn,
+            table="users",
+            keyvalues={"name": user_id},
+            retcol="user_type",
+            allow_none=True,
+        )
+        return True if res == UserTypes.SUPPORT else False
+
+    def get_users_by_id_case_insensitive(self, user_id):
+        """Gets users that match user_id case insensitively.
+        Returns a mapping of user_id -> password_hash.
+        """
+
+        def f(txn):
+            sql = "SELECT name, password_hash FROM users WHERE lower(name) = lower(?)"
+            txn.execute(sql, (user_id,))
+            return dict(txn)
+
+        return self.db_pool.runInteraction("get_users_by_id_case_insensitive", f)
+
+    async def get_user_by_external_id(
+        self, auth_provider: str, external_id: str
+    ) -> str:
+        """Look up a user by their external auth id
+
+        Args:
+            auth_provider: identifier for the remote auth provider
+            external_id: id on that system
+
+        Returns:
+            str|None: the mxid of the user, or None if they are not known
+        """
+        return await self.db_pool.simple_select_one_onecol(
+            table="user_external_ids",
+            keyvalues={"auth_provider": auth_provider, "external_id": external_id},
+            retcol="user_id",
+            allow_none=True,
+            desc="get_user_by_external_id",
+        )
+
+    @defer.inlineCallbacks
+    def count_all_users(self):
+        """Counts all users registered on the homeserver."""
+
+        def _count_users(txn):
+            txn.execute("SELECT COUNT(*) AS users FROM users")
+            rows = self.db_pool.cursor_to_dict(txn)
+            if rows:
+                return rows[0]["users"]
+            return 0
+
+        ret = yield self.db_pool.runInteraction("count_users", _count_users)
+        return ret
+
+    def count_daily_user_type(self):
+        """
+        Counts 1) native non guest users
+               2) native guests users
+               3) bridged users
+        who registered on the homeserver in the past 24 hours
+        """
+
+        def _count_daily_user_type(txn):
+            yesterday = int(self._clock.time()) - (60 * 60 * 24)
+
+            sql = """
+                SELECT user_type, COALESCE(count(*), 0) AS count FROM (
+                    SELECT
+                    CASE
+                        WHEN is_guest=0 AND appservice_id IS NULL THEN 'native'
+                        WHEN is_guest=1 AND appservice_id IS NULL THEN 'guest'
+                        WHEN is_guest=0 AND appservice_id IS NOT NULL THEN 'bridged'
+                    END AS user_type
+                    FROM users
+                    WHERE creation_ts > ?
+                ) AS t GROUP BY user_type
+            """
+            results = {"native": 0, "guest": 0, "bridged": 0}
+            txn.execute(sql, (yesterday,))
+            for row in txn:
+                results[row[0]] = row[1]
+            return results
+
+        return self.db_pool.runInteraction(
+            "count_daily_user_type", _count_daily_user_type
+        )
+
+    @defer.inlineCallbacks
+    def count_nonbridged_users(self):
+        def _count_users(txn):
+            txn.execute(
+                """
+                SELECT COALESCE(COUNT(*), 0) FROM users
+                WHERE appservice_id IS NULL
+            """
+            )
+            (count,) = txn.fetchone()
+            return count
+
+        ret = yield self.db_pool.runInteraction("count_users", _count_users)
+        return ret
+
+    @defer.inlineCallbacks
+    def count_real_users(self):
+        """Counts all users without a special user_type registered on the homeserver."""
+
+        def _count_users(txn):
+            txn.execute("SELECT COUNT(*) AS users FROM users where user_type is null")
+            rows = self.db_pool.cursor_to_dict(txn)
+            if rows:
+                return rows[0]["users"]
+            return 0
+
+        ret = yield self.db_pool.runInteraction("count_real_users", _count_users)
+        return ret
+
+    async def generate_user_id(self) -> str:
+        """Generate a suitable localpart for a guest user
+
+        Returns: a (hopefully) free localpart
+        """
+        next_id = await self.db_pool.runInteraction(
+            "generate_user_id", self._user_id_seq.get_next_id_txn
+        )
+
+        return str(next_id)
+
+    async def get_user_id_by_threepid(self, medium: str, address: str) -> Optional[str]:
+        """Returns user id from threepid
+
+        Args:
+            medium: threepid medium e.g. email
+            address: threepid address e.g. me@example.com
+
+        Returns:
+            The user ID or None if no user id/threepid mapping exists
+        """
+        user_id = await self.db_pool.runInteraction(
+            "get_user_id_by_threepid", self.get_user_id_by_threepid_txn, medium, address
+        )
+        return user_id
+
+    def get_user_id_by_threepid_txn(self, txn, medium, address):
+        """Returns user id from threepid
+
+        Args:
+            txn (cursor):
+            medium (str): threepid medium e.g. email
+            address (str): threepid address e.g. me@example.com
+
+        Returns:
+            str|None: user id or None if no user id/threepid mapping exists
+        """
+        ret = self.db_pool.simple_select_one_txn(
+            txn,
+            "user_threepids",
+            {"medium": medium, "address": address},
+            ["user_id"],
+            True,
+        )
+        if ret:
+            return ret["user_id"]
+        return None
+
+    @defer.inlineCallbacks
+    def user_add_threepid(self, user_id, medium, address, validated_at, added_at):
+        yield self.db_pool.simple_upsert(
+            "user_threepids",
+            {"medium": medium, "address": address},
+            {"user_id": user_id, "validated_at": validated_at, "added_at": added_at},
+        )
+
+    @defer.inlineCallbacks
+    def user_get_threepids(self, user_id):
+        ret = yield self.db_pool.simple_select_list(
+            "user_threepids",
+            {"user_id": user_id},
+            ["medium", "address", "validated_at", "added_at"],
+            "user_get_threepids",
+        )
+        return ret
+
+    def user_delete_threepid(self, user_id, medium, address):
+        return self.db_pool.simple_delete(
+            "user_threepids",
+            keyvalues={"user_id": user_id, "medium": medium, "address": address},
+            desc="user_delete_threepid",
+        )
+
+    def user_delete_threepids(self, user_id: str):
+        """Delete all threepid this user has bound
+
+        Args:
+             user_id: The user id to delete all threepids of
+
+        """
+        return self.db_pool.simple_delete(
+            "user_threepids",
+            keyvalues={"user_id": user_id},
+            desc="user_delete_threepids",
+        )
+
+    def add_user_bound_threepid(self, user_id, medium, address, id_server):
+        """The server proxied a bind request to the given identity server on
+        behalf of the given user. We need to remember this in case the user
+        asks us to unbind the threepid.
+
+        Args:
+            user_id (str)
+            medium (str)
+            address (str)
+            id_server (str)
+
+        Returns:
+            Deferred
+        """
+        # We need to use an upsert, in case they user had already bound the
+        # threepid
+        return self.db_pool.simple_upsert(
+            table="user_threepid_id_server",
+            keyvalues={
+                "user_id": user_id,
+                "medium": medium,
+                "address": address,
+                "id_server": id_server,
+            },
+            values={},
+            insertion_values={},
+            desc="add_user_bound_threepid",
+        )
+
+    def user_get_bound_threepids(self, user_id):
+        """Get the threepids that a user has bound to an identity server through the homeserver
+        The homeserver remembers where binds to an identity server occurred. Using this
+        method can retrieve those threepids.
+
+        Args:
+            user_id (str): The ID of the user to retrieve threepids for
+
+        Returns:
+            Deferred[list[dict]]: List of dictionaries containing the following:
+                medium (str): The medium of the threepid (e.g "email")
+                address (str): The address of the threepid (e.g "bob@example.com")
+        """
+        return self.db_pool.simple_select_list(
+            table="user_threepid_id_server",
+            keyvalues={"user_id": user_id},
+            retcols=["medium", "address"],
+            desc="user_get_bound_threepids",
+        )
+
+    def remove_user_bound_threepid(self, user_id, medium, address, id_server):
+        """The server proxied an unbind request to the given identity server on
+        behalf of the given user, so we remove the mapping of threepid to
+        identity server.
+
+        Args:
+            user_id (str)
+            medium (str)
+            address (str)
+            id_server (str)
+
+        Returns:
+            Deferred
+        """
+        return self.db_pool.simple_delete(
+            table="user_threepid_id_server",
+            keyvalues={
+                "user_id": user_id,
+                "medium": medium,
+                "address": address,
+                "id_server": id_server,
+            },
+            desc="remove_user_bound_threepid",
+        )
+
+    def get_id_servers_user_bound(self, user_id, medium, address):
+        """Get the list of identity servers that the server proxied bind
+        requests to for given user and threepid
+
+        Args:
+            user_id (str)
+            medium (str)
+            address (str)
+
+        Returns:
+            Deferred[list[str]]: Resolves to a list of identity servers
+        """
+        return self.db_pool.simple_select_onecol(
+            table="user_threepid_id_server",
+            keyvalues={"user_id": user_id, "medium": medium, "address": address},
+            retcol="id_server",
+            desc="get_id_servers_user_bound",
+        )
+
+    @cachedInlineCallbacks()
+    def get_user_deactivated_status(self, user_id):
+        """Retrieve the value for the `deactivated` property for the provided user.
+
+        Args:
+            user_id (str): The ID of the user to retrieve the status for.
+
+        Returns:
+            defer.Deferred(bool): The requested value.
+        """
+
+        res = yield self.db_pool.simple_select_one_onecol(
+            table="users",
+            keyvalues={"name": user_id},
+            retcol="deactivated",
+            desc="get_user_deactivated_status",
+        )
+
+        # Convert the integer into a boolean.
+        return res == 1
+
+    def get_threepid_validation_session(
+        self, medium, client_secret, address=None, sid=None, validated=True
+    ):
+        """Gets a session_id and last_send_attempt (if available) for a
+        combination of validation metadata
+
+        Args:
+            medium (str|None): The medium of the 3PID
+            address (str|None): The address of the 3PID
+            sid (str|None): The ID of the validation session
+            client_secret (str): A unique string provided by the client to help identify this
+                validation attempt
+            validated (bool|None): Whether sessions should be filtered by
+                whether they have been validated already or not. None to
+                perform no filtering
+
+        Returns:
+            Deferred[dict|None]: A dict containing the following:
+                * address - address of the 3pid
+                * medium - medium of the 3pid
+                * client_secret - a secret provided by the client for this validation session
+                * session_id - ID of the validation session
+                * send_attempt - a number serving to dedupe send attempts for this session
+                * validated_at - timestamp of when this session was validated if so
+
+                Otherwise None if a validation session is not found
+        """
+        if not client_secret:
+            raise SynapseError(
+                400, "Missing parameter: client_secret", errcode=Codes.MISSING_PARAM
+            )
+
+        keyvalues = {"client_secret": client_secret}
+        if medium:
+            keyvalues["medium"] = medium
+        if address:
+            keyvalues["address"] = address
+        if sid:
+            keyvalues["session_id"] = sid
+
+        assert address or sid
+
+        def get_threepid_validation_session_txn(txn):
+            sql = """
+                SELECT address, session_id, medium, client_secret,
+                last_send_attempt, validated_at
+                FROM threepid_validation_session WHERE %s
+                """ % (
+                " AND ".join("%s = ?" % k for k in keyvalues.keys()),
+            )
+
+            if validated is not None:
+                sql += " AND validated_at IS " + ("NOT NULL" if validated else "NULL")
+
+            sql += " LIMIT 1"
+
+            txn.execute(sql, list(keyvalues.values()))
+            rows = self.db_pool.cursor_to_dict(txn)
+            if not rows:
+                return None
+
+            return rows[0]
+
+        return self.db_pool.runInteraction(
+            "get_threepid_validation_session", get_threepid_validation_session_txn
+        )
+
+    def delete_threepid_session(self, session_id):
+        """Removes a threepid validation session from the database. This can
+        be done after validation has been performed and whatever action was
+        waiting on it has been carried out
+
+        Args:
+            session_id (str): The ID of the session to delete
+        """
+
+        def delete_threepid_session_txn(txn):
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="threepid_validation_token",
+                keyvalues={"session_id": session_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="threepid_validation_session",
+                keyvalues={"session_id": session_id},
+            )
+
+        return self.db_pool.runInteraction(
+            "delete_threepid_session", delete_threepid_session_txn
+        )
+
+
+class RegistrationBackgroundUpdateStore(RegistrationWorkerStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RegistrationBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        self.clock = hs.get_clock()
+        self.config = hs.config
+
+        self.db_pool.updates.register_background_index_update(
+            "access_tokens_device_index",
+            index_name="access_tokens_device_id",
+            table="access_tokens",
+            columns=["user_id", "device_id"],
+        )
+
+        self.db_pool.updates.register_background_index_update(
+            "users_creation_ts",
+            index_name="users_creation_ts",
+            table="users",
+            columns=["creation_ts"],
+        )
+
+        # we no longer use refresh tokens, but it's possible that some people
+        # might have a background update queued to build this index. Just
+        # clear the background update.
+        self.db_pool.updates.register_noop_background_update(
+            "refresh_tokens_device_index"
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            "user_threepids_grandfather", self._bg_user_threepids_grandfather
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            "users_set_deactivated_flag", self._background_update_set_deactivated_flag
+        )
+
+    @defer.inlineCallbacks
+    def _background_update_set_deactivated_flag(self, progress, batch_size):
+        """Retrieves a list of all deactivated users and sets the 'deactivated' flag to 1
+        for each of them.
+        """
+
+        last_user = progress.get("user_id", "")
+
+        def _background_update_set_deactivated_flag_txn(txn):
+            txn.execute(
+                """
+                SELECT
+                    users.name,
+                    COUNT(access_tokens.token) AS count_tokens,
+                    COUNT(user_threepids.address) AS count_threepids
+                FROM users
+                    LEFT JOIN access_tokens ON (access_tokens.user_id = users.name)
+                    LEFT JOIN user_threepids ON (user_threepids.user_id = users.name)
+                WHERE (users.password_hash IS NULL OR users.password_hash = '')
+                AND (users.appservice_id IS NULL OR users.appservice_id = '')
+                AND users.is_guest = 0
+                AND users.name > ?
+                GROUP BY users.name
+                ORDER BY users.name ASC
+                LIMIT ?;
+                """,
+                (last_user, batch_size),
+            )
+
+            rows = self.db_pool.cursor_to_dict(txn)
+
+            if not rows:
+                return True, 0
+
+            rows_processed_nb = 0
+
+            for user in rows:
+                if not user["count_tokens"] and not user["count_threepids"]:
+                    self.set_user_deactivated_status_txn(txn, user["name"], True)
+                    rows_processed_nb += 1
+
+            logger.info("Marked %d rows as deactivated", rows_processed_nb)
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, "users_set_deactivated_flag", {"user_id": rows[-1]["name"]}
+            )
+
+            if batch_size > len(rows):
+                return True, len(rows)
+            else:
+                return False, len(rows)
+
+        end, nb_processed = yield self.db_pool.runInteraction(
+            "users_set_deactivated_flag", _background_update_set_deactivated_flag_txn
+        )
+
+        if end:
+            yield self.db_pool.updates._end_background_update(
+                "users_set_deactivated_flag"
+            )
+
+        return nb_processed
+
+    @defer.inlineCallbacks
+    def _bg_user_threepids_grandfather(self, progress, batch_size):
+        """We now track which identity servers a user binds their 3PID to, so
+        we need to handle the case of existing bindings where we didn't track
+        this.
+
+        We do this by grandfathering in existing user threepids assuming that
+        they used one of the server configured trusted identity servers.
+        """
+        id_servers = set(self.config.trusted_third_party_id_servers)
+
+        def _bg_user_threepids_grandfather_txn(txn):
+            sql = """
+                INSERT INTO user_threepid_id_server
+                    (user_id, medium, address, id_server)
+                SELECT user_id, medium, address, ?
+                FROM user_threepids
+            """
+
+            txn.executemany(sql, [(id_server,) for id_server in id_servers])
+
+        if id_servers:
+            yield self.db_pool.runInteraction(
+                "_bg_user_threepids_grandfather", _bg_user_threepids_grandfather_txn
+            )
+
+        yield self.db_pool.updates._end_background_update("user_threepids_grandfather")
+
+        return 1
+
+
+class RegistrationStore(RegistrationBackgroundUpdateStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RegistrationStore, self).__init__(database, db_conn, hs)
+
+        self._account_validity = hs.config.account_validity
+
+        if self._account_validity.enabled:
+            self._clock.call_later(
+                0.0,
+                run_as_background_process,
+                "account_validity_set_expiration_dates",
+                self._set_expiration_date_when_missing,
+            )
+
+        # Create a background job for culling expired 3PID validity tokens
+        def start_cull():
+            # run as a background process to make sure that the database transactions
+            # have a logcontext to report to
+            return run_as_background_process(
+                "cull_expired_threepid_validation_tokens",
+                self.cull_expired_threepid_validation_tokens,
+            )
+
+        hs.get_clock().looping_call(start_cull, THIRTY_MINUTES_IN_MS)
+
+    @defer.inlineCallbacks
+    def add_access_token_to_user(self, user_id, token, device_id, valid_until_ms):
+        """Adds an access token for the given user.
+
+        Args:
+            user_id (str): The user ID.
+            token (str): The new access token to add.
+            device_id (str): ID of the device to associate with the access
+                token
+            valid_until_ms (int|None): when the token is valid until. None for
+                no expiry.
+        Raises:
+            StoreError if there was a problem adding this.
+        """
+        next_id = self._access_tokens_id_gen.get_next()
+
+        yield self.db_pool.simple_insert(
+            "access_tokens",
+            {
+                "id": next_id,
+                "user_id": user_id,
+                "token": token,
+                "device_id": device_id,
+                "valid_until_ms": valid_until_ms,
+            },
+            desc="add_access_token_to_user",
+        )
+
+    def register_user(
+        self,
+        user_id,
+        password_hash=None,
+        was_guest=False,
+        make_guest=False,
+        appservice_id=None,
+        create_profile_with_displayname=None,
+        admin=False,
+        user_type=None,
+    ):
+        """Attempts to register an account.
+
+        Args:
+            user_id (str): The desired user ID to register.
+            password_hash (str|None): Optional. The password hash for this user.
+            was_guest (bool): Optional. Whether this is a guest account being
+                upgraded to a non-guest account.
+            make_guest (boolean): True if the the new user should be guest,
+                false to add a regular user account.
+            appservice_id (str): The ID of the appservice registering the user.
+            create_profile_with_displayname (unicode): Optionally create a profile for
+                the user, setting their displayname to the given value
+            admin (boolean): is an admin user?
+            user_type (str|None): type of user. One of the values from
+                api.constants.UserTypes, or None for a normal user.
+
+        Raises:
+            StoreError if the user_id could not be registered.
+
+        Returns:
+            Deferred
+        """
+        return self.db_pool.runInteraction(
+            "register_user",
+            self._register_user,
+            user_id,
+            password_hash,
+            was_guest,
+            make_guest,
+            appservice_id,
+            create_profile_with_displayname,
+            admin,
+            user_type,
+        )
+
+    def _register_user(
+        self,
+        txn,
+        user_id,
+        password_hash,
+        was_guest,
+        make_guest,
+        appservice_id,
+        create_profile_with_displayname,
+        admin,
+        user_type,
+    ):
+        user_id_obj = UserID.from_string(user_id)
+
+        now = int(self.clock.time())
+
+        try:
+            if was_guest:
+                # Ensure that the guest user actually exists
+                # ``allow_none=False`` makes this raise an exception
+                # if the row isn't in the database.
+                self.db_pool.simple_select_one_txn(
+                    txn,
+                    "users",
+                    keyvalues={"name": user_id, "is_guest": 1},
+                    retcols=("name",),
+                    allow_none=False,
+                )
+
+                self.db_pool.simple_update_one_txn(
+                    txn,
+                    "users",
+                    keyvalues={"name": user_id, "is_guest": 1},
+                    updatevalues={
+                        "password_hash": password_hash,
+                        "upgrade_ts": now,
+                        "is_guest": 1 if make_guest else 0,
+                        "appservice_id": appservice_id,
+                        "admin": 1 if admin else 0,
+                        "user_type": user_type,
+                    },
+                )
+            else:
+                self.db_pool.simple_insert_txn(
+                    txn,
+                    "users",
+                    values={
+                        "name": user_id,
+                        "password_hash": password_hash,
+                        "creation_ts": now,
+                        "is_guest": 1 if make_guest else 0,
+                        "appservice_id": appservice_id,
+                        "admin": 1 if admin else 0,
+                        "user_type": user_type,
+                    },
+                )
+
+        except self.database_engine.module.IntegrityError:
+            raise StoreError(400, "User ID already taken.", errcode=Codes.USER_IN_USE)
+
+        if self._account_validity.enabled:
+            self.set_expiration_date_for_user_txn(txn, user_id)
+
+        if create_profile_with_displayname:
+            # set a default displayname serverside to avoid ugly race
+            # between auto-joins and clients trying to set displaynames
+            #
+            # *obviously* the 'profiles' table uses localpart for user_id
+            # while everything else uses the full mxid.
+            txn.execute(
+                "INSERT INTO profiles(user_id, displayname) VALUES (?,?)",
+                (user_id_obj.localpart, create_profile_with_displayname),
+            )
+
+        if self.hs.config.stats_enabled:
+            # we create a new completed user statistics row
+
+            # we don't strictly need current_token since this user really can't
+            # have any state deltas before now (as it is a new user), but still,
+            # we include it for completeness.
+            current_token = self._get_max_stream_id_in_current_state_deltas_txn(txn)
+            self._update_stats_delta_txn(
+                txn, now, "user", user_id, {}, complete_with_stream_id=current_token
+            )
+
+        self._invalidate_cache_and_stream(txn, self.get_user_by_id, (user_id,))
+        txn.call_after(self.is_guest.invalidate, (user_id,))
+
+    def record_user_external_id(
+        self, auth_provider: str, external_id: str, user_id: str
+    ) -> Deferred:
+        """Record a mapping from an external user id to a mxid
+
+        Args:
+            auth_provider: identifier for the remote auth provider
+            external_id: id on that system
+            user_id: complete mxid that it is mapped to
+        """
+        return self.db_pool.simple_insert(
+            table="user_external_ids",
+            values={
+                "auth_provider": auth_provider,
+                "external_id": external_id,
+                "user_id": user_id,
+            },
+            desc="record_user_external_id",
+        )
+
+    def user_set_password_hash(self, user_id, password_hash):
+        """
+        NB. This does *not* evict any cache because the one use for this
+            removes most of the entries subsequently anyway so it would be
+            pointless. Use flush_user separately.
+        """
+
+        def user_set_password_hash_txn(txn):
+            self.db_pool.simple_update_one_txn(
+                txn, "users", {"name": user_id}, {"password_hash": password_hash}
+            )
+            self._invalidate_cache_and_stream(txn, self.get_user_by_id, (user_id,))
+
+        return self.db_pool.runInteraction(
+            "user_set_password_hash", user_set_password_hash_txn
+        )
+
+    def user_set_consent_version(self, user_id, consent_version):
+        """Updates the user table to record privacy policy consent
+
+        Args:
+            user_id (str): full mxid of the user to update
+            consent_version (str): version of the policy the user has consented
+                to
+
+        Raises:
+            StoreError(404) if user not found
+        """
+
+        def f(txn):
+            self.db_pool.simple_update_one_txn(
+                txn,
+                table="users",
+                keyvalues={"name": user_id},
+                updatevalues={"consent_version": consent_version},
+            )
+            self._invalidate_cache_and_stream(txn, self.get_user_by_id, (user_id,))
+
+        return self.db_pool.runInteraction("user_set_consent_version", f)
+
+    def user_set_consent_server_notice_sent(self, user_id, consent_version):
+        """Updates the user table to record that we have sent the user a server
+        notice about privacy policy consent
+
+        Args:
+            user_id (str): full mxid of the user to update
+            consent_version (str): version of the policy we have notified the
+                user about
+
+        Raises:
+            StoreError(404) if user not found
+        """
+
+        def f(txn):
+            self.db_pool.simple_update_one_txn(
+                txn,
+                table="users",
+                keyvalues={"name": user_id},
+                updatevalues={"consent_server_notice_sent": consent_version},
+            )
+            self._invalidate_cache_and_stream(txn, self.get_user_by_id, (user_id,))
+
+        return self.db_pool.runInteraction("user_set_consent_server_notice_sent", f)
+
+    def user_delete_access_tokens(self, user_id, except_token_id=None, device_id=None):
+        """
+        Invalidate access tokens belonging to a user
+
+        Args:
+            user_id (str):  ID of user the tokens belong to
+            except_token_id (str): list of access_tokens IDs which should
+                *not* be deleted
+            device_id (str|None):  ID of device the tokens are associated with.
+                If None, tokens associated with any device (or no device) will
+                be deleted
+        Returns:
+            defer.Deferred[list[str, int, str|None, int]]: a list of
+                (token, token id, device id) for each of the deleted tokens
+        """
+
+        def f(txn):
+            keyvalues = {"user_id": user_id}
+            if device_id is not None:
+                keyvalues["device_id"] = device_id
+
+            items = keyvalues.items()
+            where_clause = " AND ".join(k + " = ?" for k, _ in items)
+            values = [v for _, v in items]
+            if except_token_id:
+                where_clause += " AND id != ?"
+                values.append(except_token_id)
+
+            txn.execute(
+                "SELECT token, id, device_id FROM access_tokens WHERE %s"
+                % where_clause,
+                values,
+            )
+            tokens_and_devices = [(r[0], r[1], r[2]) for r in txn]
+
+            for token, _, _ in tokens_and_devices:
+                self._invalidate_cache_and_stream(
+                    txn, self.get_user_by_access_token, (token,)
+                )
+
+            txn.execute("DELETE FROM access_tokens WHERE %s" % where_clause, values)
+
+            return tokens_and_devices
+
+        return self.db_pool.runInteraction("user_delete_access_tokens", f)
+
+    def delete_access_token(self, access_token):
+        def f(txn):
+            self.db_pool.simple_delete_one_txn(
+                txn, table="access_tokens", keyvalues={"token": access_token}
+            )
+
+            self._invalidate_cache_and_stream(
+                txn, self.get_user_by_access_token, (access_token,)
+            )
+
+        return self.db_pool.runInteraction("delete_access_token", f)
+
+    @cachedInlineCallbacks()
+    def is_guest(self, user_id):
+        res = yield self.db_pool.simple_select_one_onecol(
+            table="users",
+            keyvalues={"name": user_id},
+            retcol="is_guest",
+            allow_none=True,
+            desc="is_guest",
+        )
+
+        return res if res else False
+
+    def add_user_pending_deactivation(self, user_id):
+        """
+        Adds a user to the table of users who need to be parted from all the rooms they're
+        in
+        """
+        return self.db_pool.simple_insert(
+            "users_pending_deactivation",
+            values={"user_id": user_id},
+            desc="add_user_pending_deactivation",
+        )
+
+    def del_user_pending_deactivation(self, user_id):
+        """
+        Removes the given user to the table of users who need to be parted from all the
+        rooms they're in, effectively marking that user as fully deactivated.
+        """
+        # XXX: This should be simple_delete_one but we failed to put a unique index on
+        # the table, so somehow duplicate entries have ended up in it.
+        return self.db_pool.simple_delete(
+            "users_pending_deactivation",
+            keyvalues={"user_id": user_id},
+            desc="del_user_pending_deactivation",
+        )
+
+    def get_user_pending_deactivation(self):
+        """
+        Gets one user from the table of users waiting to be parted from all the rooms
+        they're in.
+        """
+        return self.db_pool.simple_select_one_onecol(
+            "users_pending_deactivation",
+            keyvalues={},
+            retcol="user_id",
+            allow_none=True,
+            desc="get_users_pending_deactivation",
+        )
+
+    def validate_threepid_session(self, session_id, client_secret, token, current_ts):
+        """Attempt to validate a threepid session using a token
+
+        Args:
+            session_id (str): The id of a validation session
+            client_secret (str): A unique string provided by the client to
+                help identify this validation attempt
+            token (str): A validation token
+            current_ts (int): The current unix time in milliseconds. Used for
+                checking token expiry status
+
+        Raises:
+            ThreepidValidationError: if a matching validation token was not found or has
+                expired
+
+        Returns:
+            deferred str|None: A str representing a link to redirect the user
+            to if there is one.
+        """
+
+        # Insert everything into a transaction in order to run atomically
+        def validate_threepid_session_txn(txn):
+            row = self.db_pool.simple_select_one_txn(
+                txn,
+                table="threepid_validation_session",
+                keyvalues={"session_id": session_id},
+                retcols=["client_secret", "validated_at"],
+                allow_none=True,
+            )
+
+            if not row:
+                raise ThreepidValidationError(400, "Unknown session_id")
+            retrieved_client_secret = row["client_secret"]
+            validated_at = row["validated_at"]
+
+            if retrieved_client_secret != client_secret:
+                raise ThreepidValidationError(
+                    400, "This client_secret does not match the provided session_id"
+                )
+
+            row = self.db_pool.simple_select_one_txn(
+                txn,
+                table="threepid_validation_token",
+                keyvalues={"session_id": session_id, "token": token},
+                retcols=["expires", "next_link"],
+                allow_none=True,
+            )
+
+            if not row:
+                raise ThreepidValidationError(
+                    400, "Validation token not found or has expired"
+                )
+            expires = row["expires"]
+            next_link = row["next_link"]
+
+            # If the session is already validated, no need to revalidate
+            if validated_at:
+                return next_link
+
+            if expires <= current_ts:
+                raise ThreepidValidationError(
+                    400, "This token has expired. Please request a new one"
+                )
+
+            # Looks good. Validate the session
+            self.db_pool.simple_update_txn(
+                txn,
+                table="threepid_validation_session",
+                keyvalues={"session_id": session_id},
+                updatevalues={"validated_at": self.clock.time_msec()},
+            )
+
+            return next_link
+
+        # Return next_link if it exists
+        return self.db_pool.runInteraction(
+            "validate_threepid_session_txn", validate_threepid_session_txn
+        )
+
+    def upsert_threepid_validation_session(
+        self,
+        medium,
+        address,
+        client_secret,
+        send_attempt,
+        session_id,
+        validated_at=None,
+    ):
+        """Upsert a threepid validation session
+        Args:
+            medium (str): The medium of the 3PID
+            address (str): The address of the 3PID
+            client_secret (str): A unique string provided by the client to
+                help identify this validation attempt
+            send_attempt (int): The latest send_attempt on this session
+            session_id (str): The id of this validation session
+            validated_at (int|None): The unix timestamp in milliseconds of
+                when the session was marked as valid
+        """
+        insertion_values = {
+            "medium": medium,
+            "address": address,
+            "client_secret": client_secret,
+        }
+
+        if validated_at:
+            insertion_values["validated_at"] = validated_at
+
+        return self.db_pool.simple_upsert(
+            table="threepid_validation_session",
+            keyvalues={"session_id": session_id},
+            values={"last_send_attempt": send_attempt},
+            insertion_values=insertion_values,
+            desc="upsert_threepid_validation_session",
+        )
+
+    def start_or_continue_validation_session(
+        self,
+        medium,
+        address,
+        session_id,
+        client_secret,
+        send_attempt,
+        next_link,
+        token,
+        token_expires,
+    ):
+        """Creates a new threepid validation session if it does not already
+        exist and associates a new validation token with it
+
+        Args:
+            medium (str): The medium of the 3PID
+            address (str): The address of the 3PID
+            session_id (str): The id of this validation session
+            client_secret (str): A unique string provided by the client to
+                help identify this validation attempt
+            send_attempt (int): The latest send_attempt on this session
+            next_link (str|None): The link to redirect the user to upon
+                successful validation
+            token (str): The validation token
+            token_expires (int): The timestamp for which after the token
+                will no longer be valid
+        """
+
+        def start_or_continue_validation_session_txn(txn):
+            # Create or update a validation session
+            self.db_pool.simple_upsert_txn(
+                txn,
+                table="threepid_validation_session",
+                keyvalues={"session_id": session_id},
+                values={"last_send_attempt": send_attempt},
+                insertion_values={
+                    "medium": medium,
+                    "address": address,
+                    "client_secret": client_secret,
+                },
+            )
+
+            # Create a new validation token with this session ID
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="threepid_validation_token",
+                values={
+                    "session_id": session_id,
+                    "token": token,
+                    "next_link": next_link,
+                    "expires": token_expires,
+                },
+            )
+
+        return self.db_pool.runInteraction(
+            "start_or_continue_validation_session",
+            start_or_continue_validation_session_txn,
+        )
+
+    def cull_expired_threepid_validation_tokens(self):
+        """Remove threepid validation tokens with expiry dates that have passed"""
+
+        def cull_expired_threepid_validation_tokens_txn(txn, ts):
+            sql = """
+            DELETE FROM threepid_validation_token WHERE
+            expires < ?
+            """
+            return txn.execute(sql, (ts,))
+
+        return self.db_pool.runInteraction(
+            "cull_expired_threepid_validation_tokens",
+            cull_expired_threepid_validation_tokens_txn,
+            self.clock.time_msec(),
+        )
+
+    @defer.inlineCallbacks
+    def set_user_deactivated_status(self, user_id, deactivated):
+        """Set the `deactivated` property for the provided user to the provided value.
+
+        Args:
+            user_id (str): The ID of the user to set the status for.
+            deactivated (bool): The value to set for `deactivated`.
+        """
+
+        yield self.db_pool.runInteraction(
+            "set_user_deactivated_status",
+            self.set_user_deactivated_status_txn,
+            user_id,
+            deactivated,
+        )
+
+    def set_user_deactivated_status_txn(self, txn, user_id, deactivated):
+        self.db_pool.simple_update_one_txn(
+            txn=txn,
+            table="users",
+            keyvalues={"name": user_id},
+            updatevalues={"deactivated": 1 if deactivated else 0},
+        )
+        self._invalidate_cache_and_stream(
+            txn, self.get_user_deactivated_status, (user_id,)
+        )
+
+    @defer.inlineCallbacks
+    def _set_expiration_date_when_missing(self):
+        """
+        Retrieves the list of registered users that don't have an expiration date, and
+        adds an expiration date for each of them.
+        """
+
+        def select_users_with_no_expiration_date_txn(txn):
+            """Retrieves the list of registered users with no expiration date from the
+            database, filtering out deactivated users.
+            """
+            sql = (
+                "SELECT users.name FROM users"
+                " LEFT JOIN account_validity ON (users.name = account_validity.user_id)"
+                " WHERE account_validity.user_id is NULL AND users.deactivated = 0;"
+            )
+            txn.execute(sql, [])
+
+            res = self.db_pool.cursor_to_dict(txn)
+            if res:
+                for user in res:
+                    self.set_expiration_date_for_user_txn(
+                        txn, user["name"], use_delta=True
+                    )
+
+        yield self.db_pool.runInteraction(
+            "get_users_with_no_expiration_date",
+            select_users_with_no_expiration_date_txn,
+        )
+
+    def set_expiration_date_for_user_txn(self, txn, user_id, use_delta=False):
+        """Sets an expiration date to the account with the given user ID.
+
+        Args:
+             user_id (str): User ID to set an expiration date for.
+             use_delta (bool): If set to False, the expiration date for the user will be
+                now + validity period. If set to True, this expiration date will be a
+                random value in the [now + period - d ; now + period] range, d being a
+                delta equal to 10% of the validity period.
+        """
+        now_ms = self._clock.time_msec()
+        expiration_ts = now_ms + self._account_validity.period
+
+        if use_delta:
+            expiration_ts = self.rand.randrange(
+                expiration_ts - self._account_validity.startup_job_max_delta,
+                expiration_ts,
+            )
+
+        self.db_pool.simple_upsert_txn(
+            txn,
+            "account_validity",
+            keyvalues={"user_id": user_id},
+            values={"expiration_ts_ms": expiration_ts, "email_sent": False},
+        )
+
+
+def find_max_generated_user_id_localpart(cur: Cursor) -> int:
+    """
+    Gets the localpart of the max current generated user ID.
+
+    Generated user IDs are integers, so we find the largest integer user ID
+    already taken and return that.
+    """
+
+    # We bound between '@0' and '@a' to avoid pulling the entire table
+    # out.
+    cur.execute("SELECT name FROM users WHERE '@0' <= name AND name < '@a'")
+
+    regex = re.compile(r"^@(\d+):")
+
+    max_found = 0
+
+    for (user_id,) in cur:
+        match = regex.search(user_id)
+        if match:
+            max_found = max(int(match.group(1)), max_found)
+    return max_found
diff --git a/synapse/storage/databases/main/rejections.py b/synapse/storage/databases/main/rejections.py
new file mode 100644
index 0000000000..cf9ba51205
--- /dev/null
+++ b/synapse/storage/databases/main/rejections.py
@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from synapse.storage._base import SQLBaseStore
+
+logger = logging.getLogger(__name__)
+
+
+class RejectionsStore(SQLBaseStore):
+    def get_rejection_reason(self, event_id):
+        return self.db_pool.simple_select_one_onecol(
+            table="rejections",
+            retcol="reason",
+            keyvalues={"event_id": event_id},
+            allow_none=True,
+            desc="get_rejection_reason",
+        )
diff --git a/synapse/storage/databases/main/relations.py b/synapse/storage/databases/main/relations.py
new file mode 100644
index 0000000000..b81f1449b7
--- /dev/null
+++ b/synapse/storage/databases/main/relations.py
@@ -0,0 +1,327 @@
+# -*- coding: utf-8 -*-
+# Copyright 2019 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+import attr
+
+from synapse.api.constants import RelationTypes
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.databases.main.stream import generate_pagination_where_clause
+from synapse.storage.relations import (
+    AggregationPaginationToken,
+    PaginationChunk,
+    RelationPaginationToken,
+)
+from synapse.util.caches.descriptors import cached, cachedInlineCallbacks
+
+logger = logging.getLogger(__name__)
+
+
+class RelationsWorkerStore(SQLBaseStore):
+    @cached(tree=True)
+    def get_relations_for_event(
+        self,
+        event_id,
+        relation_type=None,
+        event_type=None,
+        aggregation_key=None,
+        limit=5,
+        direction="b",
+        from_token=None,
+        to_token=None,
+    ):
+        """Get a list of relations for an event, ordered by topological ordering.
+
+        Args:
+            event_id (str): Fetch events that relate to this event ID.
+            relation_type (str|None): Only fetch events with this relation
+                type, if given.
+            event_type (str|None): Only fetch events with this event type, if
+                given.
+            aggregation_key (str|None): Only fetch events with this aggregation
+                key, if given.
+            limit (int): Only fetch the most recent `limit` events.
+            direction (str): Whether to fetch the most recent first (`"b"`) or
+                the oldest first (`"f"`).
+            from_token (RelationPaginationToken|None): Fetch rows from the given
+                token, or from the start if None.
+            to_token (RelationPaginationToken|None): Fetch rows up to the given
+                token, or up to the end if None.
+
+        Returns:
+            Deferred[PaginationChunk]: List of event IDs that match relations
+            requested. The rows are of the form `{"event_id": "..."}`.
+        """
+
+        where_clause = ["relates_to_id = ?"]
+        where_args = [event_id]
+
+        if relation_type is not None:
+            where_clause.append("relation_type = ?")
+            where_args.append(relation_type)
+
+        if event_type is not None:
+            where_clause.append("type = ?")
+            where_args.append(event_type)
+
+        if aggregation_key:
+            where_clause.append("aggregation_key = ?")
+            where_args.append(aggregation_key)
+
+        pagination_clause = generate_pagination_where_clause(
+            direction=direction,
+            column_names=("topological_ordering", "stream_ordering"),
+            from_token=attr.astuple(from_token) if from_token else None,
+            to_token=attr.astuple(to_token) if to_token else None,
+            engine=self.database_engine,
+        )
+
+        if pagination_clause:
+            where_clause.append(pagination_clause)
+
+        if direction == "b":
+            order = "DESC"
+        else:
+            order = "ASC"
+
+        sql = """
+            SELECT event_id, topological_ordering, stream_ordering
+            FROM event_relations
+            INNER JOIN events USING (event_id)
+            WHERE %s
+            ORDER BY topological_ordering %s, stream_ordering %s
+            LIMIT ?
+        """ % (
+            " AND ".join(where_clause),
+            order,
+            order,
+        )
+
+        def _get_recent_references_for_event_txn(txn):
+            txn.execute(sql, where_args + [limit + 1])
+
+            last_topo_id = None
+            last_stream_id = None
+            events = []
+            for row in txn:
+                events.append({"event_id": row[0]})
+                last_topo_id = row[1]
+                last_stream_id = row[2]
+
+            next_batch = None
+            if len(events) > limit and last_topo_id and last_stream_id:
+                next_batch = RelationPaginationToken(last_topo_id, last_stream_id)
+
+            return PaginationChunk(
+                chunk=list(events[:limit]), next_batch=next_batch, prev_batch=from_token
+            )
+
+        return self.db_pool.runInteraction(
+            "get_recent_references_for_event", _get_recent_references_for_event_txn
+        )
+
+    @cached(tree=True)
+    def get_aggregation_groups_for_event(
+        self,
+        event_id,
+        event_type=None,
+        limit=5,
+        direction="b",
+        from_token=None,
+        to_token=None,
+    ):
+        """Get a list of annotations on the event, grouped by event type and
+        aggregation key, sorted by count.
+
+        This is used e.g. to get the what and how many reactions have happend
+        on an event.
+
+        Args:
+            event_id (str): Fetch events that relate to this event ID.
+            event_type (str|None): Only fetch events with this event type, if
+                given.
+            limit (int): Only fetch the `limit` groups.
+            direction (str): Whether to fetch the highest count first (`"b"`) or
+                the lowest count first (`"f"`).
+            from_token (AggregationPaginationToken|None): Fetch rows from the
+                given token, or from the start if None.
+            to_token (AggregationPaginationToken|None): Fetch rows up to the
+                given token, or up to the end if None.
+
+
+        Returns:
+            Deferred[PaginationChunk]: List of groups of annotations that
+            match. Each row is a dict with `type`, `key` and `count` fields.
+        """
+
+        where_clause = ["relates_to_id = ?", "relation_type = ?"]
+        where_args = [event_id, RelationTypes.ANNOTATION]
+
+        if event_type:
+            where_clause.append("type = ?")
+            where_args.append(event_type)
+
+        having_clause = generate_pagination_where_clause(
+            direction=direction,
+            column_names=("COUNT(*)", "MAX(stream_ordering)"),
+            from_token=attr.astuple(from_token) if from_token else None,
+            to_token=attr.astuple(to_token) if to_token else None,
+            engine=self.database_engine,
+        )
+
+        if direction == "b":
+            order = "DESC"
+        else:
+            order = "ASC"
+
+        if having_clause:
+            having_clause = "HAVING " + having_clause
+        else:
+            having_clause = ""
+
+        sql = """
+            SELECT type, aggregation_key, COUNT(DISTINCT sender), MAX(stream_ordering)
+            FROM event_relations
+            INNER JOIN events USING (event_id)
+            WHERE {where_clause}
+            GROUP BY relation_type, type, aggregation_key
+            {having_clause}
+            ORDER BY COUNT(*) {order}, MAX(stream_ordering) {order}
+            LIMIT ?
+        """.format(
+            where_clause=" AND ".join(where_clause),
+            order=order,
+            having_clause=having_clause,
+        )
+
+        def _get_aggregation_groups_for_event_txn(txn):
+            txn.execute(sql, where_args + [limit + 1])
+
+            next_batch = None
+            events = []
+            for row in txn:
+                events.append({"type": row[0], "key": row[1], "count": row[2]})
+                next_batch = AggregationPaginationToken(row[2], row[3])
+
+            if len(events) <= limit:
+                next_batch = None
+
+            return PaginationChunk(
+                chunk=list(events[:limit]), next_batch=next_batch, prev_batch=from_token
+            )
+
+        return self.db_pool.runInteraction(
+            "get_aggregation_groups_for_event", _get_aggregation_groups_for_event_txn
+        )
+
+    @cachedInlineCallbacks()
+    def get_applicable_edit(self, event_id):
+        """Get the most recent edit (if any) that has happened for the given
+        event.
+
+        Correctly handles checking whether edits were allowed to happen.
+
+        Args:
+            event_id (str): The original event ID
+
+        Returns:
+            Deferred[EventBase|None]: Returns the most recent edit, if any.
+        """
+
+        # We only allow edits for `m.room.message` events that have the same sender
+        # and event type. We can't assert these things during regular event auth so
+        # we have to do the checks post hoc.
+
+        # Fetches latest edit that has the same type and sender as the
+        # original, and is an `m.room.message`.
+        sql = """
+            SELECT edit.event_id FROM events AS edit
+            INNER JOIN event_relations USING (event_id)
+            INNER JOIN events AS original ON
+                original.event_id = relates_to_id
+                AND edit.type = original.type
+                AND edit.sender = original.sender
+            WHERE
+                relates_to_id = ?
+                AND relation_type = ?
+                AND edit.type = 'm.room.message'
+            ORDER by edit.origin_server_ts DESC, edit.event_id DESC
+            LIMIT 1
+        """
+
+        def _get_applicable_edit_txn(txn):
+            txn.execute(sql, (event_id, RelationTypes.REPLACE))
+            row = txn.fetchone()
+            if row:
+                return row[0]
+
+        edit_id = yield self.db_pool.runInteraction(
+            "get_applicable_edit", _get_applicable_edit_txn
+        )
+
+        if not edit_id:
+            return
+
+        edit_event = yield self.get_event(edit_id, allow_none=True)
+        return edit_event
+
+    def has_user_annotated_event(self, parent_id, event_type, aggregation_key, sender):
+        """Check if a user has already annotated an event with the same key
+        (e.g. already liked an event).
+
+        Args:
+            parent_id (str): The event being annotated
+            event_type (str): The event type of the annotation
+            aggregation_key (str): The aggregation key of the annotation
+            sender (str): The sender of the annotation
+
+        Returns:
+            Deferred[bool]
+        """
+
+        sql = """
+            SELECT 1 FROM event_relations
+            INNER JOIN events USING (event_id)
+            WHERE
+                relates_to_id = ?
+                AND relation_type = ?
+                AND type = ?
+                AND sender = ?
+                AND aggregation_key = ?
+            LIMIT 1;
+        """
+
+        def _get_if_user_has_annotated_event(txn):
+            txn.execute(
+                sql,
+                (
+                    parent_id,
+                    RelationTypes.ANNOTATION,
+                    event_type,
+                    sender,
+                    aggregation_key,
+                ),
+            )
+
+            return bool(txn.fetchone())
+
+        return self.db_pool.runInteraction(
+            "get_if_user_has_annotated_event", _get_if_user_has_annotated_event
+        )
+
+
+class RelationsStore(RelationsWorkerStore):
+    pass
diff --git a/synapse/storage/databases/main/room.py b/synapse/storage/databases/main/room.py
new file mode 100644
index 0000000000..f4008e6221
--- /dev/null
+++ b/synapse/storage/databases/main/room.py
@@ -0,0 +1,1429 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import collections
+import logging
+import re
+from abc import abstractmethod
+from enum import Enum
+from typing import Any, Dict, List, Optional, Tuple
+
+from canonicaljson import json
+
+from synapse.api.constants import EventTypes
+from synapse.api.errors import StoreError
+from synapse.api.room_versions import RoomVersion, RoomVersions
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.storage.database import DatabasePool, LoggingTransaction
+from synapse.storage.databases.main.search import SearchStore
+from synapse.types import ThirdPartyInstanceID
+from synapse.util.caches.descriptors import cached
+
+logger = logging.getLogger(__name__)
+
+
+OpsLevel = collections.namedtuple(
+    "OpsLevel", ("ban_level", "kick_level", "redact_level")
+)
+
+RatelimitOverride = collections.namedtuple(
+    "RatelimitOverride", ("messages_per_second", "burst_count")
+)
+
+
+class RoomSortOrder(Enum):
+    """
+    Enum to define the sorting method used when returning rooms with get_rooms_paginate
+
+    NAME = sort rooms alphabetically by name
+    JOINED_MEMBERS = sort rooms by membership size, highest to lowest
+    """
+
+    # ALPHABETICAL and SIZE are deprecated.
+    # ALPHABETICAL is the same as NAME.
+    ALPHABETICAL = "alphabetical"
+    # SIZE is the same as JOINED_MEMBERS.
+    SIZE = "size"
+    NAME = "name"
+    CANONICAL_ALIAS = "canonical_alias"
+    JOINED_MEMBERS = "joined_members"
+    JOINED_LOCAL_MEMBERS = "joined_local_members"
+    VERSION = "version"
+    CREATOR = "creator"
+    ENCRYPTION = "encryption"
+    FEDERATABLE = "federatable"
+    PUBLIC = "public"
+    JOIN_RULES = "join_rules"
+    GUEST_ACCESS = "guest_access"
+    HISTORY_VISIBILITY = "history_visibility"
+    STATE_EVENTS = "state_events"
+
+
+class RoomWorkerStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RoomWorkerStore, self).__init__(database, db_conn, hs)
+
+        self.config = hs.config
+
+    def get_room(self, room_id):
+        """Retrieve a room.
+
+        Args:
+            room_id (str): The ID of the room to retrieve.
+        Returns:
+            A dict containing the room information, or None if the room is unknown.
+        """
+        return self.db_pool.simple_select_one(
+            table="rooms",
+            keyvalues={"room_id": room_id},
+            retcols=("room_id", "is_public", "creator"),
+            desc="get_room",
+            allow_none=True,
+        )
+
+    def get_room_with_stats(self, room_id: str):
+        """Retrieve room with statistics.
+
+        Args:
+            room_id: The ID of the room to retrieve.
+        Returns:
+            A dict containing the room information, or None if the room is unknown.
+        """
+
+        def get_room_with_stats_txn(txn, room_id):
+            sql = """
+                SELECT room_id, state.name, state.canonical_alias, curr.joined_members,
+                  curr.local_users_in_room AS joined_local_members, rooms.room_version AS version,
+                  rooms.creator, state.encryption, state.is_federatable AS federatable,
+                  rooms.is_public AS public, state.join_rules, state.guest_access,
+                  state.history_visibility, curr.current_state_events AS state_events
+                FROM rooms
+                LEFT JOIN room_stats_state state USING (room_id)
+                LEFT JOIN room_stats_current curr USING (room_id)
+                WHERE room_id = ?
+                """
+            txn.execute(sql, [room_id])
+            # Catch error if sql returns empty result to return "None" instead of an error
+            try:
+                res = self.db_pool.cursor_to_dict(txn)[0]
+            except IndexError:
+                return None
+
+            res["federatable"] = bool(res["federatable"])
+            res["public"] = bool(res["public"])
+            return res
+
+        return self.db_pool.runInteraction(
+            "get_room_with_stats", get_room_with_stats_txn, room_id
+        )
+
+    def get_public_room_ids(self):
+        return self.db_pool.simple_select_onecol(
+            table="rooms",
+            keyvalues={"is_public": True},
+            retcol="room_id",
+            desc="get_public_room_ids",
+        )
+
+    def count_public_rooms(self, network_tuple, ignore_non_federatable):
+        """Counts the number of public rooms as tracked in the room_stats_current
+        and room_stats_state table.
+
+        Args:
+            network_tuple (ThirdPartyInstanceID|None)
+            ignore_non_federatable (bool): If true filters out non-federatable rooms
+        """
+
+        def _count_public_rooms_txn(txn):
+            query_args = []
+
+            if network_tuple:
+                if network_tuple.appservice_id:
+                    published_sql = """
+                        SELECT room_id from appservice_room_list
+                        WHERE appservice_id = ? AND network_id = ?
+                    """
+                    query_args.append(network_tuple.appservice_id)
+                    query_args.append(network_tuple.network_id)
+                else:
+                    published_sql = """
+                        SELECT room_id FROM rooms WHERE is_public
+                    """
+            else:
+                published_sql = """
+                    SELECT room_id FROM rooms WHERE is_public
+                    UNION SELECT room_id from appservice_room_list
+            """
+
+            sql = """
+                SELECT
+                    COALESCE(COUNT(*), 0)
+                FROM (
+                    %(published_sql)s
+                ) published
+                INNER JOIN room_stats_state USING (room_id)
+                INNER JOIN room_stats_current USING (room_id)
+                WHERE
+                    (
+                        join_rules = 'public' OR history_visibility = 'world_readable'
+                    )
+                    AND joined_members > 0
+            """ % {
+                "published_sql": published_sql
+            }
+
+            txn.execute(sql, query_args)
+            return txn.fetchone()[0]
+
+        return self.db_pool.runInteraction(
+            "count_public_rooms", _count_public_rooms_txn
+        )
+
+    async def get_largest_public_rooms(
+        self,
+        network_tuple: Optional[ThirdPartyInstanceID],
+        search_filter: Optional[dict],
+        limit: Optional[int],
+        bounds: Optional[Tuple[int, str]],
+        forwards: bool,
+        ignore_non_federatable: bool = False,
+    ):
+        """Gets the largest public rooms (where largest is in terms of joined
+        members, as tracked in the statistics table).
+
+        Args:
+            network_tuple
+            search_filter
+            limit: Maxmimum number of rows to return, unlimited otherwise.
+            bounds: An uppoer or lower bound to apply to result set if given,
+                consists of a joined member count and room_id (these are
+                excluded from result set).
+            forwards: true iff going forwards, going backwards otherwise
+            ignore_non_federatable: If true filters out non-federatable rooms.
+
+        Returns:
+            Rooms in order: biggest number of joined users first.
+            We then arbitrarily use the room_id as a tie breaker.
+
+        """
+
+        where_clauses = []
+        query_args = []
+
+        if network_tuple:
+            if network_tuple.appservice_id:
+                published_sql = """
+                    SELECT room_id from appservice_room_list
+                    WHERE appservice_id = ? AND network_id = ?
+                """
+                query_args.append(network_tuple.appservice_id)
+                query_args.append(network_tuple.network_id)
+            else:
+                published_sql = """
+                    SELECT room_id FROM rooms WHERE is_public
+                """
+        else:
+            published_sql = """
+                SELECT room_id FROM rooms WHERE is_public
+                UNION SELECT room_id from appservice_room_list
+            """
+
+        # Work out the bounds if we're given them, these bounds look slightly
+        # odd, but are designed to help query planner use indices by pulling
+        # out a common bound.
+        if bounds:
+            last_joined_members, last_room_id = bounds
+            if forwards:
+                where_clauses.append(
+                    """
+                        joined_members <= ? AND (
+                            joined_members < ? OR room_id < ?
+                        )
+                    """
+                )
+            else:
+                where_clauses.append(
+                    """
+                        joined_members >= ? AND (
+                            joined_members > ? OR room_id > ?
+                        )
+                    """
+                )
+
+            query_args += [last_joined_members, last_joined_members, last_room_id]
+
+        if ignore_non_federatable:
+            where_clauses.append("is_federatable")
+
+        if search_filter and search_filter.get("generic_search_term", None):
+            search_term = "%" + search_filter["generic_search_term"] + "%"
+
+            where_clauses.append(
+                """
+                    (
+                        LOWER(name) LIKE ?
+                        OR LOWER(topic) LIKE ?
+                        OR LOWER(canonical_alias) LIKE ?
+                    )
+                """
+            )
+            query_args += [
+                search_term.lower(),
+                search_term.lower(),
+                search_term.lower(),
+            ]
+
+        where_clause = ""
+        if where_clauses:
+            where_clause = " AND " + " AND ".join(where_clauses)
+
+        sql = """
+            SELECT
+                room_id, name, topic, canonical_alias, joined_members,
+                avatar, history_visibility, joined_members, guest_access
+            FROM (
+                %(published_sql)s
+            ) published
+            INNER JOIN room_stats_state USING (room_id)
+            INNER JOIN room_stats_current USING (room_id)
+            WHERE
+                (
+                    join_rules = 'public' OR history_visibility = 'world_readable'
+                )
+                AND joined_members > 0
+                %(where_clause)s
+            ORDER BY joined_members %(dir)s, room_id %(dir)s
+        """ % {
+            "published_sql": published_sql,
+            "where_clause": where_clause,
+            "dir": "DESC" if forwards else "ASC",
+        }
+
+        if limit is not None:
+            query_args.append(limit)
+
+            sql += """
+                LIMIT ?
+            """
+
+        def _get_largest_public_rooms_txn(txn):
+            txn.execute(sql, query_args)
+
+            results = self.db_pool.cursor_to_dict(txn)
+
+            if not forwards:
+                results.reverse()
+
+            return results
+
+        ret_val = await self.db_pool.runInteraction(
+            "get_largest_public_rooms", _get_largest_public_rooms_txn
+        )
+        return ret_val
+
+    @cached(max_entries=10000)
+    def is_room_blocked(self, room_id):
+        return self.db_pool.simple_select_one_onecol(
+            table="blocked_rooms",
+            keyvalues={"room_id": room_id},
+            retcol="1",
+            allow_none=True,
+            desc="is_room_blocked",
+        )
+
+    async def get_rooms_paginate(
+        self,
+        start: int,
+        limit: int,
+        order_by: RoomSortOrder,
+        reverse_order: bool,
+        search_term: Optional[str],
+    ) -> Tuple[List[Dict[str, Any]], int]:
+        """Function to retrieve a paginated list of rooms as json.
+
+        Args:
+            start: offset in the list
+            limit: maximum amount of rooms to retrieve
+            order_by: the sort order of the returned list
+            reverse_order: whether to reverse the room list
+            search_term: a string to filter room names by
+        Returns:
+            A list of room dicts and an integer representing the total number of
+            rooms that exist given this query
+        """
+        # Filter room names by a string
+        where_statement = ""
+        if search_term:
+            where_statement = "WHERE state.name LIKE ?"
+
+            # Our postgres db driver converts ? -> %s in SQL strings as that's the
+            # placeholder for postgres.
+            # HOWEVER, if you put a % into your SQL then everything goes wibbly.
+            # To get around this, we're going to surround search_term with %'s
+            # before giving it to the database in python instead
+            search_term = "%" + search_term + "%"
+
+        # Set ordering
+        if RoomSortOrder(order_by) == RoomSortOrder.SIZE:
+            # Deprecated in favour of RoomSortOrder.JOINED_MEMBERS
+            order_by_column = "curr.joined_members"
+            order_by_asc = False
+        elif RoomSortOrder(order_by) == RoomSortOrder.ALPHABETICAL:
+            # Deprecated in favour of RoomSortOrder.NAME
+            order_by_column = "state.name"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.NAME:
+            order_by_column = "state.name"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.CANONICAL_ALIAS:
+            order_by_column = "state.canonical_alias"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.JOINED_MEMBERS:
+            order_by_column = "curr.joined_members"
+            order_by_asc = False
+        elif RoomSortOrder(order_by) == RoomSortOrder.JOINED_LOCAL_MEMBERS:
+            order_by_column = "curr.local_users_in_room"
+            order_by_asc = False
+        elif RoomSortOrder(order_by) == RoomSortOrder.VERSION:
+            order_by_column = "rooms.room_version"
+            order_by_asc = False
+        elif RoomSortOrder(order_by) == RoomSortOrder.CREATOR:
+            order_by_column = "rooms.creator"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.ENCRYPTION:
+            order_by_column = "state.encryption"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.FEDERATABLE:
+            order_by_column = "state.is_federatable"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.PUBLIC:
+            order_by_column = "rooms.is_public"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.JOIN_RULES:
+            order_by_column = "state.join_rules"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.GUEST_ACCESS:
+            order_by_column = "state.guest_access"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.HISTORY_VISIBILITY:
+            order_by_column = "state.history_visibility"
+            order_by_asc = True
+        elif RoomSortOrder(order_by) == RoomSortOrder.STATE_EVENTS:
+            order_by_column = "curr.current_state_events"
+            order_by_asc = False
+        else:
+            raise StoreError(
+                500, "Incorrect value for order_by provided: %s" % order_by
+            )
+
+        # Whether to return the list in reverse order
+        if reverse_order:
+            # Flip the boolean
+            order_by_asc = not order_by_asc
+
+        # Create one query for getting the limited number of events that the user asked
+        # for, and another query for getting the total number of events that could be
+        # returned. Thus allowing us to see if there are more events to paginate through
+        info_sql = """
+            SELECT state.room_id, state.name, state.canonical_alias, curr.joined_members,
+              curr.local_users_in_room, rooms.room_version, rooms.creator,
+              state.encryption, state.is_federatable, rooms.is_public, state.join_rules,
+              state.guest_access, state.history_visibility, curr.current_state_events
+            FROM room_stats_state state
+            INNER JOIN room_stats_current curr USING (room_id)
+            INNER JOIN rooms USING (room_id)
+            %s
+            ORDER BY %s %s
+            LIMIT ?
+            OFFSET ?
+        """ % (
+            where_statement,
+            order_by_column,
+            "ASC" if order_by_asc else "DESC",
+        )
+
+        # Use a nested SELECT statement as SQL can't count(*) with an OFFSET
+        count_sql = """
+            SELECT count(*) FROM (
+              SELECT room_id FROM room_stats_state state
+              %s
+            ) AS get_room_ids
+        """ % (
+            where_statement,
+        )
+
+        def _get_rooms_paginate_txn(txn):
+            # Execute the data query
+            sql_values = (limit, start)
+            if search_term:
+                # Add the search term into the WHERE clause
+                sql_values = (search_term,) + sql_values
+            txn.execute(info_sql, sql_values)
+
+            # Refactor room query data into a structured dictionary
+            rooms = []
+            for room in txn:
+                rooms.append(
+                    {
+                        "room_id": room[0],
+                        "name": room[1],
+                        "canonical_alias": room[2],
+                        "joined_members": room[3],
+                        "joined_local_members": room[4],
+                        "version": room[5],
+                        "creator": room[6],
+                        "encryption": room[7],
+                        "federatable": room[8],
+                        "public": room[9],
+                        "join_rules": room[10],
+                        "guest_access": room[11],
+                        "history_visibility": room[12],
+                        "state_events": room[13],
+                    }
+                )
+
+            # Execute the count query
+
+            # Add the search term into the WHERE clause if present
+            sql_values = (search_term,) if search_term else ()
+            txn.execute(count_sql, sql_values)
+
+            room_count = txn.fetchone()
+            return rooms, room_count[0]
+
+        return await self.db_pool.runInteraction(
+            "get_rooms_paginate", _get_rooms_paginate_txn,
+        )
+
+    @cached(max_entries=10000)
+    async def get_ratelimit_for_user(self, user_id):
+        """Check if there are any overrides for ratelimiting for the given
+        user
+
+        Args:
+            user_id (str)
+
+        Returns:
+            RatelimitOverride if there is an override, else None. If the contents
+            of RatelimitOverride are None or 0 then ratelimitng has been
+            disabled for that user entirely.
+        """
+        row = await self.db_pool.simple_select_one(
+            table="ratelimit_override",
+            keyvalues={"user_id": user_id},
+            retcols=("messages_per_second", "burst_count"),
+            allow_none=True,
+            desc="get_ratelimit_for_user",
+        )
+
+        if row:
+            return RatelimitOverride(
+                messages_per_second=row["messages_per_second"],
+                burst_count=row["burst_count"],
+            )
+        else:
+            return None
+
+    @cached()
+    async def get_retention_policy_for_room(self, room_id):
+        """Get the retention policy for a given room.
+
+        If no retention policy has been found for this room, returns a policy defined
+        by the configured default policy (which has None as both the 'min_lifetime' and
+        the 'max_lifetime' if no default policy has been defined in the server's
+        configuration).
+
+        Args:
+            room_id (str): The ID of the room to get the retention policy of.
+
+        Returns:
+            dict[int, int]: "min_lifetime" and "max_lifetime" for this room.
+        """
+
+        def get_retention_policy_for_room_txn(txn):
+            txn.execute(
+                """
+                SELECT min_lifetime, max_lifetime FROM room_retention
+                INNER JOIN current_state_events USING (event_id, room_id)
+                WHERE room_id = ?;
+                """,
+                (room_id,),
+            )
+
+            return self.db_pool.cursor_to_dict(txn)
+
+        ret = await self.db_pool.runInteraction(
+            "get_retention_policy_for_room", get_retention_policy_for_room_txn,
+        )
+
+        # If we don't know this room ID, ret will be None, in this case return the default
+        # policy.
+        if not ret:
+            return {
+                "min_lifetime": self.config.retention_default_min_lifetime,
+                "max_lifetime": self.config.retention_default_max_lifetime,
+            }
+
+        row = ret[0]
+
+        # If one of the room's policy's attributes isn't defined, use the matching
+        # attribute from the default policy.
+        # The default values will be None if no default policy has been defined, or if one
+        # of the attributes is missing from the default policy.
+        if row["min_lifetime"] is None:
+            row["min_lifetime"] = self.config.retention_default_min_lifetime
+
+        if row["max_lifetime"] is None:
+            row["max_lifetime"] = self.config.retention_default_max_lifetime
+
+        return row
+
+    def get_media_mxcs_in_room(self, room_id):
+        """Retrieves all the local and remote media MXC URIs in a given room
+
+        Args:
+            room_id (str)
+
+        Returns:
+            The local and remote media as a lists of tuples where the key is
+            the hostname and the value is the media ID.
+        """
+
+        def _get_media_mxcs_in_room_txn(txn):
+            local_mxcs, remote_mxcs = self._get_media_mxcs_in_room_txn(txn, room_id)
+            local_media_mxcs = []
+            remote_media_mxcs = []
+
+            # Convert the IDs to MXC URIs
+            for media_id in local_mxcs:
+                local_media_mxcs.append("mxc://%s/%s" % (self.hs.hostname, media_id))
+            for hostname, media_id in remote_mxcs:
+                remote_media_mxcs.append("mxc://%s/%s" % (hostname, media_id))
+
+            return local_media_mxcs, remote_media_mxcs
+
+        return self.db_pool.runInteraction(
+            "get_media_ids_in_room", _get_media_mxcs_in_room_txn
+        )
+
+    def quarantine_media_ids_in_room(self, room_id, quarantined_by):
+        """For a room loops through all events with media and quarantines
+        the associated media
+        """
+
+        logger.info("Quarantining media in room: %s", room_id)
+
+        def _quarantine_media_in_room_txn(txn):
+            local_mxcs, remote_mxcs = self._get_media_mxcs_in_room_txn(txn, room_id)
+            return self._quarantine_media_txn(
+                txn, local_mxcs, remote_mxcs, quarantined_by
+            )
+
+        return self.db_pool.runInteraction(
+            "quarantine_media_in_room", _quarantine_media_in_room_txn
+        )
+
+    def _get_media_mxcs_in_room_txn(self, txn, room_id):
+        """Retrieves all the local and remote media MXC URIs in a given room
+
+        Args:
+            txn (cursor)
+            room_id (str)
+
+        Returns:
+            The local and remote media as a lists of tuples where the key is
+            the hostname and the value is the media ID.
+        """
+        mxc_re = re.compile("^mxc://([^/]+)/([^/#?]+)")
+
+        sql = """
+            SELECT stream_ordering, json FROM events
+            JOIN event_json USING (room_id, event_id)
+            WHERE room_id = ?
+                %(where_clause)s
+                AND contains_url = ? AND outlier = ?
+            ORDER BY stream_ordering DESC
+            LIMIT ?
+        """
+        txn.execute(sql % {"where_clause": ""}, (room_id, True, False, 100))
+
+        local_media_mxcs = []
+        remote_media_mxcs = []
+
+        while True:
+            next_token = None
+            for stream_ordering, content_json in txn:
+                next_token = stream_ordering
+                event_json = db_to_json(content_json)
+                content = event_json["content"]
+                content_url = content.get("url")
+                thumbnail_url = content.get("info", {}).get("thumbnail_url")
+
+                for url in (content_url, thumbnail_url):
+                    if not url:
+                        continue
+                    matches = mxc_re.match(url)
+                    if matches:
+                        hostname = matches.group(1)
+                        media_id = matches.group(2)
+                        if hostname == self.hs.hostname:
+                            local_media_mxcs.append(media_id)
+                        else:
+                            remote_media_mxcs.append((hostname, media_id))
+
+            if next_token is None:
+                # We've gone through the whole room, so we're finished.
+                break
+
+            txn.execute(
+                sql % {"where_clause": "AND stream_ordering < ?"},
+                (room_id, next_token, True, False, 100),
+            )
+
+        return local_media_mxcs, remote_media_mxcs
+
+    def quarantine_media_by_id(
+        self, server_name: str, media_id: str, quarantined_by: str,
+    ):
+        """quarantines a single local or remote media id
+
+        Args:
+            server_name: The name of the server that holds this media
+            media_id: The ID of the media to be quarantined
+            quarantined_by: The user ID that initiated the quarantine request
+        """
+        logger.info("Quarantining media: %s/%s", server_name, media_id)
+        is_local = server_name == self.config.server_name
+
+        def _quarantine_media_by_id_txn(txn):
+            local_mxcs = [media_id] if is_local else []
+            remote_mxcs = [(server_name, media_id)] if not is_local else []
+
+            return self._quarantine_media_txn(
+                txn, local_mxcs, remote_mxcs, quarantined_by
+            )
+
+        return self.db_pool.runInteraction(
+            "quarantine_media_by_user", _quarantine_media_by_id_txn
+        )
+
+    def quarantine_media_ids_by_user(self, user_id: str, quarantined_by: str):
+        """quarantines all local media associated with a single user
+
+        Args:
+            user_id: The ID of the user to quarantine media of
+            quarantined_by: The ID of the user who made the quarantine request
+        """
+
+        def _quarantine_media_by_user_txn(txn):
+            local_media_ids = self._get_media_ids_by_user_txn(txn, user_id)
+            return self._quarantine_media_txn(txn, local_media_ids, [], quarantined_by)
+
+        return self.db_pool.runInteraction(
+            "quarantine_media_by_user", _quarantine_media_by_user_txn
+        )
+
+    def _get_media_ids_by_user_txn(self, txn, user_id: str, filter_quarantined=True):
+        """Retrieves local media IDs by a given user
+
+        Args:
+            txn (cursor)
+            user_id: The ID of the user to retrieve media IDs of
+
+        Returns:
+            The local and remote media as a lists of tuples where the key is
+            the hostname and the value is the media ID.
+        """
+        # Local media
+        sql = """
+            SELECT media_id
+            FROM local_media_repository
+            WHERE user_id = ?
+            """
+        if filter_quarantined:
+            sql += "AND quarantined_by IS NULL"
+        txn.execute(sql, (user_id,))
+
+        local_media_ids = [row[0] for row in txn]
+
+        # TODO: Figure out all remote media a user has referenced in a message
+
+        return local_media_ids
+
+    def _quarantine_media_txn(
+        self,
+        txn,
+        local_mxcs: List[str],
+        remote_mxcs: List[Tuple[str, str]],
+        quarantined_by: str,
+    ) -> int:
+        """Quarantine local and remote media items
+
+        Args:
+            txn (cursor)
+            local_mxcs: A list of local mxc URLs
+            remote_mxcs: A list of (remote server, media id) tuples representing
+                remote mxc URLs
+            quarantined_by: The ID of the user who initiated the quarantine request
+        Returns:
+            The total number of media items quarantined
+        """
+        # Update all the tables to set the quarantined_by flag
+        txn.executemany(
+            """
+            UPDATE local_media_repository
+            SET quarantined_by = ?
+            WHERE media_id = ? AND safe_from_quarantine = ?
+        """,
+            ((quarantined_by, media_id, False) for media_id in local_mxcs),
+        )
+        # Note that a rowcount of -1 can be used to indicate no rows were affected.
+        total_media_quarantined = txn.rowcount if txn.rowcount > 0 else 0
+
+        txn.executemany(
+            """
+                UPDATE remote_media_cache
+                SET quarantined_by = ?
+                WHERE media_origin = ? AND media_id = ?
+            """,
+            ((quarantined_by, origin, media_id) for origin, media_id in remote_mxcs),
+        )
+        total_media_quarantined += txn.rowcount if txn.rowcount > 0 else 0
+
+        return total_media_quarantined
+
+    async def get_all_new_public_rooms(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for public rooms replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_new_public_rooms(txn):
+            sql = """
+                SELECT stream_id, room_id, visibility, appservice_id, network_id
+                FROM public_room_list_stream
+                WHERE stream_id > ? AND stream_id <= ?
+                ORDER BY stream_id ASC
+                LIMIT ?
+            """
+
+            txn.execute(sql, (last_id, current_id, limit))
+            updates = [(row[0], row[1:]) for row in txn]
+            limited = False
+            upto_token = current_id
+            if len(updates) >= limit:
+                upto_token = updates[-1][0]
+                limited = True
+
+            return updates, upto_token, limited
+
+        return await self.db_pool.runInteraction(
+            "get_all_new_public_rooms", get_all_new_public_rooms
+        )
+
+
+class RoomBackgroundUpdateStore(SQLBaseStore):
+    REMOVE_TOMESTONED_ROOMS_BG_UPDATE = "remove_tombstoned_rooms_from_directory"
+    ADD_ROOMS_ROOM_VERSION_COLUMN = "add_rooms_room_version_column"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RoomBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        self.config = hs.config
+
+        self.db_pool.updates.register_background_update_handler(
+            "insert_room_retention", self._background_insert_retention,
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            self.REMOVE_TOMESTONED_ROOMS_BG_UPDATE,
+            self._remove_tombstoned_rooms_from_directory,
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            self.ADD_ROOMS_ROOM_VERSION_COLUMN,
+            self._background_add_rooms_room_version_column,
+        )
+
+    async def _background_insert_retention(self, progress, batch_size):
+        """Retrieves a list of all rooms within a range and inserts an entry for each of
+        them into the room_retention table.
+        NULLs the property's columns if missing from the retention event in the room's
+        state (or NULLs all of them if there's no retention event in the room's state),
+        so that we fall back to the server's retention policy.
+        """
+
+        last_room = progress.get("room_id", "")
+
+        def _background_insert_retention_txn(txn):
+            txn.execute(
+                """
+                SELECT state.room_id, state.event_id, events.json
+                FROM current_state_events as state
+                LEFT JOIN event_json AS events ON (state.event_id = events.event_id)
+                WHERE state.room_id > ? AND state.type = '%s'
+                ORDER BY state.room_id ASC
+                LIMIT ?;
+                """
+                % EventTypes.Retention,
+                (last_room, batch_size),
+            )
+
+            rows = self.db_pool.cursor_to_dict(txn)
+
+            if not rows:
+                return True
+
+            for row in rows:
+                if not row["json"]:
+                    retention_policy = {}
+                else:
+                    ev = db_to_json(row["json"])
+                    retention_policy = ev["content"]
+
+                self.db_pool.simple_insert_txn(
+                    txn=txn,
+                    table="room_retention",
+                    values={
+                        "room_id": row["room_id"],
+                        "event_id": row["event_id"],
+                        "min_lifetime": retention_policy.get("min_lifetime"),
+                        "max_lifetime": retention_policy.get("max_lifetime"),
+                    },
+                )
+
+            logger.info("Inserted %d rows into room_retention", len(rows))
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, "insert_room_retention", {"room_id": rows[-1]["room_id"]}
+            )
+
+            if batch_size > len(rows):
+                return True
+            else:
+                return False
+
+        end = await self.db_pool.runInteraction(
+            "insert_room_retention", _background_insert_retention_txn,
+        )
+
+        if end:
+            await self.db_pool.updates._end_background_update("insert_room_retention")
+
+        return batch_size
+
+    async def _background_add_rooms_room_version_column(
+        self, progress: dict, batch_size: int
+    ):
+        """Background update to go and add room version inforamtion to `rooms`
+        table from `current_state_events` table.
+        """
+
+        last_room_id = progress.get("room_id", "")
+
+        def _background_add_rooms_room_version_column_txn(txn: LoggingTransaction):
+            sql = """
+                SELECT room_id, json FROM current_state_events
+                INNER JOIN event_json USING (room_id, event_id)
+                WHERE room_id > ? AND type = 'm.room.create' AND state_key = ''
+                ORDER BY room_id
+                LIMIT ?
+            """
+
+            txn.execute(sql, (last_room_id, batch_size))
+
+            updates = []
+            for room_id, event_json in txn:
+                event_dict = db_to_json(event_json)
+                room_version_id = event_dict.get("content", {}).get(
+                    "room_version", RoomVersions.V1.identifier
+                )
+
+                creator = event_dict.get("content").get("creator")
+
+                updates.append((room_id, creator, room_version_id))
+
+            if not updates:
+                return True
+
+            new_last_room_id = ""
+            for room_id, creator, room_version_id in updates:
+                # We upsert here just in case we don't already have a row,
+                # mainly for paranoia as much badness would happen if we don't
+                # insert the row and then try and get the room version for the
+                # room.
+                self.db_pool.simple_upsert_txn(
+                    txn,
+                    table="rooms",
+                    keyvalues={"room_id": room_id},
+                    values={"room_version": room_version_id},
+                    insertion_values={"is_public": False, "creator": creator},
+                )
+                new_last_room_id = room_id
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, self.ADD_ROOMS_ROOM_VERSION_COLUMN, {"room_id": new_last_room_id}
+            )
+
+            return False
+
+        end = await self.db_pool.runInteraction(
+            "_background_add_rooms_room_version_column",
+            _background_add_rooms_room_version_column_txn,
+        )
+
+        if end:
+            await self.db_pool.updates._end_background_update(
+                self.ADD_ROOMS_ROOM_VERSION_COLUMN
+            )
+
+        return batch_size
+
+    async def _remove_tombstoned_rooms_from_directory(
+        self, progress, batch_size
+    ) -> int:
+        """Removes any rooms with tombstone events from the room directory
+
+        Nowadays this is handled by the room upgrade handler, but we may have some
+        that got left behind
+        """
+
+        last_room = progress.get("room_id", "")
+
+        def _get_rooms(txn):
+            txn.execute(
+                """
+                SELECT room_id
+                FROM rooms r
+                INNER JOIN current_state_events cse USING (room_id)
+                WHERE room_id > ? AND r.is_public
+                AND cse.type = '%s' AND cse.state_key = ''
+                ORDER BY room_id ASC
+                LIMIT ?;
+                """
+                % EventTypes.Tombstone,
+                (last_room, batch_size),
+            )
+
+            return [row[0] for row in txn]
+
+        rooms = await self.db_pool.runInteraction(
+            "get_tombstoned_directory_rooms", _get_rooms
+        )
+
+        if not rooms:
+            await self.db_pool.updates._end_background_update(
+                self.REMOVE_TOMESTONED_ROOMS_BG_UPDATE
+            )
+            return 0
+
+        for room_id in rooms:
+            logger.info("Removing tombstoned room %s from the directory", room_id)
+            await self.set_room_is_public(room_id, False)
+
+        await self.db_pool.updates._background_update_progress(
+            self.REMOVE_TOMESTONED_ROOMS_BG_UPDATE, {"room_id": rooms[-1]}
+        )
+
+        return len(rooms)
+
+    @abstractmethod
+    def set_room_is_public(self, room_id, is_public):
+        # this will need to be implemented if a background update is performed with
+        # existing (tombstoned, public) rooms in the database.
+        #
+        # It's overridden by RoomStore for the synapse master.
+        raise NotImplementedError()
+
+
+class RoomStore(RoomBackgroundUpdateStore, RoomWorkerStore, SearchStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RoomStore, self).__init__(database, db_conn, hs)
+
+        self.config = hs.config
+
+    async def upsert_room_on_join(self, room_id: str, room_version: RoomVersion):
+        """Ensure that the room is stored in the table
+
+        Called when we join a room over federation, and overwrites any room version
+        currently in the table.
+        """
+        await self.db_pool.simple_upsert(
+            desc="upsert_room_on_join",
+            table="rooms",
+            keyvalues={"room_id": room_id},
+            values={"room_version": room_version.identifier},
+            insertion_values={"is_public": False, "creator": ""},
+            # rooms has a unique constraint on room_id, so no need to lock when doing an
+            # emulated upsert.
+            lock=False,
+        )
+
+    async def store_room(
+        self,
+        room_id: str,
+        room_creator_user_id: str,
+        is_public: bool,
+        room_version: RoomVersion,
+    ):
+        """Stores a room.
+
+        Args:
+            room_id: The desired room ID, can be None.
+            room_creator_user_id: The user ID of the room creator.
+            is_public: True to indicate that this room should appear in
+                public room lists.
+            room_version: The version of the room
+        Raises:
+            StoreError if the room could not be stored.
+        """
+        try:
+
+            def store_room_txn(txn, next_id):
+                self.db_pool.simple_insert_txn(
+                    txn,
+                    "rooms",
+                    {
+                        "room_id": room_id,
+                        "creator": room_creator_user_id,
+                        "is_public": is_public,
+                        "room_version": room_version.identifier,
+                    },
+                )
+                if is_public:
+                    self.db_pool.simple_insert_txn(
+                        txn,
+                        table="public_room_list_stream",
+                        values={
+                            "stream_id": next_id,
+                            "room_id": room_id,
+                            "visibility": is_public,
+                        },
+                    )
+
+            with self._public_room_id_gen.get_next() as next_id:
+                await self.db_pool.runInteraction(
+                    "store_room_txn", store_room_txn, next_id
+                )
+        except Exception as e:
+            logger.error("store_room with room_id=%s failed: %s", room_id, e)
+            raise StoreError(500, "Problem creating room.")
+
+    async def maybe_store_room_on_invite(self, room_id: str, room_version: RoomVersion):
+        """
+        When we receive an invite over federation, store the version of the room if we
+        don't already know the room version.
+        """
+        await self.db_pool.simple_upsert(
+            desc="maybe_store_room_on_invite",
+            table="rooms",
+            keyvalues={"room_id": room_id},
+            values={},
+            insertion_values={
+                "room_version": room_version.identifier,
+                "is_public": False,
+                "creator": "",
+            },
+            # rooms has a unique constraint on room_id, so no need to lock when doing an
+            # emulated upsert.
+            lock=False,
+        )
+
+    async def set_room_is_public(self, room_id, is_public):
+        def set_room_is_public_txn(txn, next_id):
+            self.db_pool.simple_update_one_txn(
+                txn,
+                table="rooms",
+                keyvalues={"room_id": room_id},
+                updatevalues={"is_public": is_public},
+            )
+
+            entries = self.db_pool.simple_select_list_txn(
+                txn,
+                table="public_room_list_stream",
+                keyvalues={
+                    "room_id": room_id,
+                    "appservice_id": None,
+                    "network_id": None,
+                },
+                retcols=("stream_id", "visibility"),
+            )
+
+            entries.sort(key=lambda r: r["stream_id"])
+
+            add_to_stream = True
+            if entries:
+                add_to_stream = bool(entries[-1]["visibility"]) != is_public
+
+            if add_to_stream:
+                self.db_pool.simple_insert_txn(
+                    txn,
+                    table="public_room_list_stream",
+                    values={
+                        "stream_id": next_id,
+                        "room_id": room_id,
+                        "visibility": is_public,
+                        "appservice_id": None,
+                        "network_id": None,
+                    },
+                )
+
+        with self._public_room_id_gen.get_next() as next_id:
+            await self.db_pool.runInteraction(
+                "set_room_is_public", set_room_is_public_txn, next_id
+            )
+        self.hs.get_notifier().on_new_replication_data()
+
+    async def set_room_is_public_appservice(
+        self, room_id, appservice_id, network_id, is_public
+    ):
+        """Edit the appservice/network specific public room list.
+
+        Each appservice can have a number of published room lists associated
+        with them, keyed off of an appservice defined `network_id`, which
+        basically represents a single instance of a bridge to a third party
+        network.
+
+        Args:
+            room_id (str)
+            appservice_id (str)
+            network_id (str)
+            is_public (bool): Whether to publish or unpublish the room from the
+                list.
+        """
+
+        def set_room_is_public_appservice_txn(txn, next_id):
+            if is_public:
+                try:
+                    self.db_pool.simple_insert_txn(
+                        txn,
+                        table="appservice_room_list",
+                        values={
+                            "appservice_id": appservice_id,
+                            "network_id": network_id,
+                            "room_id": room_id,
+                        },
+                    )
+                except self.database_engine.module.IntegrityError:
+                    # We've already inserted, nothing to do.
+                    return
+            else:
+                self.db_pool.simple_delete_txn(
+                    txn,
+                    table="appservice_room_list",
+                    keyvalues={
+                        "appservice_id": appservice_id,
+                        "network_id": network_id,
+                        "room_id": room_id,
+                    },
+                )
+
+            entries = self.db_pool.simple_select_list_txn(
+                txn,
+                table="public_room_list_stream",
+                keyvalues={
+                    "room_id": room_id,
+                    "appservice_id": appservice_id,
+                    "network_id": network_id,
+                },
+                retcols=("stream_id", "visibility"),
+            )
+
+            entries.sort(key=lambda r: r["stream_id"])
+
+            add_to_stream = True
+            if entries:
+                add_to_stream = bool(entries[-1]["visibility"]) != is_public
+
+            if add_to_stream:
+                self.db_pool.simple_insert_txn(
+                    txn,
+                    table="public_room_list_stream",
+                    values={
+                        "stream_id": next_id,
+                        "room_id": room_id,
+                        "visibility": is_public,
+                        "appservice_id": appservice_id,
+                        "network_id": network_id,
+                    },
+                )
+
+        with self._public_room_id_gen.get_next() as next_id:
+            await self.db_pool.runInteraction(
+                "set_room_is_public_appservice",
+                set_room_is_public_appservice_txn,
+                next_id,
+            )
+        self.hs.get_notifier().on_new_replication_data()
+
+    def get_room_count(self):
+        """Retrieve a list of all rooms
+        """
+
+        def f(txn):
+            sql = "SELECT count(*)  FROM rooms"
+            txn.execute(sql)
+            row = txn.fetchone()
+            return row[0] or 0
+
+        return self.db_pool.runInteraction("get_rooms", f)
+
+    def add_event_report(
+        self, room_id, event_id, user_id, reason, content, received_ts
+    ):
+        next_id = self._event_reports_id_gen.get_next()
+        return self.db_pool.simple_insert(
+            table="event_reports",
+            values={
+                "id": next_id,
+                "received_ts": received_ts,
+                "room_id": room_id,
+                "event_id": event_id,
+                "user_id": user_id,
+                "reason": reason,
+                "content": json.dumps(content),
+            },
+            desc="add_event_report",
+        )
+
+    def get_current_public_room_stream_id(self):
+        return self._public_room_id_gen.get_current_token()
+
+    async def block_room(self, room_id: str, user_id: str) -> None:
+        """Marks the room as blocked. Can be called multiple times.
+
+        Args:
+            room_id: Room to block
+            user_id: Who blocked it
+        """
+        await self.db_pool.simple_upsert(
+            table="blocked_rooms",
+            keyvalues={"room_id": room_id},
+            values={},
+            insertion_values={"user_id": user_id},
+            desc="block_room",
+        )
+        await self.db_pool.runInteraction(
+            "block_room_invalidation",
+            self._invalidate_cache_and_stream,
+            self.is_room_blocked,
+            (room_id,),
+        )
+
+    async def get_rooms_for_retention_period_in_range(
+        self, min_ms: Optional[int], max_ms: Optional[int], include_null: bool = False
+    ) -> Dict[str, dict]:
+        """Retrieves all of the rooms within the given retention range.
+
+        Optionally includes the rooms which don't have a retention policy.
+
+        Args:
+            min_ms: Duration in milliseconds that define the lower limit of
+                the range to handle (exclusive). If None, doesn't set a lower limit.
+            max_ms: Duration in milliseconds that define the upper limit of
+                the range to handle (inclusive). If None, doesn't set an upper limit.
+            include_null: Whether to include rooms which retention policy is NULL
+                in the returned set.
+
+        Returns:
+            The rooms within this range, along with their retention
+            policy. The key is "room_id", and maps to a dict describing the retention
+            policy associated with this room ID. The keys for this nested dict are
+            "min_lifetime" (int|None), and "max_lifetime" (int|None).
+        """
+
+        def get_rooms_for_retention_period_in_range_txn(txn):
+            range_conditions = []
+            args = []
+
+            if min_ms is not None:
+                range_conditions.append("max_lifetime > ?")
+                args.append(min_ms)
+
+            if max_ms is not None:
+                range_conditions.append("max_lifetime <= ?")
+                args.append(max_ms)
+
+            # Do a first query which will retrieve the rooms that have a retention policy
+            # in their current state.
+            sql = """
+                SELECT room_id, min_lifetime, max_lifetime FROM room_retention
+                INNER JOIN current_state_events USING (event_id, room_id)
+                """
+
+            if len(range_conditions):
+                sql += " WHERE (" + " AND ".join(range_conditions) + ")"
+
+                if include_null:
+                    sql += " OR max_lifetime IS NULL"
+
+            txn.execute(sql, args)
+
+            rows = self.db_pool.cursor_to_dict(txn)
+            rooms_dict = {}
+
+            for row in rows:
+                rooms_dict[row["room_id"]] = {
+                    "min_lifetime": row["min_lifetime"],
+                    "max_lifetime": row["max_lifetime"],
+                }
+
+            if include_null:
+                # If required, do a second query that retrieves all of the rooms we know
+                # of so we can handle rooms with no retention policy.
+                sql = "SELECT DISTINCT room_id FROM current_state_events"
+
+                txn.execute(sql)
+
+                rows = self.db_pool.cursor_to_dict(txn)
+
+                # If a room isn't already in the dict (i.e. it doesn't have a retention
+                # policy in its state), add it with a null policy.
+                for row in rows:
+                    if row["room_id"] not in rooms_dict:
+                        rooms_dict[row["room_id"]] = {
+                            "min_lifetime": None,
+                            "max_lifetime": None,
+                        }
+
+            return rooms_dict
+
+        rooms = await self.db_pool.runInteraction(
+            "get_rooms_for_retention_period_in_range",
+            get_rooms_for_retention_period_in_range_txn,
+        )
+
+        return rooms
diff --git a/synapse/storage/databases/main/roommember.py b/synapse/storage/databases/main/roommember.py
new file mode 100644
index 0000000000..7c5be251bd
--- /dev/null
+++ b/synapse/storage/databases/main/roommember.py
@@ -0,0 +1,1139 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from typing import Iterable, List, Set
+
+from twisted.internet import defer
+
+from synapse.api.constants import EventTypes, Membership
+from synapse.metrics import LaterGauge
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import (
+    LoggingTransaction,
+    SQLBaseStore,
+    db_to_json,
+    make_in_list_sql_clause,
+)
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.events_worker import EventsWorkerStore
+from synapse.storage.engines import Sqlite3Engine
+from synapse.storage.roommember import (
+    GetRoomsForUserWithStreamOrdering,
+    MemberSummary,
+    ProfileInfo,
+    RoomsForUser,
+)
+from synapse.types import Collection, get_domain_from_id
+from synapse.util.async_helpers import Linearizer
+from synapse.util.caches import intern_string
+from synapse.util.caches.descriptors import cached, cachedInlineCallbacks, cachedList
+from synapse.util.metrics import Measure
+
+logger = logging.getLogger(__name__)
+
+
+_MEMBERSHIP_PROFILE_UPDATE_NAME = "room_membership_profile_update"
+_CURRENT_STATE_MEMBERSHIP_UPDATE_NAME = "current_state_events_membership"
+
+
+class RoomMemberWorkerStore(EventsWorkerStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RoomMemberWorkerStore, self).__init__(database, db_conn, hs)
+
+        # Is the current_state_events.membership up to date? Or is the
+        # background update still running?
+        self._current_state_events_membership_up_to_date = False
+
+        txn = LoggingTransaction(
+            db_conn.cursor(),
+            name="_check_safe_current_state_events_membership_updated",
+            database_engine=self.database_engine,
+        )
+        self._check_safe_current_state_events_membership_updated_txn(txn)
+        txn.close()
+
+        if self.hs.config.metrics_flags.known_servers:
+            self._known_servers_count = 1
+            self.hs.get_clock().looping_call(
+                run_as_background_process,
+                60 * 1000,
+                "_count_known_servers",
+                self._count_known_servers,
+            )
+            self.hs.get_clock().call_later(
+                1000,
+                run_as_background_process,
+                "_count_known_servers",
+                self._count_known_servers,
+            )
+            LaterGauge(
+                "synapse_federation_known_servers",
+                "",
+                [],
+                lambda: self._known_servers_count,
+            )
+
+    @defer.inlineCallbacks
+    def _count_known_servers(self):
+        """
+        Count the servers that this server knows about.
+
+        The statistic is stored on the class for the
+        `synapse_federation_known_servers` LaterGauge to collect.
+        """
+
+        def _transact(txn):
+            if isinstance(self.database_engine, Sqlite3Engine):
+                query = """
+                    SELECT COUNT(DISTINCT substr(out.user_id, pos+1))
+                    FROM (
+                        SELECT rm.user_id as user_id, instr(rm.user_id, ':')
+                            AS pos FROM room_memberships as rm
+                        INNER JOIN current_state_events as c ON rm.event_id = c.event_id
+                        WHERE c.type = 'm.room.member'
+                    ) as out
+                """
+            else:
+                query = """
+                    SELECT COUNT(DISTINCT split_part(state_key, ':', 2))
+                    FROM current_state_events
+                    WHERE type = 'm.room.member' AND membership = 'join';
+                """
+            txn.execute(query)
+            return list(txn)[0][0]
+
+        count = yield self.db_pool.runInteraction("get_known_servers", _transact)
+
+        # We always know about ourselves, even if we have nothing in
+        # room_memberships (for example, the server is new).
+        self._known_servers_count = max([count, 1])
+        return self._known_servers_count
+
+    def _check_safe_current_state_events_membership_updated_txn(self, txn):
+        """Checks if it is safe to assume the new current_state_events
+        membership column is up to date
+        """
+
+        pending_update = self.db_pool.simple_select_one_txn(
+            txn,
+            table="background_updates",
+            keyvalues={"update_name": _CURRENT_STATE_MEMBERSHIP_UPDATE_NAME},
+            retcols=["update_name"],
+            allow_none=True,
+        )
+
+        self._current_state_events_membership_up_to_date = not pending_update
+
+        # If the update is still running, reschedule to run.
+        if pending_update:
+            self._clock.call_later(
+                15.0,
+                run_as_background_process,
+                "_check_safe_current_state_events_membership_updated",
+                self.db_pool.runInteraction,
+                "_check_safe_current_state_events_membership_updated",
+                self._check_safe_current_state_events_membership_updated_txn,
+            )
+
+    @cached(max_entries=100000, iterable=True)
+    def get_users_in_room(self, room_id):
+        return self.db_pool.runInteraction(
+            "get_users_in_room", self.get_users_in_room_txn, room_id
+        )
+
+    def get_users_in_room_txn(self, txn, room_id):
+        # If we can assume current_state_events.membership is up to date
+        # then we can avoid a join, which is a Very Good Thing given how
+        # frequently this function gets called.
+        if self._current_state_events_membership_up_to_date:
+            sql = """
+                SELECT state_key FROM current_state_events
+                WHERE type = 'm.room.member' AND room_id = ? AND membership = ?
+            """
+        else:
+            sql = """
+                SELECT state_key FROM room_memberships as m
+                INNER JOIN current_state_events as c
+                ON m.event_id = c.event_id
+                AND m.room_id = c.room_id
+                AND m.user_id = c.state_key
+                WHERE c.type = 'm.room.member' AND c.room_id = ? AND m.membership = ?
+            """
+
+        txn.execute(sql, (room_id, Membership.JOIN))
+        return [r[0] for r in txn]
+
+    @cached(max_entries=100000)
+    def get_room_summary(self, room_id):
+        """ Get the details of a room roughly suitable for use by the room
+        summary extension to /sync. Useful when lazy loading room members.
+        Args:
+            room_id (str): The room ID to query
+        Returns:
+            Deferred[dict[str, MemberSummary]:
+                dict of membership states, pointing to a MemberSummary named tuple.
+        """
+
+        def _get_room_summary_txn(txn):
+            # first get counts.
+            # We do this all in one transaction to keep the cache small.
+            # FIXME: get rid of this when we have room_stats
+
+            # If we can assume current_state_events.membership is up to date
+            # then we can avoid a join, which is a Very Good Thing given how
+            # frequently this function gets called.
+            if self._current_state_events_membership_up_to_date:
+                # Note, rejected events will have a null membership field, so
+                # we we manually filter them out.
+                sql = """
+                    SELECT count(*), membership FROM current_state_events
+                    WHERE type = 'm.room.member' AND room_id = ?
+                        AND membership IS NOT NULL
+                    GROUP BY membership
+                """
+            else:
+                sql = """
+                    SELECT count(*), m.membership FROM room_memberships as m
+                    INNER JOIN current_state_events as c
+                    ON m.event_id = c.event_id
+                    AND m.room_id = c.room_id
+                    AND m.user_id = c.state_key
+                    WHERE c.type = 'm.room.member' AND c.room_id = ?
+                    GROUP BY m.membership
+                """
+
+            txn.execute(sql, (room_id,))
+            res = {}
+            for count, membership in txn:
+                summary = res.setdefault(membership, MemberSummary([], count))
+
+            # we order by membership and then fairly arbitrarily by event_id so
+            # heroes are consistent
+            if self._current_state_events_membership_up_to_date:
+                # Note, rejected events will have a null membership field, so
+                # we we manually filter them out.
+                sql = """
+                    SELECT state_key, membership, event_id
+                    FROM current_state_events
+                    WHERE type = 'm.room.member' AND room_id = ?
+                        AND membership IS NOT NULL
+                    ORDER BY
+                        CASE membership WHEN ? THEN 1 WHEN ? THEN 2 ELSE 3 END ASC,
+                        event_id ASC
+                    LIMIT ?
+                """
+            else:
+                sql = """
+                    SELECT c.state_key, m.membership, c.event_id
+                    FROM room_memberships as m
+                    INNER JOIN current_state_events as c USING (room_id, event_id)
+                    WHERE c.type = 'm.room.member' AND c.room_id = ?
+                    ORDER BY
+                        CASE m.membership WHEN ? THEN 1 WHEN ? THEN 2 ELSE 3 END ASC,
+                        c.event_id ASC
+                    LIMIT ?
+                """
+
+            # 6 is 5 (number of heroes) plus 1, in case one of them is the calling user.
+            txn.execute(sql, (room_id, Membership.JOIN, Membership.INVITE, 6))
+            for user_id, membership, event_id in txn:
+                summary = res[membership]
+                # we will always have a summary for this membership type at this
+                # point given the summary currently contains the counts.
+                members = summary.members
+                members.append((user_id, event_id))
+
+            return res
+
+        return self.db_pool.runInteraction("get_room_summary", _get_room_summary_txn)
+
+    def _get_user_counts_in_room_txn(self, txn, room_id):
+        """
+        Get the user count in a room by membership.
+
+        Args:
+            room_id (str)
+            membership (Membership)
+
+        Returns:
+            Deferred[int]
+        """
+        sql = """
+        SELECT m.membership, count(*) FROM room_memberships as m
+            INNER JOIN current_state_events as c USING(event_id)
+            WHERE c.type = 'm.room.member' AND c.room_id = ?
+            GROUP BY m.membership
+        """
+
+        txn.execute(sql, (room_id,))
+        return {row[0]: row[1] for row in txn}
+
+    @cached()
+    def get_invited_rooms_for_local_user(self, user_id):
+        """ Get all the rooms the *local* user is invited to
+
+        Args:
+            user_id (str): The user ID.
+        Returns:
+            A deferred list of RoomsForUser.
+        """
+
+        return self.get_rooms_for_local_user_where_membership_is(
+            user_id, [Membership.INVITE]
+        )
+
+    @defer.inlineCallbacks
+    def get_invite_for_local_user_in_room(self, user_id, room_id):
+        """Gets the invite for the given *local* user and room
+
+        Args:
+            user_id (str)
+            room_id (str)
+
+        Returns:
+            Deferred: Resolves to either a RoomsForUser or None if no invite was
+                found.
+        """
+        invites = yield self.get_invited_rooms_for_local_user(user_id)
+        for invite in invites:
+            if invite.room_id == room_id:
+                return invite
+        return None
+
+    @defer.inlineCallbacks
+    def get_rooms_for_local_user_where_membership_is(self, user_id, membership_list):
+        """ Get all the rooms for this *local* user where the membership for this user
+        matches one in the membership list.
+
+        Filters out forgotten rooms.
+
+        Args:
+            user_id (str): The user ID.
+            membership_list (list): A list of synapse.api.constants.Membership
+            values which the user must be in.
+
+        Returns:
+            Deferred[list[RoomsForUser]]
+        """
+        if not membership_list:
+            return defer.succeed(None)
+
+        rooms = yield self.db_pool.runInteraction(
+            "get_rooms_for_local_user_where_membership_is",
+            self._get_rooms_for_local_user_where_membership_is_txn,
+            user_id,
+            membership_list,
+        )
+
+        # Now we filter out forgotten rooms
+        forgotten_rooms = yield self.get_forgotten_rooms_for_user(user_id)
+        return [room for room in rooms if room.room_id not in forgotten_rooms]
+
+    def _get_rooms_for_local_user_where_membership_is_txn(
+        self, txn, user_id, membership_list
+    ):
+        # Paranoia check.
+        if not self.hs.is_mine_id(user_id):
+            raise Exception(
+                "Cannot call 'get_rooms_for_local_user_where_membership_is' on non-local user %r"
+                % (user_id,),
+            )
+
+        clause, args = make_in_list_sql_clause(
+            self.database_engine, "c.membership", membership_list
+        )
+
+        sql = """
+            SELECT room_id, e.sender, c.membership, event_id, e.stream_ordering
+            FROM local_current_membership AS c
+            INNER JOIN events AS e USING (room_id, event_id)
+            WHERE
+                user_id = ?
+                AND %s
+        """ % (
+            clause,
+        )
+
+        txn.execute(sql, (user_id, *args))
+        results = [RoomsForUser(**r) for r in self.db_pool.cursor_to_dict(txn)]
+
+        return results
+
+    @cached(max_entries=500000, iterable=True)
+    def get_rooms_for_user_with_stream_ordering(self, user_id):
+        """Returns a set of room_ids the user is currently joined to.
+
+        If a remote user only returns rooms this server is currently
+        participating in.
+
+        Args:
+            user_id (str)
+
+        Returns:
+            Deferred[frozenset[GetRoomsForUserWithStreamOrdering]]: Returns
+            the rooms the user is in currently, along with the stream ordering
+            of the most recent join for that user and room.
+        """
+        return self.db_pool.runInteraction(
+            "get_rooms_for_user_with_stream_ordering",
+            self._get_rooms_for_user_with_stream_ordering_txn,
+            user_id,
+        )
+
+    def _get_rooms_for_user_with_stream_ordering_txn(self, txn, user_id):
+        # We use `current_state_events` here and not `local_current_membership`
+        # as a) this gets called with remote users and b) this only gets called
+        # for rooms the server is participating in.
+        if self._current_state_events_membership_up_to_date:
+            sql = """
+                SELECT room_id, e.stream_ordering
+                FROM current_state_events AS c
+                INNER JOIN events AS e USING (room_id, event_id)
+                WHERE
+                    c.type = 'm.room.member'
+                    AND state_key = ?
+                    AND c.membership = ?
+            """
+        else:
+            sql = """
+                SELECT room_id, e.stream_ordering
+                FROM current_state_events AS c
+                INNER JOIN room_memberships AS m USING (room_id, event_id)
+                INNER JOIN events AS e USING (room_id, event_id)
+                WHERE
+                    c.type = 'm.room.member'
+                    AND state_key = ?
+                    AND m.membership = ?
+            """
+
+        txn.execute(sql, (user_id, Membership.JOIN))
+        results = frozenset(GetRoomsForUserWithStreamOrdering(*row) for row in txn)
+
+        return results
+
+    async def get_users_server_still_shares_room_with(
+        self, user_ids: Collection[str]
+    ) -> Set[str]:
+        """Given a list of users return the set that the server still share a
+        room with.
+        """
+
+        if not user_ids:
+            return set()
+
+        def _get_users_server_still_shares_room_with_txn(txn):
+            sql = """
+                SELECT state_key FROM current_state_events
+                WHERE
+                    type = 'm.room.member'
+                    AND membership = 'join'
+                    AND %s
+                GROUP BY state_key
+            """
+
+            clause, args = make_in_list_sql_clause(
+                self.database_engine, "state_key", user_ids
+            )
+
+            txn.execute(sql % (clause,), args)
+
+            return {row[0] for row in txn}
+
+        return await self.db_pool.runInteraction(
+            "get_users_server_still_shares_room_with",
+            _get_users_server_still_shares_room_with_txn,
+        )
+
+    @defer.inlineCallbacks
+    def get_rooms_for_user(self, user_id, on_invalidate=None):
+        """Returns a set of room_ids the user is currently joined to.
+
+        If a remote user only returns rooms this server is currently
+        participating in.
+        """
+        rooms = yield self.get_rooms_for_user_with_stream_ordering(
+            user_id, on_invalidate=on_invalidate
+        )
+        return frozenset(r.room_id for r in rooms)
+
+    @cachedInlineCallbacks(max_entries=500000, cache_context=True, iterable=True)
+    def get_users_who_share_room_with_user(self, user_id, cache_context):
+        """Returns the set of users who share a room with `user_id`
+        """
+        room_ids = yield self.get_rooms_for_user(
+            user_id, on_invalidate=cache_context.invalidate
+        )
+
+        user_who_share_room = set()
+        for room_id in room_ids:
+            user_ids = yield self.get_users_in_room(
+                room_id, on_invalidate=cache_context.invalidate
+            )
+            user_who_share_room.update(user_ids)
+
+        return user_who_share_room
+
+    @defer.inlineCallbacks
+    def get_joined_users_from_context(self, event, context):
+        state_group = context.state_group
+        if not state_group:
+            # If state_group is None it means it has yet to be assigned a
+            # state group, i.e. we need to make sure that calls with a state_group
+            # of None don't hit previous cached calls with a None state_group.
+            # To do this we set the state_group to a new object as object() != object()
+            state_group = object()
+
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
+        result = yield self._get_joined_users_from_context(
+            event.room_id, state_group, current_state_ids, event=event, context=context
+        )
+        return result
+
+    @defer.inlineCallbacks
+    def get_joined_users_from_state(self, room_id, state_entry):
+        state_group = state_entry.state_group
+        if not state_group:
+            # If state_group is None it means it has yet to be assigned a
+            # state group, i.e. we need to make sure that calls with a state_group
+            # of None don't hit previous cached calls with a None state_group.
+            # To do this we set the state_group to a new object as object() != object()
+            state_group = object()
+
+        with Measure(self._clock, "get_joined_users_from_state"):
+            return (
+                yield self._get_joined_users_from_context(
+                    room_id, state_group, state_entry.state, context=state_entry
+                )
+            )
+
+    @cachedInlineCallbacks(
+        num_args=2, cache_context=True, iterable=True, max_entries=100000
+    )
+    def _get_joined_users_from_context(
+        self,
+        room_id,
+        state_group,
+        current_state_ids,
+        cache_context,
+        event=None,
+        context=None,
+    ):
+        # We don't use `state_group`, it's there so that we can cache based
+        # on it. However, it's important that it's never None, since two current_states
+        # with a state_group of None are likely to be different.
+        # See bulk_get_push_rules_for_room for how we work around this.
+        assert state_group is not None
+
+        users_in_room = {}
+        member_event_ids = [
+            e_id
+            for key, e_id in current_state_ids.items()
+            if key[0] == EventTypes.Member
+        ]
+
+        if context is not None:
+            # If we have a context with a delta from a previous state group,
+            # check if we also have the result from the previous group in cache.
+            # If we do then we can reuse that result and simply update it with
+            # any membership changes in `delta_ids`
+            if context.prev_group and context.delta_ids:
+                prev_res = self._get_joined_users_from_context.cache.get(
+                    (room_id, context.prev_group), None
+                )
+                if prev_res and isinstance(prev_res, dict):
+                    users_in_room = dict(prev_res)
+                    member_event_ids = [
+                        e_id
+                        for key, e_id in context.delta_ids.items()
+                        if key[0] == EventTypes.Member
+                    ]
+                    for etype, state_key in context.delta_ids:
+                        if etype == EventTypes.Member:
+                            users_in_room.pop(state_key, None)
+
+        # We check if we have any of the member event ids in the event cache
+        # before we ask the DB
+
+        # We don't update the event cache hit ratio as it completely throws off
+        # the hit ratio counts. After all, we don't populate the cache if we
+        # miss it here
+        event_map = self._get_events_from_cache(
+            member_event_ids, allow_rejected=False, update_metrics=False
+        )
+
+        missing_member_event_ids = []
+        for event_id in member_event_ids:
+            ev_entry = event_map.get(event_id)
+            if ev_entry:
+                if ev_entry.event.membership == Membership.JOIN:
+                    users_in_room[ev_entry.event.state_key] = ProfileInfo(
+                        display_name=ev_entry.event.content.get("displayname", None),
+                        avatar_url=ev_entry.event.content.get("avatar_url", None),
+                    )
+            else:
+                missing_member_event_ids.append(event_id)
+
+        if missing_member_event_ids:
+            event_to_memberships = yield self._get_joined_profiles_from_event_ids(
+                missing_member_event_ids
+            )
+            users_in_room.update((row for row in event_to_memberships.values() if row))
+
+        if event is not None and event.type == EventTypes.Member:
+            if event.membership == Membership.JOIN:
+                if event.event_id in member_event_ids:
+                    users_in_room[event.state_key] = ProfileInfo(
+                        display_name=event.content.get("displayname", None),
+                        avatar_url=event.content.get("avatar_url", None),
+                    )
+
+        return users_in_room
+
+    @cached(max_entries=10000)
+    def _get_joined_profile_from_event_id(self, event_id):
+        raise NotImplementedError()
+
+    @cachedList(
+        cached_method_name="_get_joined_profile_from_event_id",
+        list_name="event_ids",
+        inlineCallbacks=True,
+    )
+    def _get_joined_profiles_from_event_ids(self, event_ids):
+        """For given set of member event_ids check if they point to a join
+        event and if so return the associated user and profile info.
+
+        Args:
+            event_ids (Iterable[str]): The member event IDs to lookup
+
+        Returns:
+            Deferred[dict[str, Tuple[str, ProfileInfo]|None]]: Map from event ID
+            to `user_id` and ProfileInfo (or None if not join event).
+        """
+
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="room_memberships",
+            column="event_id",
+            iterable=event_ids,
+            retcols=("user_id", "display_name", "avatar_url", "event_id"),
+            keyvalues={"membership": Membership.JOIN},
+            batch_size=500,
+            desc="_get_membership_from_event_ids",
+        )
+
+        return {
+            row["event_id"]: (
+                row["user_id"],
+                ProfileInfo(
+                    avatar_url=row["avatar_url"], display_name=row["display_name"]
+                ),
+            )
+            for row in rows
+        }
+
+    @cachedInlineCallbacks(max_entries=10000)
+    def is_host_joined(self, room_id, host):
+        if "%" in host or "_" in host:
+            raise Exception("Invalid host name")
+
+        sql = """
+            SELECT state_key FROM current_state_events AS c
+            INNER JOIN room_memberships AS m USING (event_id)
+            WHERE m.membership = 'join'
+                AND type = 'm.room.member'
+                AND c.room_id = ?
+                AND state_key LIKE ?
+            LIMIT 1
+        """
+
+        # We do need to be careful to ensure that host doesn't have any wild cards
+        # in it, but we checked above for known ones and we'll check below that
+        # the returned user actually has the correct domain.
+        like_clause = "%:" + host
+
+        rows = yield self.db_pool.execute(
+            "is_host_joined", None, sql, room_id, like_clause
+        )
+
+        if not rows:
+            return False
+
+        user_id = rows[0][0]
+        if get_domain_from_id(user_id) != host:
+            # This can only happen if the host name has something funky in it
+            raise Exception("Invalid host name")
+
+        return True
+
+    @cachedInlineCallbacks()
+    def was_host_joined(self, room_id, host):
+        """Check whether the server is or ever was in the room.
+
+        Args:
+            room_id (str)
+            host (str)
+
+        Returns:
+            Deferred: Resolves to True if the host is/was in the room, otherwise
+            False.
+        """
+        if "%" in host or "_" in host:
+            raise Exception("Invalid host name")
+
+        sql = """
+            SELECT user_id FROM room_memberships
+            WHERE room_id = ?
+                AND user_id LIKE ?
+                AND membership = 'join'
+            LIMIT 1
+        """
+
+        # We do need to be careful to ensure that host doesn't have any wild cards
+        # in it, but we checked above for known ones and we'll check below that
+        # the returned user actually has the correct domain.
+        like_clause = "%:" + host
+
+        rows = yield self.db_pool.execute(
+            "was_host_joined", None, sql, room_id, like_clause
+        )
+
+        if not rows:
+            return False
+
+        user_id = rows[0][0]
+        if get_domain_from_id(user_id) != host:
+            # This can only happen if the host name has something funky in it
+            raise Exception("Invalid host name")
+
+        return True
+
+    @defer.inlineCallbacks
+    def get_joined_hosts(self, room_id, state_entry):
+        state_group = state_entry.state_group
+        if not state_group:
+            # If state_group is None it means it has yet to be assigned a
+            # state group, i.e. we need to make sure that calls with a state_group
+            # of None don't hit previous cached calls with a None state_group.
+            # To do this we set the state_group to a new object as object() != object()
+            state_group = object()
+
+        with Measure(self._clock, "get_joined_hosts"):
+            return (
+                yield self._get_joined_hosts(
+                    room_id, state_group, state_entry.state, state_entry=state_entry
+                )
+            )
+
+    @cachedInlineCallbacks(num_args=2, max_entries=10000, iterable=True)
+    # @defer.inlineCallbacks
+    def _get_joined_hosts(self, room_id, state_group, current_state_ids, state_entry):
+        # We don't use `state_group`, its there so that we can cache based
+        # on it. However, its important that its never None, since two current_state's
+        # with a state_group of None are likely to be different.
+        # See bulk_get_push_rules_for_room for how we work around this.
+        assert state_group is not None
+
+        cache = yield self._get_joined_hosts_cache(room_id)
+        joined_hosts = yield cache.get_destinations(state_entry)
+
+        return joined_hosts
+
+    @cached(max_entries=10000)
+    def _get_joined_hosts_cache(self, room_id):
+        return _JoinedHostsCache(self, room_id)
+
+    @cachedInlineCallbacks(num_args=2)
+    def did_forget(self, user_id, room_id):
+        """Returns whether user_id has elected to discard history for room_id.
+
+        Returns False if they have since re-joined."""
+
+        def f(txn):
+            sql = (
+                "SELECT"
+                "  COUNT(*)"
+                " FROM"
+                "  room_memberships"
+                " WHERE"
+                "  user_id = ?"
+                " AND"
+                "  room_id = ?"
+                " AND"
+                "  forgotten = 0"
+            )
+            txn.execute(sql, (user_id, room_id))
+            rows = txn.fetchall()
+            return rows[0][0]
+
+        count = yield self.db_pool.runInteraction("did_forget_membership", f)
+        return count == 0
+
+    @cached()
+    def get_forgotten_rooms_for_user(self, user_id):
+        """Gets all rooms the user has forgotten.
+
+        Args:
+            user_id (str)
+
+        Returns:
+            Deferred[set[str]]
+        """
+
+        def _get_forgotten_rooms_for_user_txn(txn):
+            # This is a slightly convoluted query that first looks up all rooms
+            # that the user has forgotten in the past, then rechecks that list
+            # to see if any have subsequently been updated. This is done so that
+            # we can use a partial index on `forgotten = 1` on the assumption
+            # that few users will actually forget many rooms.
+            #
+            # Note that a room is considered "forgotten" if *all* membership
+            # events for that user and room have the forgotten field set (as
+            # when a user forgets a room we update all rows for that user and
+            # room, not just the current one).
+            sql = """
+                SELECT room_id, (
+                    SELECT count(*) FROM room_memberships
+                    WHERE room_id = m.room_id AND user_id = m.user_id AND forgotten = 0
+                ) AS count
+                FROM room_memberships AS m
+                WHERE user_id = ? AND forgotten = 1
+                GROUP BY room_id, user_id;
+            """
+            txn.execute(sql, (user_id,))
+            return {row[0] for row in txn if row[1] == 0}
+
+        return self.db_pool.runInteraction(
+            "get_forgotten_rooms_for_user", _get_forgotten_rooms_for_user_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_rooms_user_has_been_in(self, user_id):
+        """Get all rooms that the user has ever been in.
+
+        Args:
+            user_id (str)
+
+        Returns:
+            Deferred[set[str]]: Set of room IDs.
+        """
+
+        room_ids = yield self.db_pool.simple_select_onecol(
+            table="room_memberships",
+            keyvalues={"membership": Membership.JOIN, "user_id": user_id},
+            retcol="room_id",
+            desc="get_rooms_user_has_been_in",
+        )
+
+        return set(room_ids)
+
+    def get_membership_from_event_ids(
+        self, member_event_ids: Iterable[str]
+    ) -> List[dict]:
+        """Get user_id and membership of a set of event IDs.
+        """
+
+        return self.db_pool.simple_select_many_batch(
+            table="room_memberships",
+            column="event_id",
+            iterable=member_event_ids,
+            retcols=("user_id", "membership", "event_id"),
+            keyvalues={},
+            batch_size=500,
+            desc="get_membership_from_event_ids",
+        )
+
+    async def is_local_host_in_room_ignoring_users(
+        self, room_id: str, ignore_users: Collection[str]
+    ) -> bool:
+        """Check if there are any local users, excluding those in the given
+        list, in the room.
+        """
+
+        clause, args = make_in_list_sql_clause(
+            self.database_engine, "user_id", ignore_users
+        )
+
+        sql = """
+            SELECT 1 FROM local_current_membership
+            WHERE
+                room_id = ? AND membership = ?
+                AND NOT (%s)
+                LIMIT 1
+        """ % (
+            clause,
+        )
+
+        def _is_local_host_in_room_ignoring_users_txn(txn):
+            txn.execute(sql, (room_id, Membership.JOIN, *args))
+
+            return bool(txn.fetchone())
+
+        return await self.db_pool.runInteraction(
+            "is_local_host_in_room_ignoring_users",
+            _is_local_host_in_room_ignoring_users_txn,
+        )
+
+
+class RoomMemberBackgroundUpdateStore(SQLBaseStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RoomMemberBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+        self.db_pool.updates.register_background_update_handler(
+            _MEMBERSHIP_PROFILE_UPDATE_NAME, self._background_add_membership_profile
+        )
+        self.db_pool.updates.register_background_update_handler(
+            _CURRENT_STATE_MEMBERSHIP_UPDATE_NAME,
+            self._background_current_state_membership,
+        )
+        self.db_pool.updates.register_background_index_update(
+            "room_membership_forgotten_idx",
+            index_name="room_memberships_user_room_forgotten",
+            table="room_memberships",
+            columns=["user_id", "room_id"],
+            where_clause="forgotten = 1",
+        )
+
+    @defer.inlineCallbacks
+    def _background_add_membership_profile(self, progress, batch_size):
+        target_min_stream_id = progress.get(
+            "target_min_stream_id_inclusive", self._min_stream_order_on_start
+        )
+        max_stream_id = progress.get(
+            "max_stream_id_exclusive", self._stream_order_on_start + 1
+        )
+
+        INSERT_CLUMP_SIZE = 1000
+
+        def add_membership_profile_txn(txn):
+            sql = """
+                SELECT stream_ordering, event_id, events.room_id, event_json.json
+                FROM events
+                INNER JOIN event_json USING (event_id)
+                INNER JOIN room_memberships USING (event_id)
+                WHERE ? <= stream_ordering AND stream_ordering < ?
+                AND type = 'm.room.member'
+                ORDER BY stream_ordering DESC
+                LIMIT ?
+            """
+
+            txn.execute(sql, (target_min_stream_id, max_stream_id, batch_size))
+
+            rows = self.db_pool.cursor_to_dict(txn)
+            if not rows:
+                return 0
+
+            min_stream_id = rows[-1]["stream_ordering"]
+
+            to_update = []
+            for row in rows:
+                event_id = row["event_id"]
+                room_id = row["room_id"]
+                try:
+                    event_json = db_to_json(row["json"])
+                    content = event_json["content"]
+                except Exception:
+                    continue
+
+                display_name = content.get("displayname", None)
+                avatar_url = content.get("avatar_url", None)
+
+                if display_name or avatar_url:
+                    to_update.append((display_name, avatar_url, event_id, room_id))
+
+            to_update_sql = """
+                UPDATE room_memberships SET display_name = ?, avatar_url = ?
+                WHERE event_id = ? AND room_id = ?
+            """
+            for index in range(0, len(to_update), INSERT_CLUMP_SIZE):
+                clump = to_update[index : index + INSERT_CLUMP_SIZE]
+                txn.executemany(to_update_sql, clump)
+
+            progress = {
+                "target_min_stream_id_inclusive": target_min_stream_id,
+                "max_stream_id_exclusive": min_stream_id,
+            }
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, _MEMBERSHIP_PROFILE_UPDATE_NAME, progress
+            )
+
+            return len(rows)
+
+        result = yield self.db_pool.runInteraction(
+            _MEMBERSHIP_PROFILE_UPDATE_NAME, add_membership_profile_txn
+        )
+
+        if not result:
+            yield self.db_pool.updates._end_background_update(
+                _MEMBERSHIP_PROFILE_UPDATE_NAME
+            )
+
+        return result
+
+    @defer.inlineCallbacks
+    def _background_current_state_membership(self, progress, batch_size):
+        """Update the new membership column on current_state_events.
+
+        This works by iterating over all rooms in alphebetical order.
+        """
+
+        def _background_current_state_membership_txn(txn, last_processed_room):
+            processed = 0
+            while processed < batch_size:
+                txn.execute(
+                    """
+                        SELECT MIN(room_id) FROM current_state_events WHERE room_id > ?
+                    """,
+                    (last_processed_room,),
+                )
+                row = txn.fetchone()
+                if not row or not row[0]:
+                    return processed, True
+
+                (next_room,) = row
+
+                sql = """
+                    UPDATE current_state_events
+                    SET membership = (
+                        SELECT membership FROM room_memberships
+                        WHERE event_id = current_state_events.event_id
+                    )
+                    WHERE room_id = ?
+                """
+                txn.execute(sql, (next_room,))
+                processed += txn.rowcount
+
+                last_processed_room = next_room
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn,
+                _CURRENT_STATE_MEMBERSHIP_UPDATE_NAME,
+                {"last_processed_room": last_processed_room},
+            )
+
+            return processed, False
+
+        # If we haven't got a last processed room then just use the empty
+        # string, which will compare before all room IDs correctly.
+        last_processed_room = progress.get("last_processed_room", "")
+
+        row_count, finished = yield self.db_pool.runInteraction(
+            "_background_current_state_membership_update",
+            _background_current_state_membership_txn,
+            last_processed_room,
+        )
+
+        if finished:
+            yield self.db_pool.updates._end_background_update(
+                _CURRENT_STATE_MEMBERSHIP_UPDATE_NAME
+            )
+
+        return row_count
+
+
+class RoomMemberStore(RoomMemberWorkerStore, RoomMemberBackgroundUpdateStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(RoomMemberStore, self).__init__(database, db_conn, hs)
+
+    def forget(self, user_id, room_id):
+        """Indicate that user_id wishes to discard history for room_id."""
+
+        def f(txn):
+            sql = (
+                "UPDATE"
+                "  room_memberships"
+                " SET"
+                "  forgotten = 1"
+                " WHERE"
+                "  user_id = ?"
+                " AND"
+                "  room_id = ?"
+            )
+            txn.execute(sql, (user_id, room_id))
+
+            self._invalidate_cache_and_stream(txn, self.did_forget, (user_id, room_id))
+            self._invalidate_cache_and_stream(
+                txn, self.get_forgotten_rooms_for_user, (user_id,)
+            )
+
+        return self.db_pool.runInteraction("forget_membership", f)
+
+
+class _JoinedHostsCache(object):
+    """Cache for joined hosts in a room that is optimised to handle updates
+    via state deltas.
+    """
+
+    def __init__(self, store, room_id):
+        self.store = store
+        self.room_id = room_id
+
+        self.hosts_to_joined_users = {}
+
+        self.state_group = object()
+
+        self.linearizer = Linearizer("_JoinedHostsCache")
+
+        self._len = 0
+
+    @defer.inlineCallbacks
+    def get_destinations(self, state_entry):
+        """Get set of destinations for a state entry
+
+        Args:
+            state_entry(synapse.state._StateCacheEntry)
+        """
+        if state_entry.state_group == self.state_group:
+            return frozenset(self.hosts_to_joined_users)
+
+        with (yield self.linearizer.queue(())):
+            if state_entry.state_group == self.state_group:
+                pass
+            elif state_entry.prev_group == self.state_group:
+                for (typ, state_key), event_id in state_entry.delta_ids.items():
+                    if typ != EventTypes.Member:
+                        continue
+
+                    host = intern_string(get_domain_from_id(state_key))
+                    user_id = state_key
+                    known_joins = self.hosts_to_joined_users.setdefault(host, set())
+
+                    event = yield self.store.get_event(event_id)
+                    if event.membership == Membership.JOIN:
+                        known_joins.add(user_id)
+                    else:
+                        known_joins.discard(user_id)
+
+                        if not known_joins:
+                            self.hosts_to_joined_users.pop(host, None)
+            else:
+                joined_users = yield self.store.get_joined_users_from_state(
+                    self.room_id, state_entry
+                )
+
+                self.hosts_to_joined_users = {}
+                for user_id in joined_users:
+                    host = intern_string(get_domain_from_id(user_id))
+                    self.hosts_to_joined_users.setdefault(host, set()).add(user_id)
+
+            if state_entry.state_group:
+                self.state_group = state_entry.state_group
+            else:
+                self.state_group = object()
+            self._len = sum(len(v) for v in self.hosts_to_joined_users.values())
+        return frozenset(self.hosts_to_joined_users)
+
+    def __len__(self):
+        return self._len
diff --git a/synapse/storage/databases/main/schema/delta/12/v12.sql b/synapse/storage/databases/main/schema/delta/12/v12.sql
new file mode 100644
index 0000000000..5964c5aaac
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/12/v12.sql
@@ -0,0 +1,63 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS rejections(
+    event_id TEXT NOT NULL,
+    reason TEXT NOT NULL,
+    last_check TEXT NOT NULL,
+    UNIQUE (event_id)
+);
+
+-- Push notification endpoints that users have configured
+CREATE TABLE IF NOT EXISTS pushers (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  user_name TEXT NOT NULL,
+  profile_tag VARCHAR(32) NOT NULL,
+  kind VARCHAR(8) NOT NULL,
+  app_id VARCHAR(64) NOT NULL,
+  app_display_name VARCHAR(64) NOT NULL,
+  device_display_name VARCHAR(128) NOT NULL,
+  pushkey VARBINARY(512) NOT NULL,
+  ts BIGINT UNSIGNED NOT NULL,
+  lang VARCHAR(8),
+  data LONGBLOB,
+  last_token TEXT,
+  last_success BIGINT UNSIGNED,
+  failing_since BIGINT UNSIGNED,
+  UNIQUE (app_id, pushkey)
+);
+
+CREATE TABLE IF NOT EXISTS push_rules (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  user_name TEXT NOT NULL,
+  rule_id TEXT NOT NULL,
+  priority_class TINYINT NOT NULL,
+  priority INTEGER NOT NULL DEFAULT 0,
+  conditions TEXT NOT NULL,
+  actions TEXT NOT NULL,
+  UNIQUE(user_name, rule_id)
+);
+
+CREATE INDEX IF NOT EXISTS push_rules_user_name on push_rules (user_name);
+
+CREATE TABLE IF NOT EXISTS user_filters(
+  user_id TEXT,
+  filter_id BIGINT UNSIGNED,
+  filter_json LONGBLOB
+);
+
+CREATE INDEX IF NOT EXISTS user_filters_by_user_id_filter_id ON user_filters(
+    user_id, filter_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/13/v13.sql b/synapse/storage/databases/main/schema/delta/13/v13.sql
new file mode 100644
index 0000000000..f8649e5d99
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/13/v13.sql
@@ -0,0 +1,19 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* We used to create a tables called application_services and
+ * application_services_regex, but these are no longer used and are removed in
+ * delta 54.
+ */
diff --git a/synapse/storage/databases/main/schema/delta/14/v14.sql b/synapse/storage/databases/main/schema/delta/14/v14.sql
new file mode 100644
index 0000000000..a831920da6
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/14/v14.sql
@@ -0,0 +1,23 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+CREATE TABLE IF NOT EXISTS push_rules_enable (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  user_name TEXT NOT NULL,
+  rule_id TEXT NOT NULL,
+  enabled TINYINT,
+  UNIQUE(user_name, rule_id)
+);
+
+CREATE INDEX IF NOT EXISTS push_rules_enable_user_name on push_rules_enable (user_name);
diff --git a/synapse/storage/databases/main/schema/delta/15/appservice_txns.sql b/synapse/storage/databases/main/schema/delta/15/appservice_txns.sql
new file mode 100644
index 0000000000..e4f5e76aec
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/15/appservice_txns.sql
@@ -0,0 +1,31 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS application_services_state(
+    as_id TEXT PRIMARY KEY,
+    state VARCHAR(5),
+    last_txn INTEGER
+);
+
+CREATE TABLE IF NOT EXISTS application_services_txns(
+    as_id TEXT NOT NULL,
+    txn_id INTEGER NOT NULL,
+    event_ids TEXT NOT NULL,
+    UNIQUE(as_id, txn_id)
+);
+
+CREATE INDEX IF NOT EXISTS application_services_txns_id ON application_services_txns (
+    as_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/15/presence_indices.sql b/synapse/storage/databases/main/schema/delta/15/presence_indices.sql
new file mode 100644
index 0000000000..6b8d0f1ca7
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/15/presence_indices.sql
@@ -0,0 +1,2 @@
+
+CREATE INDEX IF NOT EXISTS presence_list_user_id ON presence_list (user_id);
diff --git a/synapse/storage/databases/main/schema/delta/15/v15.sql b/synapse/storage/databases/main/schema/delta/15/v15.sql
new file mode 100644
index 0000000000..9523d2bcc3
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/15/v15.sql
@@ -0,0 +1,24 @@
+-- Drop, copy & recreate pushers table to change unique key
+-- Also add access_token column at the same time
+CREATE TABLE IF NOT EXISTS pushers2 (
+  id BIGINT PRIMARY KEY,
+  user_name TEXT NOT NULL,
+  access_token BIGINT DEFAULT NULL,
+  profile_tag VARCHAR(32) NOT NULL,
+  kind VARCHAR(8) NOT NULL,
+  app_id VARCHAR(64) NOT NULL,
+  app_display_name VARCHAR(64) NOT NULL,
+  device_display_name VARCHAR(128) NOT NULL,
+  pushkey bytea NOT NULL,
+  ts BIGINT NOT NULL,
+  lang VARCHAR(8),
+  data bytea,
+  last_token TEXT,
+  last_success BIGINT,
+  failing_since BIGINT,
+  UNIQUE (app_id, pushkey)
+);
+INSERT INTO pushers2 (id, user_name, profile_tag, kind, app_id, app_display_name, device_display_name, pushkey, ts, lang, data, last_token, last_success, failing_since)
+  SELECT id, user_name, profile_tag, kind, app_id, app_display_name, device_display_name, pushkey, ts, lang, data, last_token, last_success, failing_since FROM pushers;
+DROP TABLE pushers;
+ALTER TABLE pushers2 RENAME TO pushers;
diff --git a/synapse/storage/databases/main/schema/delta/16/events_order_index.sql b/synapse/storage/databases/main/schema/delta/16/events_order_index.sql
new file mode 100644
index 0000000000..a48f215170
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/16/events_order_index.sql
@@ -0,0 +1,4 @@
+CREATE INDEX events_order ON events (topological_ordering, stream_ordering);
+CREATE INDEX events_order_room ON events (
+    room_id, topological_ordering, stream_ordering
+);
diff --git a/synapse/storage/databases/main/schema/delta/16/remote_media_cache_index.sql b/synapse/storage/databases/main/schema/delta/16/remote_media_cache_index.sql
new file mode 100644
index 0000000000..7a15265cb1
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/16/remote_media_cache_index.sql
@@ -0,0 +1,2 @@
+CREATE INDEX IF NOT EXISTS remote_media_cache_thumbnails_media_id
+    ON remote_media_cache_thumbnails (media_id);
\ No newline at end of file
diff --git a/synapse/storage/databases/main/schema/delta/16/remove_duplicates.sql b/synapse/storage/databases/main/schema/delta/16/remove_duplicates.sql
new file mode 100644
index 0000000000..65c97b5e2f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/16/remove_duplicates.sql
@@ -0,0 +1,9 @@
+
+
+DELETE FROM event_to_state_groups WHERE state_group not in (
+    SELECT MAX(state_group) FROM event_to_state_groups GROUP BY event_id
+);
+
+DELETE FROM event_to_state_groups WHERE rowid not in (
+    SELECT MIN(rowid) FROM event_to_state_groups GROUP BY event_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/16/room_alias_index.sql b/synapse/storage/databases/main/schema/delta/16/room_alias_index.sql
new file mode 100644
index 0000000000..f82486132b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/16/room_alias_index.sql
@@ -0,0 +1,3 @@
+
+CREATE INDEX IF NOT EXISTS room_aliases_id ON room_aliases(room_id);
+CREATE INDEX IF NOT EXISTS room_alias_servers_alias ON room_alias_servers(room_alias);
diff --git a/synapse/storage/databases/main/schema/delta/16/unique_constraints.sql b/synapse/storage/databases/main/schema/delta/16/unique_constraints.sql
new file mode 100644
index 0000000000..5b8de52c33
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/16/unique_constraints.sql
@@ -0,0 +1,72 @@
+
+-- We can use SQLite features here, since other db support was only added in v16
+
+--
+DELETE FROM current_state_events WHERE rowid not in (
+    SELECT MIN(rowid) FROM current_state_events GROUP BY event_id
+);
+
+DROP INDEX IF EXISTS current_state_events_event_id;
+CREATE UNIQUE INDEX current_state_events_event_id ON current_state_events(event_id);
+
+--
+DELETE FROM room_memberships WHERE rowid not in (
+    SELECT MIN(rowid) FROM room_memberships GROUP BY event_id
+);
+
+DROP INDEX IF EXISTS room_memberships_event_id;
+CREATE UNIQUE INDEX room_memberships_event_id ON room_memberships(event_id);
+
+--
+DELETE FROM topics WHERE rowid not in (
+    SELECT MIN(rowid) FROM topics GROUP BY event_id
+);
+
+DROP INDEX IF EXISTS topics_event_id;
+CREATE UNIQUE INDEX topics_event_id ON topics(event_id);
+
+--
+DELETE FROM room_names WHERE rowid not in (
+    SELECT MIN(rowid) FROM room_names GROUP BY event_id
+);
+
+DROP INDEX IF EXISTS room_names_id;
+CREATE UNIQUE INDEX room_names_id ON room_names(event_id);
+
+--
+DELETE FROM presence WHERE rowid not in (
+    SELECT MIN(rowid) FROM presence GROUP BY user_id
+);
+
+DROP INDEX IF EXISTS presence_id;
+CREATE UNIQUE INDEX presence_id ON presence(user_id);
+
+--
+DELETE FROM presence_allow_inbound WHERE rowid not in (
+    SELECT MIN(rowid) FROM presence_allow_inbound
+    GROUP BY observed_user_id, observer_user_id
+);
+
+DROP INDEX IF EXISTS presence_allow_inbound_observers;
+CREATE UNIQUE INDEX presence_allow_inbound_observers ON presence_allow_inbound(
+    observed_user_id, observer_user_id
+);
+
+--
+DELETE FROM presence_list WHERE rowid not in (
+    SELECT MIN(rowid) FROM presence_list
+    GROUP BY user_id, observed_user_id
+);
+
+DROP INDEX IF EXISTS presence_list_observers;
+CREATE UNIQUE INDEX presence_list_observers ON presence_list(
+    user_id, observed_user_id
+);
+
+--
+DELETE FROM room_aliases WHERE rowid not in (
+    SELECT MIN(rowid) FROM room_aliases GROUP BY room_alias
+);
+
+DROP INDEX IF EXISTS room_aliases_id;
+CREATE INDEX room_aliases_id ON room_aliases(room_id);
diff --git a/synapse/storage/databases/main/schema/delta/16/users.sql b/synapse/storage/databases/main/schema/delta/16/users.sql
new file mode 100644
index 0000000000..cd0709250d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/16/users.sql
@@ -0,0 +1,56 @@
+-- Convert `access_tokens`.user from rowids to user strings.
+-- MUST BE DONE BEFORE REMOVING ID COLUMN FROM USERS TABLE BELOW
+CREATE TABLE IF NOT EXISTS new_access_tokens(
+    id BIGINT UNSIGNED PRIMARY KEY,
+    user_id TEXT NOT NULL,
+    device_id TEXT,
+    token TEXT NOT NULL,
+    last_used BIGINT UNSIGNED,
+    UNIQUE(token)
+);
+
+INSERT INTO new_access_tokens
+    SELECT a.id, u.name, a.device_id, a.token, a.last_used
+    FROM access_tokens as a
+    INNER JOIN users as u ON u.id = a.user_id;
+
+DROP TABLE access_tokens;
+
+ALTER TABLE new_access_tokens RENAME TO access_tokens;
+
+-- Remove ID column from `users` table
+CREATE TABLE IF NOT EXISTS new_users(
+    name TEXT,
+    password_hash TEXT,
+    creation_ts BIGINT UNSIGNED,
+    admin BOOL DEFAULT 0 NOT NULL,
+    UNIQUE(name)
+);
+
+INSERT INTO new_users SELECT name, password_hash, creation_ts, admin FROM users;
+
+DROP TABLE users;
+
+ALTER TABLE new_users RENAME TO users;
+
+
+-- Remove UNIQUE constraint from `user_ips` table
+CREATE TABLE IF NOT EXISTS new_user_ips (
+    user_id TEXT NOT NULL,
+    access_token TEXT NOT NULL,
+    device_id TEXT,
+    ip TEXT NOT NULL,
+    user_agent TEXT NOT NULL,
+    last_seen BIGINT UNSIGNED NOT NULL
+);
+
+INSERT INTO new_user_ips
+    SELECT user, access_token, device_id, ip, user_agent, last_seen FROM user_ips;
+
+DROP TABLE user_ips;
+
+ALTER TABLE new_user_ips RENAME TO user_ips;
+
+CREATE INDEX IF NOT EXISTS user_ips_user ON user_ips(user_id);
+CREATE INDEX IF NOT EXISTS user_ips_user_ip ON user_ips(user_id, access_token, ip);
+
diff --git a/synapse/storage/databases/main/schema/delta/17/drop_indexes.sql b/synapse/storage/databases/main/schema/delta/17/drop_indexes.sql
new file mode 100644
index 0000000000..7c9a90e27f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/17/drop_indexes.sql
@@ -0,0 +1,18 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+DROP INDEX IF EXISTS sent_transaction_dest;
+DROP INDEX IF EXISTS sent_transaction_sent;
+DROP INDEX IF EXISTS user_ips_user;
diff --git a/synapse/storage/databases/main/schema/delta/17/server_keys.sql b/synapse/storage/databases/main/schema/delta/17/server_keys.sql
new file mode 100644
index 0000000000..70b247a06b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/17/server_keys.sql
@@ -0,0 +1,24 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS server_keys_json (
+    server_name TEXT, -- Server name.
+    key_id TEXT, -- Requested key id.
+    from_server TEXT, -- Which server the keys were fetched from.
+    ts_added_ms INTEGER, -- When the keys were fetched
+    ts_valid_until_ms INTEGER, -- When this version of the keys exipires.
+    key_json bytea, -- JSON certificate for the remote server.
+    CONSTRAINT uniqueness UNIQUE (server_name, key_id, from_server)
+);
diff --git a/synapse/storage/databases/main/schema/delta/17/user_threepids.sql b/synapse/storage/databases/main/schema/delta/17/user_threepids.sql
new file mode 100644
index 0000000000..c17715ac80
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/17/user_threepids.sql
@@ -0,0 +1,9 @@
+CREATE TABLE user_threepids (
+    user_id TEXT NOT NULL,
+    medium TEXT NOT NULL,
+    address TEXT NOT NULL,
+    validated_at BIGINT NOT NULL,
+    added_at BIGINT NOT NULL,
+    CONSTRAINT user_medium_address UNIQUE (user_id, medium, address)
+);
+CREATE INDEX user_threepids_user_id ON user_threepids(user_id);
diff --git a/synapse/storage/databases/main/schema/delta/18/server_keys_bigger_ints.sql b/synapse/storage/databases/main/schema/delta/18/server_keys_bigger_ints.sql
new file mode 100644
index 0000000000..6e0871c92b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/18/server_keys_bigger_ints.sql
@@ -0,0 +1,32 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE IF NOT EXISTS new_server_keys_json (
+    server_name TEXT NOT NULL, -- Server name.
+    key_id TEXT NOT NULL, -- Requested key id.
+    from_server TEXT NOT NULL, -- Which server the keys were fetched from.
+    ts_added_ms BIGINT NOT NULL, -- When the keys were fetched
+    ts_valid_until_ms BIGINT NOT NULL, -- When this version of the keys exipires.
+    key_json bytea NOT NULL, -- JSON certificate for the remote server.
+    CONSTRAINT server_keys_json_uniqueness UNIQUE (server_name, key_id, from_server)
+);
+
+INSERT INTO new_server_keys_json
+    SELECT server_name, key_id, from_server,ts_added_ms, ts_valid_until_ms, key_json FROM server_keys_json ;
+
+DROP TABLE server_keys_json;
+
+ALTER TABLE new_server_keys_json RENAME TO server_keys_json;
diff --git a/synapse/storage/databases/main/schema/delta/19/event_index.sql b/synapse/storage/databases/main/schema/delta/19/event_index.sql
new file mode 100644
index 0000000000..18b97b4332
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/19/event_index.sql
@@ -0,0 +1,19 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE INDEX events_order_topo_stream_room ON events(
+    topological_ordering, stream_ordering, room_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/20/dummy.sql b/synapse/storage/databases/main/schema/delta/20/dummy.sql
new file mode 100644
index 0000000000..e0ac49d1ec
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/20/dummy.sql
@@ -0,0 +1 @@
+SELECT 1;
diff --git a/synapse/storage/databases/main/schema/delta/20/pushers.py b/synapse/storage/databases/main/schema/delta/20/pushers.py
new file mode 100644
index 0000000000..3edfcfd783
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/20/pushers.py
@@ -0,0 +1,88 @@
+# Copyright 2015, 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+"""
+Main purpose of this upgrade is to change the unique key on the
+pushers table again (it was missed when the v16 full schema was
+made) but this also changes the pushkey and data columns to text.
+When selecting a bytea column into a text column, postgres inserts
+the hex encoded data, and there's no portable way of getting the
+UTF-8 bytes, so we have to do it in Python.
+"""
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    logger.info("Porting pushers table...")
+    cur.execute(
+        """
+        CREATE TABLE IF NOT EXISTS pushers2 (
+          id BIGINT PRIMARY KEY,
+          user_name TEXT NOT NULL,
+          access_token BIGINT DEFAULT NULL,
+          profile_tag VARCHAR(32) NOT NULL,
+          kind VARCHAR(8) NOT NULL,
+          app_id VARCHAR(64) NOT NULL,
+          app_display_name VARCHAR(64) NOT NULL,
+          device_display_name VARCHAR(128) NOT NULL,
+          pushkey TEXT NOT NULL,
+          ts BIGINT NOT NULL,
+          lang VARCHAR(8),
+          data TEXT,
+          last_token TEXT,
+          last_success BIGINT,
+          failing_since BIGINT,
+          UNIQUE (app_id, pushkey, user_name)
+        )
+    """
+    )
+    cur.execute(
+        """SELECT
+        id, user_name, access_token, profile_tag, kind,
+        app_id, app_display_name, device_display_name,
+        pushkey, ts, lang, data, last_token, last_success,
+        failing_since
+        FROM pushers
+    """
+    )
+    count = 0
+    for row in cur.fetchall():
+        row = list(row)
+        row[8] = bytes(row[8]).decode("utf-8")
+        row[11] = bytes(row[11]).decode("utf-8")
+        cur.execute(
+            database_engine.convert_param_style(
+                """
+            INSERT into pushers2 (
+            id, user_name, access_token, profile_tag, kind,
+            app_id, app_display_name, device_display_name,
+            pushkey, ts, lang, data, last_token, last_success,
+            failing_since
+            ) values (%s)"""
+                % (",".join(["?" for _ in range(len(row))]))
+            ),
+            row,
+        )
+        count += 1
+    cur.execute("DROP TABLE pushers")
+    cur.execute("ALTER TABLE pushers2 RENAME TO pushers")
+    logger.info("Moved %d pushers to new table", count)
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/21/end_to_end_keys.sql b/synapse/storage/databases/main/schema/delta/21/end_to_end_keys.sql
new file mode 100644
index 0000000000..4c2fb20b77
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/21/end_to_end_keys.sql
@@ -0,0 +1,34 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE IF NOT EXISTS e2e_device_keys_json (
+    user_id TEXT NOT NULL, -- The user these keys are for.
+    device_id TEXT NOT NULL, -- Which of the user's devices these keys are for.
+    ts_added_ms BIGINT NOT NULL, -- When the keys were uploaded.
+    key_json TEXT NOT NULL, -- The keys for the device as a JSON blob.
+    CONSTRAINT e2e_device_keys_json_uniqueness UNIQUE (user_id, device_id)
+);
+
+
+CREATE TABLE IF NOT EXISTS e2e_one_time_keys_json (
+    user_id TEXT NOT NULL, -- The user this one-time key is for.
+    device_id TEXT NOT NULL, -- The device this one-time key is for.
+    algorithm TEXT NOT NULL, -- Which algorithm this one-time key is for.
+    key_id TEXT NOT NULL, -- An id for suppressing duplicate uploads.
+    ts_added_ms BIGINT NOT NULL, -- When this key was uploaded.
+    key_json TEXT NOT NULL, -- The key as a JSON blob.
+    CONSTRAINT e2e_one_time_keys_json_uniqueness UNIQUE (user_id, device_id, algorithm, key_id)
+);
diff --git a/synapse/storage/databases/main/schema/delta/21/receipts.sql b/synapse/storage/databases/main/schema/delta/21/receipts.sql
new file mode 100644
index 0000000000..d070845477
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/21/receipts.sql
@@ -0,0 +1,38 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE IF NOT EXISTS receipts_graph(
+    room_id TEXT NOT NULL,
+    receipt_type TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    event_ids TEXT NOT NULL,
+    data TEXT NOT NULL,
+    CONSTRAINT receipts_graph_uniqueness UNIQUE (room_id, receipt_type, user_id)
+);
+
+CREATE TABLE IF NOT EXISTS receipts_linearized (
+    stream_id BIGINT NOT NULL,
+    room_id TEXT NOT NULL,
+    receipt_type TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    event_id TEXT NOT NULL,
+    data TEXT NOT NULL,
+    CONSTRAINT receipts_linearized_uniqueness UNIQUE (room_id, receipt_type, user_id)
+);
+
+CREATE INDEX receipts_linearized_id ON receipts_linearized(
+  stream_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/22/receipts_index.sql b/synapse/storage/databases/main/schema/delta/22/receipts_index.sql
new file mode 100644
index 0000000000..bfc0b3bcaa
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/22/receipts_index.sql
@@ -0,0 +1,22 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/** Using CREATE INDEX directly is deprecated in favour of using background
+ * update see synapse/storage/schema/delta/33/access_tokens_device_index.sql
+ * and synapse/storage/registration.py for an example using
+ * "access_tokens_device_index" **/
+CREATE INDEX receipts_linearized_room_stream ON receipts_linearized(
+    room_id, stream_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/22/user_threepids_unique.sql b/synapse/storage/databases/main/schema/delta/22/user_threepids_unique.sql
new file mode 100644
index 0000000000..87edfa454c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/22/user_threepids_unique.sql
@@ -0,0 +1,19 @@
+CREATE TABLE IF NOT EXISTS user_threepids2 (
+    user_id TEXT NOT NULL,
+    medium TEXT NOT NULL,
+    address TEXT NOT NULL,
+    validated_at BIGINT NOT NULL,
+    added_at BIGINT NOT NULL,
+    CONSTRAINT medium_address UNIQUE (medium, address)
+);
+
+INSERT INTO user_threepids2
+	SELECT * FROM user_threepids WHERE added_at IN (
+		SELECT max(added_at) FROM user_threepids GROUP BY medium, address
+	)
+;
+
+DROP TABLE user_threepids;
+ALTER TABLE user_threepids2 RENAME TO user_threepids;
+
+CREATE INDEX user_threepids_user_id ON user_threepids(user_id);
diff --git a/synapse/storage/databases/main/schema/delta/24/stats_reporting.sql b/synapse/storage/databases/main/schema/delta/24/stats_reporting.sql
new file mode 100644
index 0000000000..acea7483bd
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/24/stats_reporting.sql
@@ -0,0 +1,18 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ /* We used to create a table called stats_reporting, but this is no longer
+ * used and is removed in delta 54.
+ */
\ No newline at end of file
diff --git a/synapse/storage/databases/main/schema/delta/25/fts.py b/synapse/storage/databases/main/schema/delta/25/fts.py
new file mode 100644
index 0000000000..ee675e71ff
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/25/fts.py
@@ -0,0 +1,80 @@
+# Copyright 2015, 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import json
+import logging
+
+from synapse.storage.engines import PostgresEngine, Sqlite3Engine
+from synapse.storage.prepare_database import get_statements
+
+logger = logging.getLogger(__name__)
+
+
+POSTGRES_TABLE = """
+CREATE TABLE IF NOT EXISTS event_search (
+    event_id TEXT,
+    room_id TEXT,
+    sender TEXT,
+    key TEXT,
+    vector tsvector
+);
+
+CREATE INDEX event_search_fts_idx ON event_search USING gin(vector);
+CREATE INDEX event_search_ev_idx ON event_search(event_id);
+CREATE INDEX event_search_ev_ridx ON event_search(room_id);
+"""
+
+
+SQLITE_TABLE = (
+    "CREATE VIRTUAL TABLE event_search"
+    " USING fts4 ( event_id, room_id, sender, key, value )"
+)
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    if isinstance(database_engine, PostgresEngine):
+        for statement in get_statements(POSTGRES_TABLE.splitlines()):
+            cur.execute(statement)
+    elif isinstance(database_engine, Sqlite3Engine):
+        cur.execute(SQLITE_TABLE)
+    else:
+        raise Exception("Unrecognized database engine")
+
+    cur.execute("SELECT MIN(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    min_stream_id = rows[0][0]
+
+    cur.execute("SELECT MAX(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    max_stream_id = rows[0][0]
+
+    if min_stream_id is not None and max_stream_id is not None:
+        progress = {
+            "target_min_stream_id_inclusive": min_stream_id,
+            "max_stream_id_exclusive": max_stream_id + 1,
+            "rows_inserted": 0,
+        }
+        progress_json = json.dumps(progress)
+
+        sql = (
+            "INSERT into background_updates (update_name, progress_json)"
+            " VALUES (?, ?)"
+        )
+
+        sql = database_engine.convert_param_style(sql)
+
+        cur.execute(sql, ("event_search", progress_json))
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/25/guest_access.sql b/synapse/storage/databases/main/schema/delta/25/guest_access.sql
new file mode 100644
index 0000000000..1ea389b471
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/25/guest_access.sql
@@ -0,0 +1,25 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * This is a manual index of guest_access content of state events,
+ * so that we can join on them in SELECT statements.
+ */
+CREATE TABLE IF NOT EXISTS guest_access(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    guest_access TEXT NOT NULL,
+    UNIQUE (event_id)
+);
diff --git a/synapse/storage/databases/main/schema/delta/25/history_visibility.sql b/synapse/storage/databases/main/schema/delta/25/history_visibility.sql
new file mode 100644
index 0000000000..f468fc1897
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/25/history_visibility.sql
@@ -0,0 +1,25 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * This is a manual index of history_visibility content of state events,
+ * so that we can join on them in SELECT statements.
+ */
+CREATE TABLE IF NOT EXISTS history_visibility(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    history_visibility TEXT NOT NULL,
+    UNIQUE (event_id)
+);
diff --git a/synapse/storage/databases/main/schema/delta/25/tags.sql b/synapse/storage/databases/main/schema/delta/25/tags.sql
new file mode 100644
index 0000000000..7a32ce68e4
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/25/tags.sql
@@ -0,0 +1,38 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE IF NOT EXISTS room_tags(
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    tag     TEXT NOT NULL,  -- The name of the tag.
+    content TEXT NOT NULL,  -- The JSON content of the tag.
+    CONSTRAINT room_tag_uniqueness UNIQUE (user_id, room_id, tag)
+);
+
+CREATE TABLE IF NOT EXISTS room_tags_revisions (
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    stream_id BIGINT NOT NULL, -- The current version of the room tags.
+    CONSTRAINT room_tag_revisions_uniqueness UNIQUE (user_id, room_id)
+);
+
+CREATE TABLE IF NOT EXISTS private_user_data_max_stream_id(
+    Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE,  -- Makes sure this table only has one row.
+    stream_id  BIGINT NOT NULL,
+    CHECK (Lock='X')
+);
+
+INSERT INTO private_user_data_max_stream_id (stream_id) VALUES (0);
diff --git a/synapse/storage/databases/main/schema/delta/26/account_data.sql b/synapse/storage/databases/main/schema/delta/26/account_data.sql
new file mode 100644
index 0000000000..e395de2b5e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/26/account_data.sql
@@ -0,0 +1,17 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+ALTER TABLE private_user_data_max_stream_id RENAME TO account_data_max_stream_id;
diff --git a/synapse/storage/databases/main/schema/delta/27/account_data.sql b/synapse/storage/databases/main/schema/delta/27/account_data.sql
new file mode 100644
index 0000000000..bf0558b5b3
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/27/account_data.sql
@@ -0,0 +1,36 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS account_data(
+    user_id TEXT NOT NULL,
+    account_data_type TEXT NOT NULL, -- The type of the account_data.
+    stream_id BIGINT NOT NULL, -- The version of the account_data.
+    content TEXT NOT NULL,  -- The JSON content of the account_data
+    CONSTRAINT account_data_uniqueness UNIQUE (user_id, account_data_type)
+);
+
+
+CREATE TABLE IF NOT EXISTS room_account_data(
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    account_data_type TEXT NOT NULL, -- The type of the account_data.
+    stream_id BIGINT NOT NULL, -- The version of the account_data.
+    content TEXT NOT NULL,  -- The JSON content of the account_data
+    CONSTRAINT room_account_data_uniqueness UNIQUE (user_id, room_id, account_data_type)
+);
+
+
+CREATE INDEX account_data_stream_id on account_data(user_id, stream_id);
+CREATE INDEX room_account_data_stream_id on room_account_data(user_id, stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/27/forgotten_memberships.sql b/synapse/storage/databases/main/schema/delta/27/forgotten_memberships.sql
new file mode 100644
index 0000000000..e2094f37fe
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/27/forgotten_memberships.sql
@@ -0,0 +1,26 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Keeps track of what rooms users have left and don't want to be able to
+ * access again.
+ *
+ * If all users on this server have left a room, we can delete the room
+ * entirely.
+ *
+ * This column should always contain either 0 or 1.
+ */
+
+ ALTER TABLE room_memberships ADD COLUMN forgotten INTEGER DEFAULT 0;
diff --git a/synapse/storage/databases/main/schema/delta/27/ts.py b/synapse/storage/databases/main/schema/delta/27/ts.py
new file mode 100644
index 0000000000..b7972cfa8e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/27/ts.py
@@ -0,0 +1,59 @@
+# Copyright 2015, 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import json
+import logging
+
+from synapse.storage.prepare_database import get_statements
+
+logger = logging.getLogger(__name__)
+
+
+ALTER_TABLE = (
+    "ALTER TABLE events ADD COLUMN origin_server_ts BIGINT;"
+    "CREATE INDEX events_ts ON events(origin_server_ts, stream_ordering);"
+)
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    for statement in get_statements(ALTER_TABLE.splitlines()):
+        cur.execute(statement)
+
+    cur.execute("SELECT MIN(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    min_stream_id = rows[0][0]
+
+    cur.execute("SELECT MAX(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    max_stream_id = rows[0][0]
+
+    if min_stream_id is not None and max_stream_id is not None:
+        progress = {
+            "target_min_stream_id_inclusive": min_stream_id,
+            "max_stream_id_exclusive": max_stream_id + 1,
+            "rows_inserted": 0,
+        }
+        progress_json = json.dumps(progress)
+
+        sql = (
+            "INSERT into background_updates (update_name, progress_json)"
+            " VALUES (?, ?)"
+        )
+
+        sql = database_engine.convert_param_style(sql)
+
+        cur.execute(sql, ("event_origin_server_ts", progress_json))
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/28/event_push_actions.sql b/synapse/storage/databases/main/schema/delta/28/event_push_actions.sql
new file mode 100644
index 0000000000..4d519849df
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/28/event_push_actions.sql
@@ -0,0 +1,27 @@
+/* Copyright 2015 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS event_push_actions(
+    room_id TEXT NOT NULL,
+    event_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    profile_tag VARCHAR(32),
+    actions TEXT NOT NULL,
+    CONSTRAINT event_id_user_id_profile_tag_uniqueness UNIQUE (room_id, event_id, user_id, profile_tag)
+);
+
+
+CREATE INDEX event_push_actions_room_id_event_id_user_id_profile_tag on event_push_actions(room_id, event_id, user_id, profile_tag);
+CREATE INDEX event_push_actions_room_id_user_id on event_push_actions(room_id, user_id);
diff --git a/synapse/storage/databases/main/schema/delta/28/events_room_stream.sql b/synapse/storage/databases/main/schema/delta/28/events_room_stream.sql
new file mode 100644
index 0000000000..36609475f1
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/28/events_room_stream.sql
@@ -0,0 +1,20 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+*/
+
+/** Using CREATE INDEX directly is deprecated in favour of using background
+ * update see synapse/storage/schema/delta/33/access_tokens_device_index.sql
+ * and synapse/storage/registration.py for an example using
+ * "access_tokens_device_index" **/
+CREATE INDEX events_room_stream on events(room_id, stream_ordering);
diff --git a/synapse/storage/databases/main/schema/delta/28/public_roms_index.sql b/synapse/storage/databases/main/schema/delta/28/public_roms_index.sql
new file mode 100644
index 0000000000..6c1fd68c5b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/28/public_roms_index.sql
@@ -0,0 +1,20 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+*/
+
+/** Using CREATE INDEX directly is deprecated in favour of using background
+ * update see synapse/storage/schema/delta/33/access_tokens_device_index.sql
+ * and synapse/storage/registration.py for an example using
+ * "access_tokens_device_index" **/
+CREATE INDEX public_room_index on rooms(is_public);
diff --git a/synapse/storage/databases/main/schema/delta/28/receipts_user_id_index.sql b/synapse/storage/databases/main/schema/delta/28/receipts_user_id_index.sql
new file mode 100644
index 0000000000..cb84c69baa
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/28/receipts_user_id_index.sql
@@ -0,0 +1,22 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/** Using CREATE INDEX directly is deprecated in favour of using background
+ * update see synapse/storage/schema/delta/33/access_tokens_device_index.sql
+ * and synapse/storage/registration.py for an example using
+ * "access_tokens_device_index" **/
+CREATE INDEX receipts_linearized_user ON receipts_linearized(
+    user_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/28/upgrade_times.sql b/synapse/storage/databases/main/schema/delta/28/upgrade_times.sql
new file mode 100644
index 0000000000..3e4a9ab455
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/28/upgrade_times.sql
@@ -0,0 +1,21 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Stores the timestamp when a user upgraded from a guest to a full user, if
+ * that happened.
+ */
+
+ALTER TABLE users ADD COLUMN upgrade_ts BIGINT;
diff --git a/synapse/storage/databases/main/schema/delta/28/users_is_guest.sql b/synapse/storage/databases/main/schema/delta/28/users_is_guest.sql
new file mode 100644
index 0000000000..21d2b420bf
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/28/users_is_guest.sql
@@ -0,0 +1,22 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE users ADD is_guest SMALLINT DEFAULT 0 NOT NULL;
+/*
+ * NB: any guest users created between 27 and 28 will be incorrectly
+ * marked as not guests: we don't bother to fill these in correctly
+ * because guest access is not really complete in 27 anyway so it's
+ * very unlikley there will be any guest users created.
+ */
diff --git a/synapse/storage/databases/main/schema/delta/29/push_actions.sql b/synapse/storage/databases/main/schema/delta/29/push_actions.sql
new file mode 100644
index 0000000000..84b21cf813
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/29/push_actions.sql
@@ -0,0 +1,35 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE event_push_actions ADD COLUMN topological_ordering BIGINT;
+ALTER TABLE event_push_actions ADD COLUMN stream_ordering BIGINT;
+ALTER TABLE event_push_actions ADD COLUMN notif SMALLINT;
+ALTER TABLE event_push_actions ADD COLUMN highlight SMALLINT;
+
+UPDATE event_push_actions SET stream_ordering = (
+    SELECT stream_ordering FROM events WHERE event_id = event_push_actions.event_id
+), topological_ordering = (
+    SELECT topological_ordering FROM events WHERE event_id = event_push_actions.event_id
+);
+
+UPDATE event_push_actions SET notif = 1, highlight = 0;
+
+/** Using CREATE INDEX directly is deprecated in favour of using background
+ * update see synapse/storage/schema/delta/33/access_tokens_device_index.sql
+ * and synapse/storage/registration.py for an example using
+ * "access_tokens_device_index" **/
+CREATE INDEX event_push_actions_rm_tokens on event_push_actions(
+    user_id, room_id, topological_ordering, stream_ordering
+);
diff --git a/synapse/storage/databases/main/schema/delta/30/alias_creator.sql b/synapse/storage/databases/main/schema/delta/30/alias_creator.sql
new file mode 100644
index 0000000000..c9d0dde638
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/30/alias_creator.sql
@@ -0,0 +1,16 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE room_aliases ADD COLUMN creator TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/30/as_users.py b/synapse/storage/databases/main/schema/delta/30/as_users.py
new file mode 100644
index 0000000000..b42c02710a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/30/as_users.py
@@ -0,0 +1,67 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import logging
+
+from synapse.config.appservice import load_appservices
+
+logger = logging.getLogger(__name__)
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    # NULL indicates user was not registered by an appservice.
+    try:
+        cur.execute("ALTER TABLE users ADD COLUMN appservice_id TEXT")
+    except Exception:
+        # Maybe we already added the column? Hope so...
+        pass
+
+
+def run_upgrade(cur, database_engine, config, *args, **kwargs):
+    cur.execute("SELECT name FROM users")
+    rows = cur.fetchall()
+
+    config_files = []
+    try:
+        config_files = config.app_service_config_files
+    except AttributeError:
+        logger.warning("Could not get app_service_config_files from config")
+        pass
+
+    appservices = load_appservices(config.server_name, config_files)
+
+    owned = {}
+
+    for row in rows:
+        user_id = row[0]
+        for appservice in appservices:
+            if appservice.is_exclusive_user(user_id):
+                if user_id in owned.keys():
+                    logger.error(
+                        "user_id %s was owned by more than one application"
+                        " service (IDs %s and %s); assigning arbitrarily to %s"
+                        % (user_id, owned[user_id], appservice.id, owned[user_id])
+                    )
+                owned.setdefault(appservice.id, []).append(user_id)
+
+    for as_id, user_ids in owned.items():
+        n = 100
+        user_chunks = (user_ids[i : i + 100] for i in range(0, len(user_ids), n))
+        for chunk in user_chunks:
+            cur.execute(
+                database_engine.convert_param_style(
+                    "UPDATE users SET appservice_id = ? WHERE name IN (%s)"
+                    % (",".join("?" for _ in chunk),)
+                ),
+                [as_id] + chunk,
+            )
diff --git a/synapse/storage/databases/main/schema/delta/30/deleted_pushers.sql b/synapse/storage/databases/main/schema/delta/30/deleted_pushers.sql
new file mode 100644
index 0000000000..712c454aa1
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/30/deleted_pushers.sql
@@ -0,0 +1,25 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS deleted_pushers(
+    stream_id BIGINT NOT NULL,
+    app_id TEXT NOT NULL,
+    pushkey TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    /* We only track the most recent delete for each app_id, pushkey and user_id. */
+    UNIQUE (app_id, pushkey, user_id)
+);
+
+CREATE INDEX deleted_pushers_stream_id ON deleted_pushers (stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/30/presence_stream.sql b/synapse/storage/databases/main/schema/delta/30/presence_stream.sql
new file mode 100644
index 0000000000..606bbb037d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/30/presence_stream.sql
@@ -0,0 +1,30 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+ CREATE TABLE presence_stream(
+     stream_id BIGINT,
+     user_id TEXT,
+     state TEXT,
+     last_active_ts BIGINT,
+     last_federation_update_ts BIGINT,
+     last_user_sync_ts BIGINT,
+     status_msg TEXT,
+     currently_active BOOLEAN
+ );
+
+ CREATE INDEX presence_stream_id ON presence_stream(stream_id, user_id);
+ CREATE INDEX presence_stream_user_id ON presence_stream(user_id);
+ CREATE INDEX presence_stream_state ON presence_stream(state);
diff --git a/synapse/storage/databases/main/schema/delta/30/public_rooms.sql b/synapse/storage/databases/main/schema/delta/30/public_rooms.sql
new file mode 100644
index 0000000000..f09db4faa6
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/30/public_rooms.sql
@@ -0,0 +1,23 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+/* This release removes the restriction that published rooms must have an alias,
+ * so we go back and ensure the only 'public' rooms are ones with an alias.
+ * We use (1 = 0) and (1 = 1) so that it works in both postgres and sqlite
+ */
+UPDATE rooms SET is_public = (1 = 0) WHERE is_public = (1 = 1) AND room_id not in (
+    SELECT room_id FROM room_aliases
+);
diff --git a/synapse/storage/databases/main/schema/delta/30/push_rule_stream.sql b/synapse/storage/databases/main/schema/delta/30/push_rule_stream.sql
new file mode 100644
index 0000000000..735aa8d5f6
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/30/push_rule_stream.sql
@@ -0,0 +1,38 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+
+CREATE TABLE push_rules_stream(
+    stream_id BIGINT NOT NULL,
+    event_stream_ordering BIGINT NOT NULL,
+    user_id TEXT NOT NULL,
+    rule_id TEXT NOT NULL,
+    op TEXT NOT NULL, -- One of "ENABLE", "DISABLE", "ACTIONS", "ADD", "DELETE"
+    priority_class SMALLINT,
+    priority INTEGER,
+    conditions TEXT,
+    actions TEXT
+);
+
+-- The extra data for each operation is:
+-- * ENABLE, DISABLE, DELETE: []
+-- * ACTIONS: ["actions"]
+-- * ADD: ["priority_class", "priority", "actions", "conditions"]
+
+-- Index for replication queries.
+CREATE INDEX push_rules_stream_id ON push_rules_stream(stream_id);
+-- Index for /sync queries.
+CREATE INDEX push_rules_stream_user_stream_id on push_rules_stream(user_id, stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/30/threepid_guest_access_tokens.sql b/synapse/storage/databases/main/schema/delta/30/threepid_guest_access_tokens.sql
new file mode 100644
index 0000000000..0dd2f1360c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/30/threepid_guest_access_tokens.sql
@@ -0,0 +1,24 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Stores guest account access tokens generated for unbound 3pids.
+CREATE TABLE threepid_guest_access_tokens(
+    medium TEXT, -- The medium of the 3pid. Must be "email".
+    address TEXT, -- The 3pid address.
+    guest_access_token TEXT, -- The access token for a guest user for this 3pid.
+    first_inviter TEXT -- User ID of the first user to invite this 3pid to a room.
+);
+
+CREATE UNIQUE INDEX threepid_guest_access_tokens_index ON threepid_guest_access_tokens(medium, address);
diff --git a/synapse/storage/databases/main/schema/delta/31/invites.sql b/synapse/storage/databases/main/schema/delta/31/invites.sql
new file mode 100644
index 0000000000..2c57846d5a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/31/invites.sql
@@ -0,0 +1,42 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE local_invites(
+    stream_id BIGINT NOT NULL,
+    inviter TEXT NOT NULL,
+    invitee TEXT NOT NULL,
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    locally_rejected TEXT,
+    replaced_by TEXT
+);
+
+-- Insert all invites for local users into new `invites` table
+INSERT INTO local_invites SELECT
+        stream_ordering as stream_id,
+        sender as inviter,
+        state_key as invitee,
+        event_id,
+        room_id,
+        NULL as locally_rejected,
+        NULL as replaced_by
+    FROM events
+    NATURAL JOIN current_state_events
+    NATURAL JOIN room_memberships
+    WHERE membership = 'invite'  AND state_key IN (SELECT name FROM users);
+
+CREATE INDEX local_invites_id ON local_invites(stream_id);
+CREATE INDEX local_invites_for_user_idx ON local_invites(invitee, locally_rejected, replaced_by, room_id);
diff --git a/synapse/storage/databases/main/schema/delta/31/local_media_repository_url_cache.sql b/synapse/storage/databases/main/schema/delta/31/local_media_repository_url_cache.sql
new file mode 100644
index 0000000000..9efb4280eb
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/31/local_media_repository_url_cache.sql
@@ -0,0 +1,27 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE local_media_repository_url_cache(
+    url TEXT,              -- the URL being cached
+    response_code INTEGER, -- the HTTP response code of this download attempt
+    etag TEXT,             -- the etag header of this response
+    expires INTEGER,       -- the number of ms this response was valid for
+    og TEXT,               -- cache of the OG metadata of this URL as JSON
+    media_id TEXT,         -- the media_id, if any, of the URL's content in the repo
+    download_ts BIGINT     -- the timestamp of this download attempt
+);
+
+CREATE INDEX local_media_repository_url_cache_by_url_download_ts
+    ON local_media_repository_url_cache(url, download_ts);
diff --git a/synapse/storage/databases/main/schema/delta/31/pushers.py b/synapse/storage/databases/main/schema/delta/31/pushers.py
new file mode 100644
index 0000000000..9bb504aad5
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/31/pushers.py
@@ -0,0 +1,87 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+# Change the last_token to last_stream_ordering now that pushers no longer
+# listen on an event stream but instead select out of the event_push_actions
+# table.
+
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+def token_to_stream_ordering(token):
+    return int(token[1:].split("_")[0])
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    logger.info("Porting pushers table, delta 31...")
+    cur.execute(
+        """
+        CREATE TABLE IF NOT EXISTS pushers2 (
+          id BIGINT PRIMARY KEY,
+          user_name TEXT NOT NULL,
+          access_token BIGINT DEFAULT NULL,
+          profile_tag VARCHAR(32) NOT NULL,
+          kind VARCHAR(8) NOT NULL,
+          app_id VARCHAR(64) NOT NULL,
+          app_display_name VARCHAR(64) NOT NULL,
+          device_display_name VARCHAR(128) NOT NULL,
+          pushkey TEXT NOT NULL,
+          ts BIGINT NOT NULL,
+          lang VARCHAR(8),
+          data TEXT,
+          last_stream_ordering INTEGER,
+          last_success BIGINT,
+          failing_since BIGINT,
+          UNIQUE (app_id, pushkey, user_name)
+        )
+    """
+    )
+    cur.execute(
+        """SELECT
+        id, user_name, access_token, profile_tag, kind,
+        app_id, app_display_name, device_display_name,
+        pushkey, ts, lang, data, last_token, last_success,
+        failing_since
+        FROM pushers
+    """
+    )
+    count = 0
+    for row in cur.fetchall():
+        row = list(row)
+        row[12] = token_to_stream_ordering(row[12])
+        cur.execute(
+            database_engine.convert_param_style(
+                """
+            INSERT into pushers2 (
+            id, user_name, access_token, profile_tag, kind,
+            app_id, app_display_name, device_display_name,
+            pushkey, ts, lang, data, last_stream_ordering, last_success,
+            failing_since
+            ) values (%s)"""
+                % (",".join(["?" for _ in range(len(row))]))
+            ),
+            row,
+        )
+        count += 1
+    cur.execute("DROP TABLE pushers")
+    cur.execute("ALTER TABLE pushers2 RENAME TO pushers")
+    logger.info("Moved %d pushers to new table", count)
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/31/pushers_index.sql b/synapse/storage/databases/main/schema/delta/31/pushers_index.sql
new file mode 100644
index 0000000000..a82add88fd
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/31/pushers_index.sql
@@ -0,0 +1,22 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/** Using CREATE INDEX directly is deprecated in favour of using background
+ * update see synapse/storage/schema/delta/33/access_tokens_device_index.sql
+ * and synapse/storage/registration.py for an example using
+ * "access_tokens_device_index" **/
+ CREATE INDEX event_push_actions_stream_ordering on event_push_actions(
+     stream_ordering, user_id
+ );
diff --git a/synapse/storage/databases/main/schema/delta/31/search_update.py b/synapse/storage/databases/main/schema/delta/31/search_update.py
new file mode 100644
index 0000000000..63b757ade6
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/31/search_update.py
@@ -0,0 +1,64 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import json
+import logging
+
+from synapse.storage.engines import PostgresEngine
+from synapse.storage.prepare_database import get_statements
+
+logger = logging.getLogger(__name__)
+
+
+ALTER_TABLE = """
+ALTER TABLE event_search ADD COLUMN origin_server_ts BIGINT;
+ALTER TABLE event_search ADD COLUMN stream_ordering BIGINT;
+"""
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    if not isinstance(database_engine, PostgresEngine):
+        return
+
+    for statement in get_statements(ALTER_TABLE.splitlines()):
+        cur.execute(statement)
+
+    cur.execute("SELECT MIN(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    min_stream_id = rows[0][0]
+
+    cur.execute("SELECT MAX(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    max_stream_id = rows[0][0]
+
+    if min_stream_id is not None and max_stream_id is not None:
+        progress = {
+            "target_min_stream_id_inclusive": min_stream_id,
+            "max_stream_id_exclusive": max_stream_id + 1,
+            "rows_inserted": 0,
+            "have_added_indexes": False,
+        }
+        progress_json = json.dumps(progress)
+
+        sql = (
+            "INSERT into background_updates (update_name, progress_json)"
+            " VALUES (?, ?)"
+        )
+
+        sql = database_engine.convert_param_style(sql)
+
+        cur.execute(sql, ("event_search_order", progress_json))
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/32/events.sql b/synapse/storage/databases/main/schema/delta/32/events.sql
new file mode 100644
index 0000000000..1dd0f9e170
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/32/events.sql
@@ -0,0 +1,16 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE events ADD COLUMN received_ts BIGINT;
diff --git a/synapse/storage/databases/main/schema/delta/32/openid.sql b/synapse/storage/databases/main/schema/delta/32/openid.sql
new file mode 100644
index 0000000000..36f37b11c8
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/32/openid.sql
@@ -0,0 +1,9 @@
+
+CREATE TABLE open_id_tokens (
+    token TEXT NOT NULL PRIMARY KEY,
+    ts_valid_until_ms bigint NOT NULL,
+    user_id TEXT NOT NULL,
+    UNIQUE (token)
+);
+
+CREATE index open_id_tokens_ts_valid_until_ms ON open_id_tokens(ts_valid_until_ms);
diff --git a/synapse/storage/databases/main/schema/delta/32/pusher_throttle.sql b/synapse/storage/databases/main/schema/delta/32/pusher_throttle.sql
new file mode 100644
index 0000000000..d86d30c13c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/32/pusher_throttle.sql
@@ -0,0 +1,23 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE pusher_throttle(
+    pusher BIGINT NOT NULL,
+    room_id TEXT NOT NULL,
+    last_sent_ts BIGINT,
+    throttle_ms BIGINT,
+    PRIMARY KEY (pusher, room_id)
+);
diff --git a/synapse/storage/databases/main/schema/delta/32/remove_indices.sql b/synapse/storage/databases/main/schema/delta/32/remove_indices.sql
new file mode 100644
index 0000000000..2de50d408c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/32/remove_indices.sql
@@ -0,0 +1,33 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+-- The following indices are redundant, other indices are equivalent or
+-- supersets
+DROP INDEX IF EXISTS events_room_id; -- Prefix of events_room_stream
+DROP INDEX IF EXISTS events_order; -- Prefix of events_order_topo_stream_room
+DROP INDEX IF EXISTS events_topological_ordering; -- Prefix of events_order_topo_stream_room
+DROP INDEX IF EXISTS events_stream_ordering; -- Duplicate of PRIMARY KEY
+DROP INDEX IF EXISTS event_to_state_groups_id; -- Duplicate of PRIMARY KEY
+DROP INDEX IF EXISTS event_push_actions_room_id_event_id_user_id_profile_tag; -- Duplicate of UNIQUE CONSTRAINT
+
+DROP INDEX IF EXISTS st_extrem_id; -- Prefix of UNIQUE CONSTRAINT
+DROP INDEX IF EXISTS event_signatures_id; -- Prefix of UNIQUE CONSTRAINT
+DROP INDEX IF EXISTS redactions_event_id; -- Duplicate of UNIQUE CONSTRAINT
+
+-- The following indices were unused
+DROP INDEX IF EXISTS remote_media_cache_thumbnails_media_id;
+DROP INDEX IF EXISTS evauth_edges_auth_id;
+DROP INDEX IF EXISTS presence_stream_state;
diff --git a/synapse/storage/databases/main/schema/delta/32/reports.sql b/synapse/storage/databases/main/schema/delta/32/reports.sql
new file mode 100644
index 0000000000..d13609776f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/32/reports.sql
@@ -0,0 +1,25 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE event_reports(
+    id BIGINT NOT NULL PRIMARY KEY,
+    received_ts BIGINT NOT NULL,
+    room_id TEXT NOT NULL,
+    event_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    reason TEXT,
+    content TEXT
+);
diff --git a/synapse/storage/databases/main/schema/delta/33/access_tokens_device_index.sql b/synapse/storage/databases/main/schema/delta/33/access_tokens_device_index.sql
new file mode 100644
index 0000000000..61ad3fe3e8
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/33/access_tokens_device_index.sql
@@ -0,0 +1,17 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('access_tokens_device_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/33/devices.sql b/synapse/storage/databases/main/schema/delta/33/devices.sql
new file mode 100644
index 0000000000..eca7268d82
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/33/devices.sql
@@ -0,0 +1,21 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE devices (
+    user_id TEXT NOT NULL,
+    device_id TEXT NOT NULL,
+    display_name TEXT,
+    CONSTRAINT device_uniqueness UNIQUE (user_id, device_id)
+);
diff --git a/synapse/storage/databases/main/schema/delta/33/devices_for_e2e_keys.sql b/synapse/storage/databases/main/schema/delta/33/devices_for_e2e_keys.sql
new file mode 100644
index 0000000000..aa4a3b9f2f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/33/devices_for_e2e_keys.sql
@@ -0,0 +1,19 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- make sure that we have a device record for each set of E2E keys, so that the
+-- user can delete them if they like.
+INSERT INTO devices
+    SELECT user_id, device_id, NULL FROM e2e_device_keys_json;
diff --git a/synapse/storage/databases/main/schema/delta/33/devices_for_e2e_keys_clear_unknown_device.sql b/synapse/storage/databases/main/schema/delta/33/devices_for_e2e_keys_clear_unknown_device.sql
new file mode 100644
index 0000000000..6671573398
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/33/devices_for_e2e_keys_clear_unknown_device.sql
@@ -0,0 +1,20 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- a previous version of the "devices_for_e2e_keys" delta set all the device
+-- names to "unknown device". This wasn't terribly helpful
+UPDATE devices
+    SET display_name = NULL
+    WHERE display_name = 'unknown device';
diff --git a/synapse/storage/databases/main/schema/delta/33/event_fields.py b/synapse/storage/databases/main/schema/delta/33/event_fields.py
new file mode 100644
index 0000000000..a3e81eeac7
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/33/event_fields.py
@@ -0,0 +1,59 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import json
+import logging
+
+from synapse.storage.prepare_database import get_statements
+
+logger = logging.getLogger(__name__)
+
+
+ALTER_TABLE = """
+ALTER TABLE events ADD COLUMN sender TEXT;
+ALTER TABLE events ADD COLUMN contains_url BOOLEAN;
+"""
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    for statement in get_statements(ALTER_TABLE.splitlines()):
+        cur.execute(statement)
+
+    cur.execute("SELECT MIN(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    min_stream_id = rows[0][0]
+
+    cur.execute("SELECT MAX(stream_ordering) FROM events")
+    rows = cur.fetchall()
+    max_stream_id = rows[0][0]
+
+    if min_stream_id is not None and max_stream_id is not None:
+        progress = {
+            "target_min_stream_id_inclusive": min_stream_id,
+            "max_stream_id_exclusive": max_stream_id + 1,
+            "rows_inserted": 0,
+        }
+        progress_json = json.dumps(progress)
+
+        sql = (
+            "INSERT into background_updates (update_name, progress_json)"
+            " VALUES (?, ?)"
+        )
+
+        sql = database_engine.convert_param_style(sql)
+
+        cur.execute(sql, ("event_fields_sender_url", progress_json))
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/33/remote_media_ts.py b/synapse/storage/databases/main/schema/delta/33/remote_media_ts.py
new file mode 100644
index 0000000000..a26057dfb6
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/33/remote_media_ts.py
@@ -0,0 +1,30 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import time
+
+ALTER_TABLE = "ALTER TABLE remote_media_cache ADD COLUMN last_access_ts BIGINT"
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    cur.execute(ALTER_TABLE)
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    cur.execute(
+        database_engine.convert_param_style(
+            "UPDATE remote_media_cache SET last_access_ts = ?"
+        ),
+        (int(time.time() * 1000),),
+    )
diff --git a/synapse/storage/databases/main/schema/delta/33/user_ips_index.sql b/synapse/storage/databases/main/schema/delta/33/user_ips_index.sql
new file mode 100644
index 0000000000..473f75a78e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/33/user_ips_index.sql
@@ -0,0 +1,17 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('user_ips_device_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/34/appservice_stream.sql b/synapse/storage/databases/main/schema/delta/34/appservice_stream.sql
new file mode 100644
index 0000000000..69e16eda0f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/34/appservice_stream.sql
@@ -0,0 +1,23 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS appservice_stream_position(
+    Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE,  -- Makes sure this table only has one row.
+    stream_ordering BIGINT,
+    CHECK (Lock='X')
+);
+
+INSERT INTO appservice_stream_position (stream_ordering)
+    SELECT COALESCE(MAX(stream_ordering), 0) FROM events;
diff --git a/synapse/storage/databases/main/schema/delta/34/cache_stream.py b/synapse/storage/databases/main/schema/delta/34/cache_stream.py
new file mode 100644
index 0000000000..cf09e43e2b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/34/cache_stream.py
@@ -0,0 +1,46 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from synapse.storage.engines import PostgresEngine
+from synapse.storage.prepare_database import get_statements
+
+logger = logging.getLogger(__name__)
+
+
+# This stream is used to notify replication slaves that some caches have
+# been invalidated that they cannot infer from the other streams.
+CREATE_TABLE = """
+CREATE TABLE cache_invalidation_stream (
+    stream_id       BIGINT,
+    cache_func      TEXT,
+    keys            TEXT[],
+    invalidation_ts BIGINT
+);
+
+CREATE INDEX cache_invalidation_stream_id ON cache_invalidation_stream(stream_id);
+"""
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    if not isinstance(database_engine, PostgresEngine):
+        return
+
+    for statement in get_statements(CREATE_TABLE.splitlines()):
+        cur.execute(statement)
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/34/device_inbox.sql b/synapse/storage/databases/main/schema/delta/34/device_inbox.sql
new file mode 100644
index 0000000000..e68844c74a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/34/device_inbox.sql
@@ -0,0 +1,24 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE device_inbox (
+    user_id TEXT NOT NULL,
+    device_id TEXT NOT NULL,
+    stream_id BIGINT NOT NULL,
+    message_json TEXT NOT NULL -- {"type":, "sender":, "content",}
+);
+
+CREATE INDEX device_inbox_user_stream_id ON device_inbox(user_id, device_id, stream_id);
+CREATE INDEX device_inbox_stream_id ON device_inbox(stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/34/push_display_name_rename.sql b/synapse/storage/databases/main/schema/delta/34/push_display_name_rename.sql
new file mode 100644
index 0000000000..0d9fe1a99a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/34/push_display_name_rename.sql
@@ -0,0 +1,20 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+DELETE FROM push_rules WHERE rule_id = 'global/override/.m.rule.contains_display_name';
+UPDATE push_rules SET rule_id = 'global/override/.m.rule.contains_display_name' WHERE rule_id = 'global/underride/.m.rule.contains_display_name';
+
+DELETE FROM push_rules_enable WHERE rule_id = 'global/override/.m.rule.contains_display_name';
+UPDATE push_rules_enable SET rule_id = 'global/override/.m.rule.contains_display_name' WHERE rule_id = 'global/underride/.m.rule.contains_display_name';
diff --git a/synapse/storage/databases/main/schema/delta/34/received_txn_purge.py b/synapse/storage/databases/main/schema/delta/34/received_txn_purge.py
new file mode 100644
index 0000000000..67d505e68b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/34/received_txn_purge.py
@@ -0,0 +1,32 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from synapse.storage.engines import PostgresEngine
+
+logger = logging.getLogger(__name__)
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    if isinstance(database_engine, PostgresEngine):
+        cur.execute("TRUNCATE received_transactions")
+    else:
+        cur.execute("DELETE FROM received_transactions")
+
+    cur.execute("CREATE INDEX received_transactions_ts ON received_transactions(ts)")
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/35/contains_url.sql b/synapse/storage/databases/main/schema/delta/35/contains_url.sql
new file mode 100644
index 0000000000..6cd123027b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/35/contains_url.sql
@@ -0,0 +1,17 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ INSERT into background_updates (update_name, progress_json)
+     VALUES ('event_contains_url_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/35/device_outbox.sql b/synapse/storage/databases/main/schema/delta/35/device_outbox.sql
new file mode 100644
index 0000000000..17e6c43105
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/35/device_outbox.sql
@@ -0,0 +1,39 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+DROP TABLE IF EXISTS device_federation_outbox;
+CREATE TABLE device_federation_outbox (
+    destination TEXT NOT NULL,
+    stream_id BIGINT NOT NULL,
+    queued_ts BIGINT NOT NULL,
+    messages_json TEXT NOT NULL
+);
+
+
+DROP INDEX IF EXISTS device_federation_outbox_destination_id;
+CREATE INDEX device_federation_outbox_destination_id
+    ON device_federation_outbox(destination, stream_id);
+
+
+DROP TABLE IF EXISTS device_federation_inbox;
+CREATE TABLE device_federation_inbox (
+    origin TEXT NOT NULL,
+    message_id TEXT NOT NULL,
+    received_ts BIGINT NOT NULL
+);
+
+DROP INDEX IF EXISTS device_federation_inbox_sender_id;
+CREATE INDEX device_federation_inbox_sender_id
+    ON device_federation_inbox(origin, message_id);
diff --git a/synapse/storage/databases/main/schema/delta/35/device_stream_id.sql b/synapse/storage/databases/main/schema/delta/35/device_stream_id.sql
new file mode 100644
index 0000000000..7ab7d942e2
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/35/device_stream_id.sql
@@ -0,0 +1,21 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE device_max_stream_id (
+    stream_id BIGINT NOT NULL
+);
+
+INSERT INTO device_max_stream_id (stream_id)
+    SELECT COALESCE(MAX(stream_id), 0) FROM device_inbox;
diff --git a/synapse/storage/databases/main/schema/delta/35/event_push_actions_index.sql b/synapse/storage/databases/main/schema/delta/35/event_push_actions_index.sql
new file mode 100644
index 0000000000..2e836d8e9c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/35/event_push_actions_index.sql
@@ -0,0 +1,17 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ INSERT into background_updates (update_name, progress_json)
+     VALUES ('epa_highlight_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/35/public_room_list_change_stream.sql b/synapse/storage/databases/main/schema/delta/35/public_room_list_change_stream.sql
new file mode 100644
index 0000000000..dd2bf2e28a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/35/public_room_list_change_stream.sql
@@ -0,0 +1,33 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE public_room_list_stream (
+    stream_id BIGINT NOT NULL,
+    room_id TEXT NOT NULL,
+    visibility BOOLEAN NOT NULL
+);
+
+INSERT INTO public_room_list_stream (stream_id, room_id, visibility)
+    SELECT 1, room_id, is_public FROM rooms
+    WHERE is_public = CAST(1 AS BOOLEAN);
+
+CREATE INDEX public_room_list_stream_idx on public_room_list_stream(
+    stream_id
+);
+
+CREATE INDEX public_room_list_stream_rm_idx on public_room_list_stream(
+    room_id, stream_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/35/stream_order_to_extrem.sql b/synapse/storage/databases/main/schema/delta/35/stream_order_to_extrem.sql
new file mode 100644
index 0000000000..2b945d8a57
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/35/stream_order_to_extrem.sql
@@ -0,0 +1,37 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE stream_ordering_to_exterm (
+    stream_ordering BIGINT NOT NULL,
+    room_id TEXT NOT NULL,
+    event_id TEXT NOT NULL
+);
+
+INSERT INTO stream_ordering_to_exterm (stream_ordering, room_id, event_id)
+    SELECT stream_ordering, room_id, event_id FROM event_forward_extremities
+    INNER JOIN (
+        SELECT room_id, max(stream_ordering) as stream_ordering FROM events
+        INNER JOIN event_forward_extremities USING (room_id, event_id)
+        GROUP BY room_id
+    ) AS rms USING (room_id);
+
+CREATE INDEX stream_ordering_to_exterm_idx on stream_ordering_to_exterm(
+    stream_ordering
+);
+
+CREATE INDEX stream_ordering_to_exterm_rm_idx on stream_ordering_to_exterm(
+    room_id, stream_ordering
+);
diff --git a/synapse/storage/databases/main/schema/delta/36/readd_public_rooms.sql b/synapse/storage/databases/main/schema/delta/36/readd_public_rooms.sql
new file mode 100644
index 0000000000..90d8fd18f9
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/36/readd_public_rooms.sql
@@ -0,0 +1,26 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Re-add some entries to stream_ordering_to_exterm that were incorrectly deleted
+INSERT INTO stream_ordering_to_exterm (stream_ordering, room_id, event_id)
+    SELECT
+        (SELECT stream_ordering FROM events where event_id = e.event_id) AS stream_ordering,
+        room_id,
+        event_id
+    FROM event_forward_extremities AS e
+    WHERE NOT EXISTS (
+        SELECT room_id FROM stream_ordering_to_exterm AS s
+        WHERE s.room_id = e.room_id
+    );
diff --git a/synapse/storage/databases/main/schema/delta/37/remove_auth_idx.py b/synapse/storage/databases/main/schema/delta/37/remove_auth_idx.py
new file mode 100644
index 0000000000..a377884169
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/37/remove_auth_idx.py
@@ -0,0 +1,85 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from synapse.storage.engines import PostgresEngine
+from synapse.storage.prepare_database import get_statements
+
+logger = logging.getLogger(__name__)
+
+DROP_INDICES = """
+-- We only ever query based on event_id
+DROP INDEX IF EXISTS state_events_room_id;
+DROP INDEX IF EXISTS state_events_type;
+DROP INDEX IF EXISTS state_events_state_key;
+
+-- room_id is indexed elsewhere
+DROP INDEX IF EXISTS current_state_events_room_id;
+DROP INDEX IF EXISTS current_state_events_state_key;
+DROP INDEX IF EXISTS current_state_events_type;
+
+DROP INDEX IF EXISTS transactions_have_ref;
+
+-- (topological_ordering, stream_ordering, room_id) seems like a strange index,
+-- and is used incredibly rarely.
+DROP INDEX IF EXISTS events_order_topo_stream_room;
+
+-- an equivalent index to this actually gets re-created in delta 41, because it
+-- turned out that deleting it wasn't a great plan :/. In any case, let's
+-- delete it here, and delta 41 will create a new one with an added UNIQUE
+-- constraint
+DROP INDEX IF EXISTS event_search_ev_idx;
+"""
+
+POSTGRES_DROP_CONSTRAINT = """
+ALTER TABLE event_auth DROP CONSTRAINT IF EXISTS event_auth_event_id_auth_id_room_id_key;
+"""
+
+SQLITE_DROP_CONSTRAINT = """
+DROP INDEX IF EXISTS evauth_edges_id;
+
+CREATE TABLE IF NOT EXISTS event_auth_new(
+    event_id TEXT NOT NULL,
+    auth_id TEXT NOT NULL,
+    room_id TEXT NOT NULL
+);
+
+INSERT INTO event_auth_new
+    SELECT event_id, auth_id, room_id
+    FROM event_auth;
+
+DROP TABLE event_auth;
+
+ALTER TABLE event_auth_new RENAME TO event_auth;
+
+CREATE INDEX evauth_edges_id ON event_auth(event_id);
+"""
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    for statement in get_statements(DROP_INDICES.splitlines()):
+        cur.execute(statement)
+
+    if isinstance(database_engine, PostgresEngine):
+        drop_constraint = POSTGRES_DROP_CONSTRAINT
+    else:
+        drop_constraint = SQLITE_DROP_CONSTRAINT
+
+    for statement in get_statements(drop_constraint.splitlines()):
+        cur.execute(statement)
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/37/user_threepids.sql b/synapse/storage/databases/main/schema/delta/37/user_threepids.sql
new file mode 100644
index 0000000000..cf7a90dd10
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/37/user_threepids.sql
@@ -0,0 +1,52 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Update any email addresses that were stored with mixed case into all
+ * lowercase
+ */
+
+ -- There may be "duplicate" emails (with different case) already in the table,
+ -- so we find them and move all but the most recently used account.
+ UPDATE user_threepids
+ SET medium = 'email_old'
+ WHERE medium = 'email'
+    AND address IN (
+         -- We select all the addresses that are linked to the user_id that is NOT
+         -- the most recently created.
+         SELECT u.address
+         FROM
+             user_threepids AS u,
+             -- `duplicate_addresses` is a table of all the email addresses that
+             -- appear multiple times and when the binding was created
+             (
+                 SELECT lower(u1.address) AS address, max(u1.added_at) AS max_ts
+                 FROM user_threepids AS u1
+                 INNER JOIN user_threepids AS u2 ON u1.medium = u2.medium AND lower(u1.address) = lower(u2.address) AND u1.address != u2.address
+                 WHERE u1.medium = 'email' AND u2.medium = 'email'
+                 GROUP BY lower(u1.address)
+             ) AS duplicate_addresses
+         WHERE
+             lower(u.address) = duplicate_addresses.address
+             AND u.added_at != max_ts  -- NOT the most recently created
+     );
+
+
+-- This update is now safe since we've removed the duplicate addresses.
+UPDATE user_threepids SET address = LOWER(address) WHERE medium = 'email';
+
+
+/* Add an index for the select we do on passwored reset */
+CREATE INDEX user_threepids_medium_address on user_threepids (medium, address);
diff --git a/synapse/storage/databases/main/schema/delta/38/postgres_fts_gist.sql b/synapse/storage/databases/main/schema/delta/38/postgres_fts_gist.sql
new file mode 100644
index 0000000000..515e6b8e84
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/38/postgres_fts_gist.sql
@@ -0,0 +1,19 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We no longer do this given we back it out again in schema 47
+
+-- INSERT into background_updates (update_name, progress_json)
+--     VALUES ('event_search_postgres_gist', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/39/appservice_room_list.sql b/synapse/storage/databases/main/schema/delta/39/appservice_room_list.sql
new file mode 100644
index 0000000000..74bdc49073
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/39/appservice_room_list.sql
@@ -0,0 +1,29 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE appservice_room_list(
+    appservice_id TEXT NOT NULL,
+    network_id TEXT NOT NULL,
+    room_id TEXT NOT NULL
+);
+
+-- Each appservice can have multiple published room lists associated with them,
+-- keyed of a particular network_id
+CREATE UNIQUE INDEX appservice_room_list_idx ON appservice_room_list(
+    appservice_id, network_id, room_id
+);
+
+ALTER TABLE public_room_list_stream ADD COLUMN appservice_id TEXT;
+ALTER TABLE public_room_list_stream ADD COLUMN network_id TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/39/device_federation_stream_idx.sql b/synapse/storage/databases/main/schema/delta/39/device_federation_stream_idx.sql
new file mode 100644
index 0000000000..00be801e90
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/39/device_federation_stream_idx.sql
@@ -0,0 +1,16 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE INDEX device_federation_outbox_id ON device_federation_outbox(stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/39/event_push_index.sql b/synapse/storage/databases/main/schema/delta/39/event_push_index.sql
new file mode 100644
index 0000000000..de2ad93e5c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/39/event_push_index.sql
@@ -0,0 +1,17 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('event_push_actions_highlights_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/39/federation_out_position.sql b/synapse/storage/databases/main/schema/delta/39/federation_out_position.sql
new file mode 100644
index 0000000000..5af814290b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/39/federation_out_position.sql
@@ -0,0 +1,22 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ CREATE TABLE federation_stream_position(
+     type TEXT NOT NULL,
+     stream_id INTEGER NOT NULL
+ );
+
+ INSERT INTO federation_stream_position (type, stream_id) VALUES ('federation', -1);
+ INSERT INTO federation_stream_position (type, stream_id) SELECT 'events', coalesce(max(stream_ordering), -1) FROM events;
diff --git a/synapse/storage/databases/main/schema/delta/39/membership_profile.sql b/synapse/storage/databases/main/schema/delta/39/membership_profile.sql
new file mode 100644
index 0000000000..1bf911c8ab
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/39/membership_profile.sql
@@ -0,0 +1,20 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE room_memberships ADD COLUMN display_name TEXT;
+ALTER TABLE room_memberships ADD COLUMN avatar_url TEXT;
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('room_membership_profile_update', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/40/current_state_idx.sql b/synapse/storage/databases/main/schema/delta/40/current_state_idx.sql
new file mode 100644
index 0000000000..7ffa189f39
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/40/current_state_idx.sql
@@ -0,0 +1,17 @@
+/* Copyright 2017 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('current_state_members_idx', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/40/device_inbox.sql b/synapse/storage/databases/main/schema/delta/40/device_inbox.sql
new file mode 100644
index 0000000000..b9fe1f0480
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/40/device_inbox.sql
@@ -0,0 +1,21 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- turn the pre-fill startup query into a index-only scan on postgresql.
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('device_inbox_stream_index', '{}');
+
+INSERT into background_updates (update_name, progress_json, depends_on)
+    VALUES ('device_inbox_stream_drop', '{}', 'device_inbox_stream_index');
diff --git a/synapse/storage/databases/main/schema/delta/40/device_list_streams.sql b/synapse/storage/databases/main/schema/delta/40/device_list_streams.sql
new file mode 100644
index 0000000000..dd6dcb65f1
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/40/device_list_streams.sql
@@ -0,0 +1,60 @@
+/* Copyright 2017 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Cache of remote devices.
+CREATE TABLE device_lists_remote_cache (
+    user_id TEXT NOT NULL,
+    device_id TEXT NOT NULL,
+    content TEXT NOT NULL
+);
+
+-- The last update we got for a user. Empty if we're not receiving updates for
+-- that user.
+CREATE TABLE device_lists_remote_extremeties (
+    user_id TEXT NOT NULL,
+    stream_id TEXT NOT NULL
+);
+
+-- we used to create non-unique indexes on these tables, but as of update 52 we create
+-- unique indexes concurrently:
+--
+-- CREATE INDEX device_lists_remote_cache_id ON device_lists_remote_cache(user_id, device_id);
+-- CREATE INDEX device_lists_remote_extremeties_id ON device_lists_remote_extremeties(user_id, stream_id);
+
+
+-- Stream of device lists updates. Includes both local and remotes
+CREATE TABLE device_lists_stream (
+    stream_id BIGINT NOT NULL,
+    user_id TEXT NOT NULL,
+    device_id TEXT NOT NULL
+);
+
+CREATE INDEX device_lists_stream_id ON device_lists_stream(stream_id, user_id);
+
+
+-- The stream of updates to send to other servers. We keep at least one row
+-- per user that was sent so that the prev_id for any new updates can be
+-- calculated
+CREATE TABLE device_lists_outbound_pokes (
+    destination TEXT NOT NULL,
+    stream_id BIGINT NOT NULL,
+    user_id TEXT NOT NULL,
+    device_id TEXT NOT NULL,
+    sent BOOLEAN NOT NULL,
+    ts BIGINT NOT NULL  -- So that in future we can clear out pokes to dead servers
+);
+
+CREATE INDEX device_lists_outbound_pokes_id ON device_lists_outbound_pokes(destination, stream_id);
+CREATE INDEX device_lists_outbound_pokes_user ON device_lists_outbound_pokes(destination, user_id);
diff --git a/synapse/storage/databases/main/schema/delta/40/event_push_summary.sql b/synapse/storage/databases/main/schema/delta/40/event_push_summary.sql
new file mode 100644
index 0000000000..3918f0b794
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/40/event_push_summary.sql
@@ -0,0 +1,37 @@
+/* Copyright 2017 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Aggregate of old notification counts that have been deleted out of the
+-- main event_push_actions table. This count does not include those that were
+-- highlights, as they remain in the event_push_actions table.
+CREATE TABLE event_push_summary (
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    notif_count BIGINT NOT NULL,
+    stream_ordering BIGINT NOT NULL
+);
+
+CREATE INDEX event_push_summary_user_rm ON event_push_summary(user_id, room_id);
+
+
+-- The stream ordering up to which we have aggregated the event_push_actions
+-- table into event_push_summary
+CREATE TABLE event_push_summary_stream_ordering (
+    Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE,  -- Makes sure this table only has one row.
+    stream_ordering BIGINT NOT NULL,
+    CHECK (Lock='X')
+);
+
+INSERT INTO event_push_summary_stream_ordering (stream_ordering) VALUES (0);
diff --git a/synapse/storage/databases/main/schema/delta/40/pushers.sql b/synapse/storage/databases/main/schema/delta/40/pushers.sql
new file mode 100644
index 0000000000..054a223f14
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/40/pushers.sql
@@ -0,0 +1,39 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS pushers2 (
+    id BIGINT PRIMARY KEY,
+    user_name TEXT NOT NULL,
+    access_token BIGINT DEFAULT NULL,
+    profile_tag TEXT NOT NULL,
+    kind TEXT NOT NULL,
+    app_id TEXT NOT NULL,
+    app_display_name TEXT NOT NULL,
+    device_display_name TEXT NOT NULL,
+    pushkey TEXT NOT NULL,
+    ts BIGINT NOT NULL,
+    lang TEXT,
+    data TEXT,
+    last_stream_ordering INTEGER,
+    last_success BIGINT,
+    failing_since BIGINT,
+    UNIQUE (app_id, pushkey, user_name)
+);
+
+INSERT INTO pushers2 SELECT * FROM PUSHERS;
+
+DROP TABLE PUSHERS;
+
+ALTER TABLE pushers2 RENAME TO pushers;
diff --git a/synapse/storage/databases/main/schema/delta/41/device_list_stream_idx.sql b/synapse/storage/databases/main/schema/delta/41/device_list_stream_idx.sql
new file mode 100644
index 0000000000..b7bee8b692
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/41/device_list_stream_idx.sql
@@ -0,0 +1,17 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('device_lists_stream_idx', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/41/device_outbound_index.sql b/synapse/storage/databases/main/schema/delta/41/device_outbound_index.sql
new file mode 100644
index 0000000000..62f0b9892b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/41/device_outbound_index.sql
@@ -0,0 +1,16 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE INDEX device_lists_outbound_pokes_stream ON device_lists_outbound_pokes(stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/41/event_search_event_id_idx.sql b/synapse/storage/databases/main/schema/delta/41/event_search_event_id_idx.sql
new file mode 100644
index 0000000000..5d9cfecf36
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/41/event_search_event_id_idx.sql
@@ -0,0 +1,17 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('event_search_event_id_idx', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/41/ratelimit.sql b/synapse/storage/databases/main/schema/delta/41/ratelimit.sql
new file mode 100644
index 0000000000..a194bf0238
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/41/ratelimit.sql
@@ -0,0 +1,22 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE ratelimit_override (
+    user_id TEXT NOT NULL,
+    messages_per_second BIGINT,
+    burst_count BIGINT
+);
+
+CREATE UNIQUE INDEX ratelimit_override_idx ON ratelimit_override(user_id);
diff --git a/synapse/storage/databases/main/schema/delta/42/current_state_delta.sql b/synapse/storage/databases/main/schema/delta/42/current_state_delta.sql
new file mode 100644
index 0000000000..d28851aff8
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/42/current_state_delta.sql
@@ -0,0 +1,26 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE current_state_delta_stream (
+    stream_id BIGINT NOT NULL,
+    room_id TEXT NOT NULL,
+    type TEXT NOT NULL,
+    state_key TEXT NOT NULL,
+    event_id TEXT,  -- Is null if the key was removed
+    prev_event_id TEXT  -- Is null if the key was added
+);
+
+CREATE INDEX current_state_delta_stream_idx ON current_state_delta_stream(stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/42/device_list_last_id.sql b/synapse/storage/databases/main/schema/delta/42/device_list_last_id.sql
new file mode 100644
index 0000000000..9ab8c14fa3
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/42/device_list_last_id.sql
@@ -0,0 +1,33 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+-- Table of last stream_id that we sent to destination for user_id. This is
+-- used to fill out the `prev_id` fields of outbound device list updates.
+CREATE TABLE device_lists_outbound_last_success (
+    destination TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    stream_id BIGINT NOT NULL
+);
+
+INSERT INTO device_lists_outbound_last_success
+    SELECT destination, user_id, coalesce(max(stream_id), 0) as stream_id
+        FROM device_lists_outbound_pokes
+        WHERE sent = (1 = 1)  -- sqlite doesn't have inbuilt boolean values
+        GROUP BY destination, user_id;
+
+CREATE INDEX device_lists_outbound_last_success_idx ON device_lists_outbound_last_success(
+    destination, user_id, stream_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/42/event_auth_state_only.sql b/synapse/storage/databases/main/schema/delta/42/event_auth_state_only.sql
new file mode 100644
index 0000000000..b8821ac759
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/42/event_auth_state_only.sql
@@ -0,0 +1,17 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('event_auth_state_only', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/42/user_dir.py b/synapse/storage/databases/main/schema/delta/42/user_dir.py
new file mode 100644
index 0000000000..506f326f4d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/42/user_dir.py
@@ -0,0 +1,84 @@
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from synapse.storage.engines import PostgresEngine, Sqlite3Engine
+from synapse.storage.prepare_database import get_statements
+
+logger = logging.getLogger(__name__)
+
+
+BOTH_TABLES = """
+CREATE TABLE user_directory_stream_pos (
+    Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE,  -- Makes sure this table only has one row.
+    stream_id BIGINT,
+    CHECK (Lock='X')
+);
+
+INSERT INTO user_directory_stream_pos (stream_id) VALUES (null);
+
+CREATE TABLE user_directory (
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,  -- A room_id that we know the user is joined to
+    display_name TEXT,
+    avatar_url TEXT
+);
+
+CREATE INDEX user_directory_room_idx ON user_directory(room_id);
+CREATE UNIQUE INDEX user_directory_user_idx ON user_directory(user_id);
+
+CREATE TABLE users_in_pubic_room (
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL  -- A room_id that we know is public
+);
+
+CREATE INDEX users_in_pubic_room_room_idx ON users_in_pubic_room(room_id);
+CREATE UNIQUE INDEX users_in_pubic_room_user_idx ON users_in_pubic_room(user_id);
+"""
+
+
+POSTGRES_TABLE = """
+CREATE TABLE user_directory_search (
+    user_id TEXT NOT NULL,
+    vector tsvector
+);
+
+CREATE INDEX user_directory_search_fts_idx ON user_directory_search USING gin(vector);
+CREATE UNIQUE INDEX user_directory_search_user_idx ON user_directory_search(user_id);
+"""
+
+
+SQLITE_TABLE = """
+CREATE VIRTUAL TABLE user_directory_search
+    USING fts4 ( user_id, value );
+"""
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    for statement in get_statements(BOTH_TABLES.splitlines()):
+        cur.execute(statement)
+
+    if isinstance(database_engine, PostgresEngine):
+        for statement in get_statements(POSTGRES_TABLE.splitlines()):
+            cur.execute(statement)
+    elif isinstance(database_engine, Sqlite3Engine):
+        for statement in get_statements(SQLITE_TABLE.splitlines()):
+            cur.execute(statement)
+    else:
+        raise Exception("Unrecognized database engine")
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/43/blocked_rooms.sql b/synapse/storage/databases/main/schema/delta/43/blocked_rooms.sql
new file mode 100644
index 0000000000..0e3cd143ff
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/43/blocked_rooms.sql
@@ -0,0 +1,21 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE blocked_rooms (
+    room_id TEXT NOT NULL,
+    user_id TEXT NOT NULL  -- Admin who blocked the room
+);
+
+CREATE UNIQUE INDEX blocked_rooms_idx ON blocked_rooms(room_id);
diff --git a/synapse/storage/databases/main/schema/delta/43/quarantine_media.sql b/synapse/storage/databases/main/schema/delta/43/quarantine_media.sql
new file mode 100644
index 0000000000..630907ec4f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/43/quarantine_media.sql
@@ -0,0 +1,17 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE local_media_repository ADD COLUMN quarantined_by TEXT;
+ALTER TABLE remote_media_cache ADD COLUMN quarantined_by TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/43/url_cache.sql b/synapse/storage/databases/main/schema/delta/43/url_cache.sql
new file mode 100644
index 0000000000..45ebe020da
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/43/url_cache.sql
@@ -0,0 +1,16 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE local_media_repository ADD COLUMN url_cache TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/43/user_share.sql b/synapse/storage/databases/main/schema/delta/43/user_share.sql
new file mode 100644
index 0000000000..ee7062abe4
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/43/user_share.sql
@@ -0,0 +1,33 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Table keeping track of who shares a room with who. We only keep track
+-- of this for local users, so `user_id` is local users only (but we do keep track
+-- of which remote users share a room)
+CREATE TABLE users_who_share_rooms (
+    user_id TEXT NOT NULL,
+    other_user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    share_private BOOLEAN NOT NULL  -- is the shared room private? i.e. they share a private room
+);
+
+
+CREATE UNIQUE INDEX users_who_share_rooms_u_idx ON users_who_share_rooms(user_id, other_user_id);
+CREATE INDEX users_who_share_rooms_r_idx ON users_who_share_rooms(room_id);
+CREATE INDEX users_who_share_rooms_o_idx ON users_who_share_rooms(other_user_id);
+
+
+-- Make sure that we populate the table initially
+UPDATE user_directory_stream_pos SET stream_id = NULL;
diff --git a/synapse/storage/databases/main/schema/delta/44/expire_url_cache.sql b/synapse/storage/databases/main/schema/delta/44/expire_url_cache.sql
new file mode 100644
index 0000000000..b12f9b2ebf
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/44/expire_url_cache.sql
@@ -0,0 +1,41 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- this didn't work on SQLite 3.7 (because of lack of partial indexes), so was
+-- removed and replaced with 46/local_media_repository_url_idx.sql.
+--
+-- CREATE INDEX local_media_repository_url_idx ON local_media_repository(created_ts) WHERE url_cache IS NOT NULL;
+
+-- we need to change `expires` to `expires_ts` so that we can index on it. SQLite doesn't support
+-- indices on expressions until 3.9.
+CREATE TABLE local_media_repository_url_cache_new(
+    url TEXT,
+    response_code INTEGER,
+    etag TEXT,
+    expires_ts BIGINT,
+    og TEXT,
+    media_id TEXT,
+    download_ts BIGINT
+);
+
+INSERT INTO local_media_repository_url_cache_new
+    SELECT url, response_code, etag, expires + download_ts, og, media_id, download_ts FROM local_media_repository_url_cache;
+
+DROP TABLE local_media_repository_url_cache;
+ALTER TABLE local_media_repository_url_cache_new RENAME TO local_media_repository_url_cache;
+
+CREATE INDEX local_media_repository_url_cache_expires_idx ON local_media_repository_url_cache(expires_ts);
+CREATE INDEX local_media_repository_url_cache_by_url_download_ts ON local_media_repository_url_cache(url, download_ts);
+CREATE INDEX local_media_repository_url_cache_media_idx ON local_media_repository_url_cache(media_id);
diff --git a/synapse/storage/databases/main/schema/delta/45/group_server.sql b/synapse/storage/databases/main/schema/delta/45/group_server.sql
new file mode 100644
index 0000000000..b2333848a0
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/45/group_server.sql
@@ -0,0 +1,167 @@
+/* Copyright 2017 Vector Creations Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE groups (
+    group_id TEXT NOT NULL,
+    name TEXT,  -- the display name of the room
+    avatar_url TEXT,
+    short_description TEXT,
+    long_description TEXT
+);
+
+CREATE UNIQUE INDEX groups_idx ON groups(group_id);
+
+
+-- list of users the group server thinks are joined
+CREATE TABLE group_users (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    is_admin BOOLEAN NOT NULL,
+    is_public BOOLEAN NOT NULL  -- whether the users membership can be seen by everyone
+);
+
+
+CREATE INDEX groups_users_g_idx ON group_users(group_id, user_id);
+CREATE INDEX groups_users_u_idx ON group_users(user_id);
+
+-- list of users the group server thinks are invited
+CREATE TABLE group_invites (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL
+);
+
+CREATE INDEX groups_invites_g_idx ON group_invites(group_id, user_id);
+CREATE INDEX groups_invites_u_idx ON group_invites(user_id);
+
+
+CREATE TABLE group_rooms (
+    group_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    is_public BOOLEAN NOT NULL  -- whether the room can be seen by everyone
+);
+
+CREATE UNIQUE INDEX groups_rooms_g_idx ON group_rooms(group_id, room_id);
+CREATE INDEX groups_rooms_r_idx ON group_rooms(room_id);
+
+
+-- Rooms to include in the summary
+CREATE TABLE group_summary_rooms (
+    group_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    category_id TEXT NOT NULL,
+    room_order BIGINT NOT NULL,
+    is_public BOOLEAN NOT NULL, -- whether the room should be show to everyone
+    UNIQUE (group_id, category_id, room_id, room_order),
+    CHECK (room_order > 0)
+);
+
+CREATE UNIQUE INDEX group_summary_rooms_g_idx ON group_summary_rooms(group_id, room_id, category_id);
+
+
+-- Categories to include in the summary
+CREATE TABLE group_summary_room_categories (
+    group_id TEXT NOT NULL,
+    category_id TEXT NOT NULL,
+    cat_order BIGINT NOT NULL,
+    UNIQUE (group_id, category_id, cat_order),
+    CHECK (cat_order > 0)
+);
+
+-- The categories in the group
+CREATE TABLE group_room_categories (
+    group_id TEXT NOT NULL,
+    category_id TEXT NOT NULL,
+    profile TEXT NOT NULL,
+    is_public BOOLEAN NOT NULL, -- whether the category should be show to everyone
+    UNIQUE (group_id, category_id)
+);
+
+-- The users to include in the group summary
+CREATE TABLE group_summary_users (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    role_id TEXT NOT NULL,
+    user_order BIGINT NOT NULL,
+    is_public BOOLEAN NOT NULL  -- whether the user should be show to everyone
+);
+
+CREATE INDEX group_summary_users_g_idx ON group_summary_users(group_id);
+
+-- The roles to include in the group summary
+CREATE TABLE group_summary_roles (
+    group_id TEXT NOT NULL,
+    role_id TEXT NOT NULL,
+    role_order BIGINT NOT NULL,
+    UNIQUE (group_id, role_id, role_order),
+    CHECK (role_order > 0)
+);
+
+
+-- The roles in a groups
+CREATE TABLE group_roles (
+    group_id TEXT NOT NULL,
+    role_id TEXT NOT NULL,
+    profile TEXT NOT NULL,
+    is_public BOOLEAN NOT NULL,  -- whether the role should be show to everyone
+    UNIQUE (group_id, role_id)
+);
+
+
+-- List of  attestations we've given out and need to renew
+CREATE TABLE group_attestations_renewals (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    valid_until_ms BIGINT NOT NULL
+);
+
+CREATE INDEX group_attestations_renewals_g_idx ON group_attestations_renewals(group_id, user_id);
+CREATE INDEX group_attestations_renewals_u_idx ON group_attestations_renewals(user_id);
+CREATE INDEX group_attestations_renewals_v_idx ON group_attestations_renewals(valid_until_ms);
+
+
+-- List of attestations we've received from remotes and are interested in.
+CREATE TABLE group_attestations_remote (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    valid_until_ms BIGINT NOT NULL,
+    attestation_json TEXT NOT NULL
+);
+
+CREATE INDEX group_attestations_remote_g_idx ON group_attestations_remote(group_id, user_id);
+CREATE INDEX group_attestations_remote_u_idx ON group_attestations_remote(user_id);
+CREATE INDEX group_attestations_remote_v_idx ON group_attestations_remote(valid_until_ms);
+
+
+-- The group membership for the HS's users
+CREATE TABLE local_group_membership (
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    is_admin BOOLEAN NOT NULL,
+    membership TEXT NOT NULL,
+    is_publicised BOOLEAN NOT NULL,  -- if the user is publicising their membership
+    content TEXT NOT NULL
+);
+
+CREATE INDEX local_group_membership_u_idx ON local_group_membership(user_id, group_id);
+CREATE INDEX local_group_membership_g_idx ON local_group_membership(group_id);
+
+
+CREATE TABLE local_group_updates (
+    stream_id BIGINT NOT NULL,
+    group_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    type TEXT NOT NULL,
+    content TEXT NOT NULL
+);
diff --git a/synapse/storage/databases/main/schema/delta/45/profile_cache.sql b/synapse/storage/databases/main/schema/delta/45/profile_cache.sql
new file mode 100644
index 0000000000..e5ddc84df0
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/45/profile_cache.sql
@@ -0,0 +1,28 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+-- A subset of remote users whose profiles we have cached.
+-- Whether a user is in this table or not is defined by the storage function
+-- `is_subscribed_remote_profile_for_user`
+CREATE TABLE remote_profile_cache (
+    user_id TEXT NOT NULL,
+    displayname TEXT,
+    avatar_url TEXT,
+    last_check BIGINT NOT NULL
+);
+
+CREATE UNIQUE INDEX remote_profile_cache_user_id ON remote_profile_cache(user_id);
+CREATE INDEX remote_profile_cache_time ON remote_profile_cache(last_check);
diff --git a/synapse/storage/databases/main/schema/delta/46/drop_refresh_tokens.sql b/synapse/storage/databases/main/schema/delta/46/drop_refresh_tokens.sql
new file mode 100644
index 0000000000..68c48a89a9
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/46/drop_refresh_tokens.sql
@@ -0,0 +1,17 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* we no longer use (or create) the refresh_tokens table */
+DROP TABLE IF EXISTS refresh_tokens;
diff --git a/synapse/storage/databases/main/schema/delta/46/drop_unique_deleted_pushers.sql b/synapse/storage/databases/main/schema/delta/46/drop_unique_deleted_pushers.sql
new file mode 100644
index 0000000000..bb307889c1
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/46/drop_unique_deleted_pushers.sql
@@ -0,0 +1,35 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- drop the unique constraint on deleted_pushers so that we can just insert
+-- into it rather than upserting.
+
+CREATE TABLE deleted_pushers2 (
+    stream_id BIGINT NOT NULL,
+    app_id TEXT NOT NULL,
+    pushkey TEXT NOT NULL,
+    user_id TEXT NOT NULL
+);
+
+INSERT INTO deleted_pushers2 (stream_id, app_id, pushkey, user_id)
+    SELECT stream_id, app_id, pushkey, user_id from deleted_pushers;
+
+DROP TABLE deleted_pushers;
+ALTER TABLE deleted_pushers2 RENAME TO deleted_pushers;
+
+-- create the index after doing the inserts because that's more efficient.
+-- it also means we can give it the same name as the old one without renaming.
+CREATE INDEX deleted_pushers_stream_id ON deleted_pushers (stream_id);
+
diff --git a/synapse/storage/databases/main/schema/delta/46/group_server.sql b/synapse/storage/databases/main/schema/delta/46/group_server.sql
new file mode 100644
index 0000000000..097679bc9a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/46/group_server.sql
@@ -0,0 +1,32 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE groups_new (
+    group_id TEXT NOT NULL,
+    name TEXT,  -- the display name of the room
+    avatar_url TEXT,
+    short_description TEXT,
+    long_description TEXT,
+    is_public BOOL NOT NULL -- whether non-members can access group APIs
+);
+
+-- NB: awful hack to get the default to be true on postgres and 1 on sqlite
+INSERT INTO groups_new
+    SELECT group_id, name, avatar_url, short_description, long_description, (1=1) FROM groups;
+
+DROP TABLE groups;
+ALTER TABLE groups_new RENAME TO groups;
+
+CREATE UNIQUE INDEX groups_idx ON groups(group_id);
diff --git a/synapse/storage/databases/main/schema/delta/46/local_media_repository_url_idx.sql b/synapse/storage/databases/main/schema/delta/46/local_media_repository_url_idx.sql
new file mode 100644
index 0000000000..bbfc7f5d1a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/46/local_media_repository_url_idx.sql
@@ -0,0 +1,24 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- register a background update which will recreate the
+-- local_media_repository_url_idx index.
+--
+-- We do this as a bg update not because it is a particularly onerous
+-- operation, but because we'd like it to be a partial index if possible, and
+-- the background_index_update code will understand whether we are on
+-- postgres or sqlite and behave accordingly.
+INSERT INTO background_updates (update_name, progress_json) VALUES
+    ('local_media_repository_url_idx', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/46/user_dir_null_room_ids.sql b/synapse/storage/databases/main/schema/delta/46/user_dir_null_room_ids.sql
new file mode 100644
index 0000000000..cb0d5a2576
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/46/user_dir_null_room_ids.sql
@@ -0,0 +1,35 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- change the user_directory table to also cover global local user profiles
+-- rather than just profiles within specific rooms.
+
+CREATE TABLE user_directory2 (
+    user_id TEXT NOT NULL,
+    room_id TEXT,
+    display_name TEXT,
+    avatar_url TEXT
+);
+
+INSERT INTO user_directory2(user_id, room_id, display_name, avatar_url)
+    SELECT user_id, room_id, display_name, avatar_url from user_directory;
+
+DROP TABLE user_directory;
+ALTER TABLE user_directory2 RENAME TO user_directory;
+
+-- create indexes after doing the inserts because that's more efficient.
+-- it also means we can give it the same name as the old one without renaming.
+CREATE INDEX user_directory_room_idx ON user_directory(room_id);
+CREATE UNIQUE INDEX user_directory_user_idx ON user_directory(user_id);
diff --git a/synapse/storage/databases/main/schema/delta/46/user_dir_typos.sql b/synapse/storage/databases/main/schema/delta/46/user_dir_typos.sql
new file mode 100644
index 0000000000..d9505f8da1
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/46/user_dir_typos.sql
@@ -0,0 +1,24 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- this is just embarassing :|
+ALTER TABLE users_in_pubic_room RENAME TO users_in_public_rooms;
+
+-- this is only 300K rows on matrix.org and takes ~3s to generate the index,
+-- so is hopefully not going to block anyone else for that long...
+CREATE INDEX users_in_public_rooms_room_idx ON users_in_public_rooms(room_id);
+CREATE UNIQUE INDEX users_in_public_rooms_user_idx ON users_in_public_rooms(user_id);
+DROP INDEX users_in_pubic_room_room_idx;
+DROP INDEX users_in_pubic_room_user_idx;
diff --git a/synapse/storage/databases/main/schema/delta/47/last_access_media.sql b/synapse/storage/databases/main/schema/delta/47/last_access_media.sql
new file mode 100644
index 0000000000..f505fb22b5
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/47/last_access_media.sql
@@ -0,0 +1,16 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE local_media_repository ADD COLUMN last_access_ts BIGINT;
diff --git a/synapse/storage/databases/main/schema/delta/47/postgres_fts_gin.sql b/synapse/storage/databases/main/schema/delta/47/postgres_fts_gin.sql
new file mode 100644
index 0000000000..31d7a817eb
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/47/postgres_fts_gin.sql
@@ -0,0 +1,17 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('event_search_postgres_gin', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/47/push_actions_staging.sql b/synapse/storage/databases/main/schema/delta/47/push_actions_staging.sql
new file mode 100644
index 0000000000..edccf4a96f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/47/push_actions_staging.sql
@@ -0,0 +1,28 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Temporary staging area for push actions that have been calculated for an
+-- event, but the event hasn't yet been persisted.
+-- When the event is persisted the rows are moved over to the
+-- event_push_actions table.
+CREATE TABLE event_push_actions_staging (
+    event_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    actions TEXT NOT NULL,
+    notif SMALLINT NOT NULL,
+    highlight SMALLINT NOT NULL
+);
+
+CREATE INDEX event_push_actions_staging_id ON event_push_actions_staging(event_id);
diff --git a/synapse/storage/databases/main/schema/delta/48/add_user_consent.sql b/synapse/storage/databases/main/schema/delta/48/add_user_consent.sql
new file mode 100644
index 0000000000..5237491506
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/48/add_user_consent.sql
@@ -0,0 +1,18 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* record the version of the privacy policy the user has consented to
+ */
+ALTER TABLE users ADD COLUMN consent_version TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/48/add_user_ips_last_seen_index.sql b/synapse/storage/databases/main/schema/delta/48/add_user_ips_last_seen_index.sql
new file mode 100644
index 0000000000..9248b0b24a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/48/add_user_ips_last_seen_index.sql
@@ -0,0 +1,17 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('user_ips_last_seen_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/48/deactivated_users.sql b/synapse/storage/databases/main/schema/delta/48/deactivated_users.sql
new file mode 100644
index 0000000000..e9013a6969
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/48/deactivated_users.sql
@@ -0,0 +1,25 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Store any accounts that have been requested to be deactivated.
+ * We part the account from all the rooms its in when its
+ * deactivated. This can take some time and synapse may be restarted
+ * before it completes, so store the user IDs here until the process
+ * is complete.
+ */
+CREATE TABLE users_pending_deactivation (
+    user_id TEXT NOT NULL
+);
diff --git a/synapse/storage/databases/main/schema/delta/48/group_unique_indexes.py b/synapse/storage/databases/main/schema/delta/48/group_unique_indexes.py
new file mode 100644
index 0000000000..49f5f2c003
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/48/group_unique_indexes.py
@@ -0,0 +1,63 @@
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from synapse.storage.engines import PostgresEngine
+from synapse.storage.prepare_database import get_statements
+
+FIX_INDEXES = """
+-- rebuild indexes as uniques
+DROP INDEX groups_invites_g_idx;
+CREATE UNIQUE INDEX group_invites_g_idx ON group_invites(group_id, user_id);
+DROP INDEX groups_users_g_idx;
+CREATE UNIQUE INDEX group_users_g_idx ON group_users(group_id, user_id);
+
+-- rename other indexes to actually match their table names..
+DROP INDEX groups_users_u_idx;
+CREATE INDEX group_users_u_idx ON group_users(user_id);
+DROP INDEX groups_invites_u_idx;
+CREATE INDEX group_invites_u_idx ON group_invites(user_id);
+DROP INDEX groups_rooms_g_idx;
+CREATE UNIQUE INDEX group_rooms_g_idx ON group_rooms(group_id, room_id);
+DROP INDEX groups_rooms_r_idx;
+CREATE INDEX group_rooms_r_idx ON group_rooms(room_id);
+"""
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    rowid = "ctid" if isinstance(database_engine, PostgresEngine) else "rowid"
+
+    # remove duplicates from group_users & group_invites tables
+    cur.execute(
+        """
+        DELETE FROM group_users WHERE %s NOT IN (
+           SELECT min(%s) FROM group_users GROUP BY group_id, user_id
+        );
+    """
+        % (rowid, rowid)
+    )
+    cur.execute(
+        """
+        DELETE FROM group_invites WHERE %s NOT IN (
+           SELECT min(%s) FROM group_invites GROUP BY group_id, user_id
+        );
+    """
+        % (rowid, rowid)
+    )
+
+    for statement in get_statements(FIX_INDEXES.splitlines()):
+        cur.execute(statement)
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/48/groups_joinable.sql b/synapse/storage/databases/main/schema/delta/48/groups_joinable.sql
new file mode 100644
index 0000000000..ce26eaf0c9
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/48/groups_joinable.sql
@@ -0,0 +1,22 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* 
+ * This isn't a real ENUM because sqlite doesn't support it
+ * and we use a default of NULL for inserted rows and interpret
+ * NULL at the python store level as necessary so that existing
+ * rows are given the correct default policy.
+ */
+ALTER TABLE groups ADD COLUMN join_policy TEXT NOT NULL DEFAULT 'invite';
diff --git a/synapse/storage/databases/main/schema/delta/49/add_user_consent_server_notice_sent.sql b/synapse/storage/databases/main/schema/delta/49/add_user_consent_server_notice_sent.sql
new file mode 100644
index 0000000000..14dcf18d73
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/49/add_user_consent_server_notice_sent.sql
@@ -0,0 +1,20 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* record whether we have sent a server notice about consenting to the
+ * privacy policy. Specifically records the version of the policy we sent
+ * a message about.
+ */
+ALTER TABLE users ADD COLUMN consent_server_notice_sent TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/49/add_user_daily_visits.sql b/synapse/storage/databases/main/schema/delta/49/add_user_daily_visits.sql
new file mode 100644
index 0000000000..3dd478196f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/49/add_user_daily_visits.sql
@@ -0,0 +1,21 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE user_daily_visits ( user_id TEXT NOT NULL,
+                                 device_id TEXT,
+                                 timestamp BIGINT NOT NULL );
+CREATE INDEX user_daily_visits_uts_idx ON user_daily_visits(user_id, timestamp);
+CREATE INDEX user_daily_visits_ts_idx ON user_daily_visits(timestamp);
diff --git a/synapse/storage/databases/main/schema/delta/49/add_user_ips_last_seen_only_index.sql b/synapse/storage/databases/main/schema/delta/49/add_user_ips_last_seen_only_index.sql
new file mode 100644
index 0000000000..3a4ed59b5b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/49/add_user_ips_last_seen_only_index.sql
@@ -0,0 +1,17 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('user_ips_last_seen_only_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/50/add_creation_ts_users_index.sql b/synapse/storage/databases/main/schema/delta/50/add_creation_ts_users_index.sql
new file mode 100644
index 0000000000..c93ae47532
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/50/add_creation_ts_users_index.sql
@@ -0,0 +1,19 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('users_creation_ts', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/50/erasure_store.sql b/synapse/storage/databases/main/schema/delta/50/erasure_store.sql
new file mode 100644
index 0000000000..5d8641a9ab
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/50/erasure_store.sql
@@ -0,0 +1,21 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- a table of users who have requested that their details be erased
+CREATE TABLE erased_users (
+    user_id TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX erased_users_user ON erased_users(user_id);
diff --git a/synapse/storage/databases/main/schema/delta/50/make_event_content_nullable.py b/synapse/storage/databases/main/schema/delta/50/make_event_content_nullable.py
new file mode 100644
index 0000000000..b1684a8441
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/50/make_event_content_nullable.py
@@ -0,0 +1,96 @@
+# -*- coding: utf-8 -*-
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+We want to stop populating 'event.content', so we need to make it nullable.
+
+If this has to be rolled back, then the following should populate the missing data:
+
+Postgres:
+
+    UPDATE events SET content=(ej.json::json)->'content' FROM event_json ej
+    WHERE ej.event_id = events.event_id AND
+        stream_ordering < (
+            SELECT stream_ordering FROM events WHERE content IS NOT NULL
+            ORDER BY stream_ordering LIMIT 1
+        );
+
+    UPDATE events SET content=(ej.json::json)->'content' FROM event_json ej
+    WHERE ej.event_id = events.event_id AND
+        stream_ordering > (
+            SELECT stream_ordering FROM events WHERE content IS NOT NULL
+            ORDER BY stream_ordering DESC LIMIT 1
+        );
+
+SQLite:
+
+    UPDATE events SET content=(
+        SELECT json_extract(json,'$.content') FROM event_json ej
+        WHERE ej.event_id = events.event_id
+    )
+    WHERE
+        stream_ordering < (
+            SELECT stream_ordering FROM events WHERE content IS NOT NULL
+            ORDER BY stream_ordering LIMIT 1
+        )
+        OR stream_ordering > (
+            SELECT stream_ordering FROM events WHERE content IS NOT NULL
+            ORDER BY stream_ordering DESC LIMIT 1
+        );
+
+"""
+
+import logging
+
+from synapse.storage.engines import PostgresEngine
+
+logger = logging.getLogger(__name__)
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    pass
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    if isinstance(database_engine, PostgresEngine):
+        cur.execute(
+            """
+            ALTER TABLE events ALTER COLUMN content DROP NOT NULL;
+        """
+        )
+        return
+
+    # sqlite is an arse about this. ref: https://www.sqlite.org/lang_altertable.html
+
+    cur.execute(
+        "SELECT sql FROM sqlite_master WHERE tbl_name='events' AND type='table'"
+    )
+    (oldsql,) = cur.fetchone()
+
+    sql = oldsql.replace("content TEXT NOT NULL", "content TEXT")
+    if sql == oldsql:
+        raise Exception("Couldn't find null constraint to drop in %s" % oldsql)
+
+    logger.info("Replacing definition of 'events' with: %s", sql)
+
+    cur.execute("PRAGMA schema_version")
+    (oldver,) = cur.fetchone()
+    cur.execute("PRAGMA writable_schema=ON")
+    cur.execute(
+        "UPDATE sqlite_master SET sql=? WHERE tbl_name='events' AND type='table'",
+        (sql,),
+    )
+    cur.execute("PRAGMA schema_version=%i" % (oldver + 1,))
+    cur.execute("PRAGMA writable_schema=OFF")
diff --git a/synapse/storage/databases/main/schema/delta/51/e2e_room_keys.sql b/synapse/storage/databases/main/schema/delta/51/e2e_room_keys.sql
new file mode 100644
index 0000000000..c0e66a697d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/51/e2e_room_keys.sql
@@ -0,0 +1,39 @@
+/* Copyright 2017 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- users' optionally backed up encrypted e2e sessions
+CREATE TABLE e2e_room_keys (
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    session_id TEXT NOT NULL,
+    version TEXT NOT NULL,
+    first_message_index INT,
+    forwarded_count INT,
+    is_verified BOOLEAN,
+    session_data TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX e2e_room_keys_idx ON e2e_room_keys(user_id, room_id, session_id);
+
+-- the metadata for each generation of encrypted e2e session backups
+CREATE TABLE e2e_room_keys_versions (
+    user_id TEXT NOT NULL,
+    version TEXT NOT NULL,
+    algorithm TEXT NOT NULL,
+    auth_data TEXT NOT NULL,
+    deleted SMALLINT DEFAULT 0 NOT NULL
+);
+
+CREATE UNIQUE INDEX e2e_room_keys_versions_idx ON e2e_room_keys_versions(user_id, version);
diff --git a/synapse/storage/databases/main/schema/delta/51/monthly_active_users.sql b/synapse/storage/databases/main/schema/delta/51/monthly_active_users.sql
new file mode 100644
index 0000000000..c9d537d5a3
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/51/monthly_active_users.sql
@@ -0,0 +1,27 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- a table of monthly active users, for use where blocking based on mau limits
+CREATE TABLE monthly_active_users (
+    user_id TEXT NOT NULL,
+    -- Last time we saw the user. Not guaranteed to be accurate due to rate limiting
+    -- on updates, Granularity of updates governed by
+    -- synapse.storage.monthly_active_users.LAST_SEEN_GRANULARITY
+    -- Measured in ms since epoch.
+    timestamp BIGINT NOT NULL
+);
+
+CREATE UNIQUE INDEX monthly_active_users_users ON monthly_active_users(user_id);
+CREATE INDEX monthly_active_users_time_stamp ON monthly_active_users(timestamp);
diff --git a/synapse/storage/databases/main/schema/delta/52/add_event_to_state_group_index.sql b/synapse/storage/databases/main/schema/delta/52/add_event_to_state_group_index.sql
new file mode 100644
index 0000000000..91e03d13e1
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/52/add_event_to_state_group_index.sql
@@ -0,0 +1,19 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- This is needed to efficiently check for unreferenced state groups during
+-- purge. Added events_to_state_group(state_group) index
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('event_to_state_groups_sg_index', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/52/device_list_streams_unique_idx.sql b/synapse/storage/databases/main/schema/delta/52/device_list_streams_unique_idx.sql
new file mode 100644
index 0000000000..bfa49e6f92
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/52/device_list_streams_unique_idx.sql
@@ -0,0 +1,36 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- register a background update which will create a unique index on
+-- device_lists_remote_cache
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('device_lists_remote_cache_unique_idx', '{}');
+
+-- and one on device_lists_remote_extremeties
+INSERT into background_updates (update_name, progress_json, depends_on)
+    VALUES (
+        'device_lists_remote_extremeties_unique_idx', '{}',
+
+        -- doesn't really depend on this, but we need to make sure both happen
+        -- before we drop the old indexes.
+        'device_lists_remote_cache_unique_idx'
+    );
+
+-- once they complete, we can drop the old indexes.
+INSERT into background_updates (update_name, progress_json, depends_on)
+    VALUES (
+        'drop_device_list_streams_non_unique_indexes', '{}',
+        'device_lists_remote_extremeties_unique_idx'
+    );
diff --git a/synapse/storage/databases/main/schema/delta/52/e2e_room_keys.sql b/synapse/storage/databases/main/schema/delta/52/e2e_room_keys.sql
new file mode 100644
index 0000000000..db687cccae
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/52/e2e_room_keys.sql
@@ -0,0 +1,53 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Change version column to an integer so we can do MAX() sensibly
+ */
+CREATE TABLE e2e_room_keys_versions_new (
+    user_id TEXT NOT NULL,
+    version BIGINT NOT NULL,
+    algorithm TEXT NOT NULL,
+    auth_data TEXT NOT NULL,
+    deleted SMALLINT DEFAULT 0 NOT NULL
+);
+
+INSERT INTO e2e_room_keys_versions_new
+    SELECT user_id, CAST(version as BIGINT), algorithm, auth_data, deleted FROM e2e_room_keys_versions;
+
+DROP TABLE e2e_room_keys_versions;
+ALTER TABLE e2e_room_keys_versions_new RENAME TO e2e_room_keys_versions;
+
+CREATE UNIQUE INDEX e2e_room_keys_versions_idx ON e2e_room_keys_versions(user_id, version);
+
+/* Change e2e_rooms_keys to match
+ */
+CREATE TABLE e2e_room_keys_new (
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    session_id TEXT NOT NULL,
+    version BIGINT NOT NULL,
+    first_message_index INT,
+    forwarded_count INT,
+    is_verified BOOLEAN,
+    session_data TEXT NOT NULL
+);
+
+INSERT INTO e2e_room_keys_new
+    SELECT user_id, room_id, session_id, CAST(version as BIGINT), first_message_index, forwarded_count, is_verified, session_data FROM e2e_room_keys;
+
+DROP TABLE e2e_room_keys;
+ALTER TABLE e2e_room_keys_new RENAME TO e2e_room_keys;
+
+CREATE UNIQUE INDEX e2e_room_keys_idx ON e2e_room_keys(user_id, room_id, session_id);
diff --git a/synapse/storage/databases/main/schema/delta/53/add_user_type_to_users.sql b/synapse/storage/databases/main/schema/delta/53/add_user_type_to_users.sql
new file mode 100644
index 0000000000..88ec2f83e5
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/add_user_type_to_users.sql
@@ -0,0 +1,19 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* The type of the user: NULL for a regular user, or one of the constants in 
+ * synapse.api.constants.UserTypes
+ */
+ALTER TABLE users ADD COLUMN user_type TEXT DEFAULT NULL;
diff --git a/synapse/storage/databases/main/schema/delta/53/drop_sent_transactions.sql b/synapse/storage/databases/main/schema/delta/53/drop_sent_transactions.sql
new file mode 100644
index 0000000000..e372f5a44a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/drop_sent_transactions.sql
@@ -0,0 +1,16 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+DROP TABLE IF EXISTS sent_transactions;
diff --git a/synapse/storage/databases/main/schema/delta/53/event_format_version.sql b/synapse/storage/databases/main/schema/delta/53/event_format_version.sql
new file mode 100644
index 0000000000..1d977c2834
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/event_format_version.sql
@@ -0,0 +1,16 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE event_json ADD COLUMN format_version INTEGER;
diff --git a/synapse/storage/databases/main/schema/delta/53/user_dir_populate.sql b/synapse/storage/databases/main/schema/delta/53/user_dir_populate.sql
new file mode 100644
index 0000000000..ffcc896b58
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/user_dir_populate.sql
@@ -0,0 +1,30 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Set up staging tables
+INSERT INTO background_updates (update_name, progress_json) VALUES
+    ('populate_user_directory_createtables', '{}');
+
+-- Run through each room and update the user directory according to who is in it
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+    ('populate_user_directory_process_rooms', '{}', 'populate_user_directory_createtables');
+
+-- Insert all users, if search_all_users is on
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+    ('populate_user_directory_process_users', '{}', 'populate_user_directory_process_rooms');
+
+-- Clean up staging tables
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+    ('populate_user_directory_cleanup', '{}', 'populate_user_directory_process_users');
diff --git a/synapse/storage/databases/main/schema/delta/53/user_ips_index.sql b/synapse/storage/databases/main/schema/delta/53/user_ips_index.sql
new file mode 100644
index 0000000000..b812c5794f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/user_ips_index.sql
@@ -0,0 +1,30 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ -- analyze user_ips, to help ensure the correct indices are used
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('user_ips_analyze', '{}');
+
+-- delete duplicates
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+  ('user_ips_remove_dupes', '{}', 'user_ips_analyze');
+
+-- add a new unique index to user_ips table
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+  ('user_ips_device_unique_index', '{}', 'user_ips_remove_dupes');
+
+-- drop the old original index
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+  ('user_ips_drop_nonunique_index', '{}', 'user_ips_device_unique_index');
diff --git a/synapse/storage/databases/main/schema/delta/53/user_share.sql b/synapse/storage/databases/main/schema/delta/53/user_share.sql
new file mode 100644
index 0000000000..5831b1a6f8
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/user_share.sql
@@ -0,0 +1,44 @@
+/* Copyright 2017 Vector Creations Ltd, 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Old disused version of the tables below.
+DROP TABLE IF EXISTS users_who_share_rooms;
+
+-- Tables keeping track of what users share rooms. This is a map of local users
+-- to local or remote users, per room. Remote users cannot be in the user_id
+-- column, only the other_user_id column. There are two tables, one for public
+-- rooms and those for private rooms.
+CREATE TABLE IF NOT EXISTS users_who_share_public_rooms (
+    user_id TEXT NOT NULL,
+    other_user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS users_who_share_private_rooms (
+    user_id TEXT NOT NULL,
+    other_user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX users_who_share_public_rooms_u_idx ON users_who_share_public_rooms(user_id, other_user_id, room_id);
+CREATE INDEX users_who_share_public_rooms_r_idx ON users_who_share_public_rooms(room_id);
+CREATE INDEX users_who_share_public_rooms_o_idx ON users_who_share_public_rooms(other_user_id);
+
+CREATE UNIQUE INDEX users_who_share_private_rooms_u_idx ON users_who_share_private_rooms(user_id, other_user_id, room_id);
+CREATE INDEX users_who_share_private_rooms_r_idx ON users_who_share_private_rooms(room_id);
+CREATE INDEX users_who_share_private_rooms_o_idx ON users_who_share_private_rooms(other_user_id);
+
+-- Make sure that we populate the tables initially by resetting the stream ID
+UPDATE user_directory_stream_pos SET stream_id = NULL;
diff --git a/synapse/storage/databases/main/schema/delta/53/user_threepid_id.sql b/synapse/storage/databases/main/schema/delta/53/user_threepid_id.sql
new file mode 100644
index 0000000000..80c2c573b6
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/user_threepid_id.sql
@@ -0,0 +1,29 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Tracks which identity server a user bound their threepid via.
+CREATE TABLE user_threepid_id_server (
+    user_id TEXT NOT NULL,
+    medium TEXT NOT NULL,
+    address TEXT NOT NULL,
+    id_server TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX user_threepid_id_server_idx ON user_threepid_id_server(
+    user_id, medium, address, id_server
+);
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('user_threepids_grandfather', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/53/users_in_public_rooms.sql b/synapse/storage/databases/main/schema/delta/53/users_in_public_rooms.sql
new file mode 100644
index 0000000000..f7827ca6d2
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/53/users_in_public_rooms.sql
@@ -0,0 +1,28 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We don't need the old version of this table.
+DROP TABLE IF EXISTS users_in_public_rooms;
+
+-- Old version of users_in_public_rooms
+DROP TABLE IF EXISTS users_who_share_public_rooms;
+
+-- Track what users are in public rooms.
+CREATE TABLE IF NOT EXISTS users_in_public_rooms (
+    user_id TEXT NOT NULL,
+    room_id TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX users_in_public_rooms_u_idx ON users_in_public_rooms(user_id, room_id);
diff --git a/synapse/storage/databases/main/schema/delta/54/account_validity_with_renewal.sql b/synapse/storage/databases/main/schema/delta/54/account_validity_with_renewal.sql
new file mode 100644
index 0000000000..0adb2ad55e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/account_validity_with_renewal.sql
@@ -0,0 +1,30 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We previously changed the schema for this table without renaming the file, which means
+-- that some databases might still be using the old schema. This ensures Synapse uses the
+-- right schema for the table.
+DROP TABLE IF EXISTS account_validity;
+
+-- Track what users are in public rooms.
+CREATE TABLE IF NOT EXISTS account_validity (
+    user_id TEXT PRIMARY KEY,
+    expiration_ts_ms BIGINT NOT NULL,
+    email_sent BOOLEAN NOT NULL,
+    renewal_token TEXT
+);
+
+CREATE INDEX account_validity_email_sent_idx ON account_validity(email_sent, expiration_ts_ms)
+CREATE UNIQUE INDEX account_validity_renewal_string_idx ON account_validity(renewal_token)
diff --git a/synapse/storage/databases/main/schema/delta/54/add_validity_to_server_keys.sql b/synapse/storage/databases/main/schema/delta/54/add_validity_to_server_keys.sql
new file mode 100644
index 0000000000..c01aa9d2d9
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/add_validity_to_server_keys.sql
@@ -0,0 +1,23 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* When we can use this key until, before we have to refresh it. */
+ALTER TABLE server_signature_keys ADD COLUMN ts_valid_until_ms BIGINT;
+
+UPDATE server_signature_keys SET ts_valid_until_ms = (
+    SELECT MAX(ts_valid_until_ms) FROM server_keys_json skj WHERE
+        skj.server_name = server_signature_keys.server_name AND
+        skj.key_id = server_signature_keys.key_id
+);
diff --git a/synapse/storage/databases/main/schema/delta/54/delete_forward_extremities.sql b/synapse/storage/databases/main/schema/delta/54/delete_forward_extremities.sql
new file mode 100644
index 0000000000..b062ec840c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/delete_forward_extremities.sql
@@ -0,0 +1,23 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Start a background job to cleanup extremities that were incorrectly added
+-- by bug #5269.
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('delete_soft_failed_extremities', '{}');
+
+DROP TABLE IF EXISTS _extremities_to_check;  -- To make this delta schema file idempotent.
+CREATE TABLE _extremities_to_check AS SELECT event_id FROM event_forward_extremities;
+CREATE INDEX _extremities_to_check_id ON _extremities_to_check(event_id);
diff --git a/synapse/storage/databases/main/schema/delta/54/drop_legacy_tables.sql b/synapse/storage/databases/main/schema/delta/54/drop_legacy_tables.sql
new file mode 100644
index 0000000000..dbbe682697
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/drop_legacy_tables.sql
@@ -0,0 +1,30 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- we need to do this first due to foreign constraints
+DROP TABLE IF EXISTS application_services_regex;
+
+DROP TABLE IF EXISTS application_services;
+DROP TABLE IF EXISTS transaction_id_to_pdu;
+DROP TABLE IF EXISTS stats_reporting;
+DROP TABLE IF EXISTS current_state_resets;
+DROP TABLE IF EXISTS event_content_hashes;
+DROP TABLE IF EXISTS event_destinations;
+DROP TABLE IF EXISTS event_edge_hashes;
+DROP TABLE IF EXISTS event_signatures;
+DROP TABLE IF EXISTS feedback;
+DROP TABLE IF EXISTS room_hosts;
+DROP TABLE IF EXISTS server_tls_certificates;
+DROP TABLE IF EXISTS state_forward_extremities;
diff --git a/synapse/storage/databases/main/schema/delta/54/drop_presence_list.sql b/synapse/storage/databases/main/schema/delta/54/drop_presence_list.sql
new file mode 100644
index 0000000000..e6ee70c623
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/drop_presence_list.sql
@@ -0,0 +1,16 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+DROP TABLE IF EXISTS presence_list;
diff --git a/synapse/storage/databases/main/schema/delta/54/relations.sql b/synapse/storage/databases/main/schema/delta/54/relations.sql
new file mode 100644
index 0000000000..134862b870
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/relations.sql
@@ -0,0 +1,27 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Tracks related events, like reactions, replies, edits, etc. Note that things
+-- in this table are not necessarily "valid", e.g. it may contain edits from
+-- people who don't have power to edit other peoples events.
+CREATE TABLE IF NOT EXISTS event_relations (
+    event_id TEXT NOT NULL,
+    relates_to_id TEXT NOT NULL,
+    relation_type TEXT NOT NULL,
+    aggregation_key TEXT
+);
+
+CREATE UNIQUE INDEX event_relations_id ON event_relations(event_id);
+CREATE INDEX event_relations_relates ON event_relations(relates_to_id, relation_type, aggregation_key);
diff --git a/synapse/storage/databases/main/schema/delta/54/stats.sql b/synapse/storage/databases/main/schema/delta/54/stats.sql
new file mode 100644
index 0000000000..652e58308e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/stats.sql
@@ -0,0 +1,80 @@
+/* Copyright 2018 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE stats_stream_pos (
+    Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE,  -- Makes sure this table only has one row.
+    stream_id BIGINT,
+    CHECK (Lock='X')
+);
+
+INSERT INTO stats_stream_pos (stream_id) VALUES (null);
+
+CREATE TABLE user_stats (
+    user_id TEXT NOT NULL,
+    ts BIGINT NOT NULL,
+    bucket_size INT NOT NULL,
+    public_rooms INT NOT NULL,
+    private_rooms INT NOT NULL
+);
+
+CREATE UNIQUE INDEX user_stats_user_ts ON user_stats(user_id, ts);
+
+CREATE TABLE room_stats (
+    room_id TEXT NOT NULL,
+    ts BIGINT NOT NULL,
+    bucket_size INT NOT NULL,
+    current_state_events INT NOT NULL,
+    joined_members INT NOT NULL,
+    invited_members INT NOT NULL,
+    left_members INT NOT NULL,
+    banned_members INT NOT NULL,
+    state_events INT NOT NULL
+);
+
+CREATE UNIQUE INDEX room_stats_room_ts ON room_stats(room_id, ts);
+
+-- cache of current room state; useful for the publicRooms list
+CREATE TABLE room_state (
+    room_id TEXT NOT NULL,
+    join_rules TEXT,
+    history_visibility TEXT,
+    encryption TEXT,
+    name TEXT,
+    topic TEXT,
+    avatar TEXT,
+    canonical_alias TEXT
+    -- get aliases straight from the right table
+);
+
+CREATE UNIQUE INDEX room_state_room ON room_state(room_id);
+
+CREATE TABLE room_stats_earliest_token (
+    room_id TEXT NOT NULL,
+    token BIGINT NOT NULL
+);
+
+CREATE UNIQUE INDEX room_stats_earliest_token_idx ON room_stats_earliest_token(room_id);
+
+-- Set up staging tables
+INSERT INTO background_updates (update_name, progress_json) VALUES
+    ('populate_stats_createtables', '{}');
+
+-- Run through each room and update stats
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+    ('populate_stats_process_rooms', '{}', 'populate_stats_createtables');
+
+-- Clean up staging tables
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+    ('populate_stats_cleanup', '{}', 'populate_stats_process_rooms');
diff --git a/synapse/storage/databases/main/schema/delta/54/stats2.sql b/synapse/storage/databases/main/schema/delta/54/stats2.sql
new file mode 100644
index 0000000000..3b2d48447f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/54/stats2.sql
@@ -0,0 +1,28 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- This delta file gets run after `54/stats.sql` delta.
+
+-- We want to add some indices to the temporary stats table, so we re-insert
+-- 'populate_stats_createtables' if we are still processing the rooms update.
+INSERT INTO background_updates (update_name, progress_json)
+    SELECT 'populate_stats_createtables', '{}'
+    WHERE
+        'populate_stats_process_rooms' IN (
+            SELECT update_name FROM background_updates
+        )
+        AND 'populate_stats_createtables' NOT IN (  -- don't insert if already exists
+            SELECT update_name FROM background_updates
+        );
diff --git a/synapse/storage/databases/main/schema/delta/55/access_token_expiry.sql b/synapse/storage/databases/main/schema/delta/55/access_token_expiry.sql
new file mode 100644
index 0000000000..4590604bfd
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/55/access_token_expiry.sql
@@ -0,0 +1,18 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- when this access token can be used until, in ms since the epoch. NULL means the token
+-- never expires.
+ALTER TABLE access_tokens ADD COLUMN valid_until_ms BIGINT;
diff --git a/synapse/storage/databases/main/schema/delta/55/track_threepid_validations.sql b/synapse/storage/databases/main/schema/delta/55/track_threepid_validations.sql
new file mode 100644
index 0000000000..a8eced2e0a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/55/track_threepid_validations.sql
@@ -0,0 +1,31 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+CREATE TABLE IF NOT EXISTS threepid_validation_session (
+    session_id TEXT PRIMARY KEY,
+    medium TEXT NOT NULL,
+    address TEXT NOT NULL,
+    client_secret TEXT NOT NULL,
+    last_send_attempt BIGINT NOT NULL,
+    validated_at BIGINT
+);
+
+CREATE TABLE IF NOT EXISTS threepid_validation_token (
+    token TEXT PRIMARY KEY,
+    session_id TEXT NOT NULL,
+    next_link TEXT,
+    expires BIGINT NOT NULL
+);
+
+CREATE INDEX threepid_validation_token_session_id ON threepid_validation_token(session_id);
diff --git a/synapse/storage/databases/main/schema/delta/55/users_alter_deactivated.sql b/synapse/storage/databases/main/schema/delta/55/users_alter_deactivated.sql
new file mode 100644
index 0000000000..dabdde489b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/55/users_alter_deactivated.sql
@@ -0,0 +1,19 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE users ADD deactivated SMALLINT DEFAULT 0 NOT NULL;
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('users_set_deactivated_flag', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/add_spans_to_device_lists.sql b/synapse/storage/databases/main/schema/delta/56/add_spans_to_device_lists.sql
new file mode 100644
index 0000000000..41807eb1e7
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/add_spans_to_device_lists.sql
@@ -0,0 +1,20 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Opentracing context data for inclusion in the device_list_update EDUs, as a
+ * json-encoded dictionary. NULL if opentracing is disabled (or not enabled for this destination).
+ */
+ALTER TABLE device_lists_outbound_pokes ADD opentracing_context TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/56/current_state_events_membership.sql b/synapse/storage/databases/main/schema/delta/56/current_state_events_membership.sql
new file mode 100644
index 0000000000..473018676f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/current_state_events_membership.sql
@@ -0,0 +1,22 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We add membership to current state so that we don't need to join against
+-- room_memberships, which can be surprisingly costly (we do such queries
+-- very frequently).
+-- This will be null for non-membership events and the content.membership key
+-- for membership events. (Will also be null for membership events until the
+-- background update job has finished).
+ALTER TABLE current_state_events ADD membership TEXT;
diff --git a/synapse/storage/databases/main/schema/delta/56/current_state_events_membership_mk2.sql b/synapse/storage/databases/main/schema/delta/56/current_state_events_membership_mk2.sql
new file mode 100644
index 0000000000..3133d42d4a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/current_state_events_membership_mk2.sql
@@ -0,0 +1,24 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We add membership to current state so that we don't need to join against
+-- room_memberships, which can be surprisingly costly (we do such queries
+-- very frequently).
+-- This will be null for non-membership events and the content.membership key
+-- for membership events. (Will also be null for membership events until the
+-- background update job has finished).
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('current_state_events_membership', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/delete_keys_from_deleted_backups.sql b/synapse/storage/databases/main/schema/delta/56/delete_keys_from_deleted_backups.sql
new file mode 100644
index 0000000000..1d2ddb1b1a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/delete_keys_from_deleted_backups.sql
@@ -0,0 +1,25 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* delete room keys that belong to deleted room key version, or to room key
+ * versions that don't exist (anymore)
+ */
+DELETE FROM e2e_room_keys
+WHERE version NOT IN (
+  SELECT version
+  FROM e2e_room_keys_versions
+  WHERE e2e_room_keys.user_id = e2e_room_keys_versions.user_id
+  AND e2e_room_keys_versions.deleted = 0
+);
diff --git a/synapse/storage/databases/main/schema/delta/56/destinations_failure_ts.sql b/synapse/storage/databases/main/schema/delta/56/destinations_failure_ts.sql
new file mode 100644
index 0000000000..f00889290b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/destinations_failure_ts.sql
@@ -0,0 +1,25 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Record the timestamp when a given server started failing
+ */
+ALTER TABLE destinations ADD failure_ts BIGINT;
+
+/* as a rough approximation, we assume that the server started failing at
+ * retry_interval before the last retry
+ */
+UPDATE destinations SET failure_ts = retry_last_ts - retry_interval
+    WHERE retry_last_ts > 0;
diff --git a/synapse/storage/databases/main/schema/delta/56/destinations_retry_interval_type.sql.postgres b/synapse/storage/databases/main/schema/delta/56/destinations_retry_interval_type.sql.postgres
new file mode 100644
index 0000000000..b9bbb18a91
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/destinations_retry_interval_type.sql.postgres
@@ -0,0 +1,18 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We want to store large retry intervals so we upgrade the column from INT
+-- to BIGINT. We don't need to do this on SQLite.
+ALTER TABLE destinations ALTER retry_interval SET DATA TYPE BIGINT;
diff --git a/synapse/storage/databases/main/schema/delta/56/device_stream_id_insert.sql b/synapse/storage/databases/main/schema/delta/56/device_stream_id_insert.sql
new file mode 100644
index 0000000000..c2f557fde9
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/device_stream_id_insert.sql
@@ -0,0 +1,20 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- This line already existed in deltas/35/device_stream_id but was not included in the
+-- 54 full schema SQL. Add some SQL here to insert the missing row if it does not exist
+INSERT INTO device_max_stream_id (stream_id) SELECT 0 WHERE NOT EXISTS (
+    SELECT * from device_max_stream_id
+);
\ No newline at end of file
diff --git a/synapse/storage/databases/main/schema/delta/56/devices_last_seen.sql b/synapse/storage/databases/main/schema/delta/56/devices_last_seen.sql
new file mode 100644
index 0000000000..dfa902d0ba
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/devices_last_seen.sql
@@ -0,0 +1,24 @@
+/* Copyright 2019 Matrix.org Foundation CIC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Track last seen information for a device in the devices table, rather
+-- than relying on it being in the user_ips table (which we want to be able
+-- to purge old entries from)
+ALTER TABLE devices ADD COLUMN last_seen BIGINT;
+ALTER TABLE devices ADD COLUMN ip TEXT;
+ALTER TABLE devices ADD COLUMN user_agent TEXT;
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('devices_last_seen', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/drop_unused_event_tables.sql b/synapse/storage/databases/main/schema/delta/56/drop_unused_event_tables.sql
new file mode 100644
index 0000000000..9f09922c67
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/drop_unused_event_tables.sql
@@ -0,0 +1,20 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- these tables are never used.
+DROP TABLE IF EXISTS room_names;
+DROP TABLE IF EXISTS topics;
+DROP TABLE IF EXISTS history_visibility;
+DROP TABLE IF EXISTS guest_access;
diff --git a/synapse/storage/databases/main/schema/delta/56/event_expiry.sql b/synapse/storage/databases/main/schema/delta/56/event_expiry.sql
new file mode 100644
index 0000000000..81a36a8b1d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/event_expiry.sql
@@ -0,0 +1,21 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS event_expiry (
+    event_id TEXT PRIMARY KEY,
+    expiry_ts BIGINT NOT NULL
+);
+
+CREATE INDEX event_expiry_expiry_ts_idx ON event_expiry(expiry_ts);
diff --git a/synapse/storage/databases/main/schema/delta/56/event_labels.sql b/synapse/storage/databases/main/schema/delta/56/event_labels.sql
new file mode 100644
index 0000000000..5e29c1da19
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/event_labels.sql
@@ -0,0 +1,30 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- room_id and topoligical_ordering are denormalised from the events table in order to
+-- make the index work.
+CREATE TABLE IF NOT EXISTS event_labels (
+    event_id TEXT,
+    label TEXT,
+    room_id TEXT NOT NULL,
+    topological_ordering BIGINT NOT NULL,
+    PRIMARY KEY(event_id, label)
+);
+
+
+-- This index enables an event pagination looking for a particular label to index the
+-- event_labels table first, which is much quicker than scanning the events table and then
+-- filtering by label, if the label is rarely used relative to the size of the room.
+CREATE INDEX event_labels_room_id_label_idx ON event_labels(room_id, label, topological_ordering);
diff --git a/synapse/storage/databases/main/schema/delta/56/event_labels_background_update.sql b/synapse/storage/databases/main/schema/delta/56/event_labels_background_update.sql
new file mode 100644
index 0000000000..5f5e0499ae
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/event_labels_background_update.sql
@@ -0,0 +1,17 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('event_store_labels', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/fix_room_keys_index.sql b/synapse/storage/databases/main/schema/delta/56/fix_room_keys_index.sql
new file mode 100644
index 0000000000..014cb3b538
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/fix_room_keys_index.sql
@@ -0,0 +1,18 @@
+/* Copyright 2019 Matrix.org Foundation CIC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- version is supposed to be part of the room keys index
+CREATE UNIQUE INDEX e2e_room_keys_with_version_idx ON e2e_room_keys(user_id, version, room_id, session_id);
+DROP INDEX IF EXISTS e2e_room_keys_idx;
diff --git a/synapse/storage/databases/main/schema/delta/56/hidden_devices.sql b/synapse/storage/databases/main/schema/delta/56/hidden_devices.sql
new file mode 100644
index 0000000000..67f8b20297
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/hidden_devices.sql
@@ -0,0 +1,18 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- device list needs to know which ones are "real" devices, and which ones are
+-- just used to avoid collisions
+ALTER TABLE devices ADD COLUMN hidden BOOLEAN DEFAULT FALSE;
diff --git a/synapse/storage/databases/main/schema/delta/56/hidden_devices_fix.sql.sqlite b/synapse/storage/databases/main/schema/delta/56/hidden_devices_fix.sql.sqlite
new file mode 100644
index 0000000000..e8b1fd35d8
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/hidden_devices_fix.sql.sqlite
@@ -0,0 +1,42 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* Change the hidden column from a default value of FALSE to a default value of
+ * 0, because sqlite3 prior to 3.23.0 caused the hidden column to contain the
+ * string 'FALSE', which is truthy.
+ *
+ * Since sqlite doesn't allow us to just change the default value, we have to
+ * recreate the table, copy the data, fix the rows that have incorrect data, and
+ * replace the old table with the new table.
+ */
+
+CREATE TABLE IF NOT EXISTS devices2 (
+    user_id TEXT NOT NULL,
+    device_id TEXT NOT NULL,
+    display_name TEXT,
+    last_seen BIGINT,
+    ip TEXT,
+    user_agent TEXT,
+    hidden BOOLEAN DEFAULT 0,
+    CONSTRAINT device_uniqueness UNIQUE (user_id, device_id)
+);
+
+INSERT INTO devices2 SELECT * FROM devices;
+
+UPDATE devices2 SET hidden = 0 WHERE hidden = 'FALSE';
+
+DROP TABLE devices;
+
+ALTER TABLE devices2 RENAME TO devices;
diff --git a/synapse/storage/databases/main/schema/delta/56/nuke_empty_communities_from_db.sql b/synapse/storage/databases/main/schema/delta/56/nuke_empty_communities_from_db.sql
new file mode 100644
index 0000000000..4f24c1405d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/nuke_empty_communities_from_db.sql
@@ -0,0 +1,29 @@
+/* Copyright 2019 Werner Sembach
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Groups/communities now get deleted when the last member leaves. This is a one time cleanup to remove old groups/communities that were already empty before that change was made.
+DELETE FROM group_attestations_remote WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_attestations_renewals WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_invites WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_roles WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_room_categories WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_rooms WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_summary_roles WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_summary_room_categories WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_summary_rooms WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM group_summary_users WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM local_group_membership WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM local_group_updates WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
+DELETE FROM groups WHERE group_id IN (SELECT group_id FROM groups WHERE NOT EXISTS (SELECT group_id FROM group_users WHERE group_id = groups.group_id));
diff --git a/synapse/storage/databases/main/schema/delta/56/public_room_list_idx.sql b/synapse/storage/databases/main/schema/delta/56/public_room_list_idx.sql
new file mode 100644
index 0000000000..7be31ffebb
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/public_room_list_idx.sql
@@ -0,0 +1,16 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE INDEX public_room_list_stream_network ON public_room_list_stream (appservice_id, network_id, room_id);
diff --git a/synapse/storage/databases/main/schema/delta/56/redaction_censor.sql b/synapse/storage/databases/main/schema/delta/56/redaction_censor.sql
new file mode 100644
index 0000000000..ea95db0ed7
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/redaction_censor.sql
@@ -0,0 +1,16 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE redactions ADD COLUMN have_censored BOOL NOT NULL DEFAULT false;
diff --git a/synapse/storage/databases/main/schema/delta/56/redaction_censor2.sql b/synapse/storage/databases/main/schema/delta/56/redaction_censor2.sql
new file mode 100644
index 0000000000..49ce35d794
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/redaction_censor2.sql
@@ -0,0 +1,22 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ALTER TABLE redactions ADD COLUMN received_ts BIGINT;
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('redactions_received_ts', '{}');
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('redactions_have_censored_ts_idx', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/redaction_censor3_fix_update.sql.postgres b/synapse/storage/databases/main/schema/delta/56/redaction_censor3_fix_update.sql.postgres
new file mode 100644
index 0000000000..67471f3ef5
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/redaction_censor3_fix_update.sql.postgres
@@ -0,0 +1,25 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+-- There was a bug where we may have updated censored redactions as bytes,
+-- which can (somehow) cause json to be inserted hex encoded. These updates go
+-- and undoes any such hex encoded JSON.
+
+INSERT into background_updates (update_name, progress_json)
+  VALUES ('event_fix_redactions_bytes_create_index', '{}');
+
+INSERT into background_updates (update_name, progress_json, depends_on)
+  VALUES ('event_fix_redactions_bytes', '{}', 'event_fix_redactions_bytes_create_index');
diff --git a/synapse/storage/databases/main/schema/delta/56/redaction_censor4.sql b/synapse/storage/databases/main/schema/delta/56/redaction_censor4.sql
new file mode 100644
index 0000000000..b7550f6f4e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/redaction_censor4.sql
@@ -0,0 +1,16 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+DROP INDEX IF EXISTS redactions_have_censored;
diff --git a/synapse/storage/databases/main/schema/delta/56/remove_tombstoned_rooms_from_directory.sql b/synapse/storage/databases/main/schema/delta/56/remove_tombstoned_rooms_from_directory.sql
new file mode 100644
index 0000000000..aeb17813d3
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/remove_tombstoned_rooms_from_directory.sql
@@ -0,0 +1,18 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Now that #6232 is a thing, we can remove old rooms from the directory.
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('remove_tombstoned_rooms_from_directory', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/room_key_etag.sql b/synapse/storage/databases/main/schema/delta/56/room_key_etag.sql
new file mode 100644
index 0000000000..7d70dd071e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/room_key_etag.sql
@@ -0,0 +1,17 @@
+/* Copyright 2019 Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- store the current etag of backup version
+ALTER TABLE e2e_room_keys_versions ADD COLUMN etag BIGINT;
diff --git a/synapse/storage/databases/main/schema/delta/56/room_membership_idx.sql b/synapse/storage/databases/main/schema/delta/56/room_membership_idx.sql
new file mode 100644
index 0000000000..92ab1f5e65
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/room_membership_idx.sql
@@ -0,0 +1,18 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Adds an index on room_memberships for fetching all forgotten rooms for a user
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('room_membership_forgotten_idx', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/room_retention.sql b/synapse/storage/databases/main/schema/delta/56/room_retention.sql
new file mode 100644
index 0000000000..ee6cdf7a14
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/room_retention.sql
@@ -0,0 +1,33 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Tracks the retention policy of a room.
+-- A NULL max_lifetime or min_lifetime means that the matching property is not defined in
+-- the room's retention policy state event.
+-- If a room doesn't have a retention policy state event in its state, both max_lifetime
+-- and min_lifetime are NULL.
+CREATE TABLE IF NOT EXISTS room_retention(
+    room_id TEXT,
+    event_id TEXT,
+    min_lifetime BIGINT,
+    max_lifetime BIGINT,
+
+    PRIMARY KEY(room_id, event_id)
+);
+
+CREATE INDEX room_retention_max_lifetime_idx on room_retention(max_lifetime);
+
+INSERT INTO background_updates (update_name, progress_json) VALUES
+  ('insert_room_retention', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/56/signing_keys.sql b/synapse/storage/databases/main/schema/delta/56/signing_keys.sql
new file mode 100644
index 0000000000..5c5fffcafb
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/signing_keys.sql
@@ -0,0 +1,56 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- cross-signing keys
+CREATE TABLE IF NOT EXISTS e2e_cross_signing_keys (
+    user_id TEXT NOT NULL,
+    -- the type of cross-signing key (master, user_signing, or self_signing)
+    keytype TEXT NOT NULL,
+    -- the full key information, as a json-encoded dict
+    keydata TEXT NOT NULL,
+    -- for keeping the keys in order, so that we can fetch the latest one
+    stream_id BIGINT NOT NULL
+);
+
+CREATE UNIQUE INDEX e2e_cross_signing_keys_idx ON e2e_cross_signing_keys(user_id, keytype, stream_id);
+
+-- cross-signing signatures
+CREATE TABLE IF NOT EXISTS e2e_cross_signing_signatures (
+    -- user who did the signing
+    user_id TEXT NOT NULL,
+    -- key used to sign
+    key_id TEXT NOT NULL,
+    -- user who was signed
+    target_user_id TEXT NOT NULL,
+    -- device/key that was signed
+    target_device_id TEXT NOT NULL,
+    -- the actual signature
+    signature TEXT NOT NULL
+);
+
+-- replaced by the index created in signing_keys_nonunique_signatures.sql
+-- CREATE UNIQUE INDEX e2e_cross_signing_signatures_idx ON e2e_cross_signing_signatures(user_id, target_user_id, target_device_id);
+
+-- stream of user signature updates
+CREATE TABLE IF NOT EXISTS user_signature_stream (
+    -- uses the same stream ID as device list stream
+    stream_id BIGINT NOT NULL,
+    -- user who did the signing
+    from_user_id TEXT NOT NULL,
+    -- list of users who were signed, as a JSON array
+    user_ids TEXT NOT NULL
+);
+
+CREATE UNIQUE INDEX user_signature_stream_idx ON user_signature_stream(stream_id);
diff --git a/synapse/storage/databases/main/schema/delta/56/signing_keys_nonunique_signatures.sql b/synapse/storage/databases/main/schema/delta/56/signing_keys_nonunique_signatures.sql
new file mode 100644
index 0000000000..0aa90ebf0c
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/signing_keys_nonunique_signatures.sql
@@ -0,0 +1,22 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* The cross-signing signatures index should not be a unique index, because a
+ * user may upload multiple signatures for the same target user. The previous
+ * index was unique, so delete it if it's there and create a new non-unique
+ * index. */
+
+DROP INDEX IF EXISTS e2e_cross_signing_signatures_idx; CREATE INDEX IF NOT
+EXISTS e2e_cross_signing_signatures2_idx ON e2e_cross_signing_signatures(user_id, target_user_id, target_device_id);
diff --git a/synapse/storage/databases/main/schema/delta/56/stats_separated.sql b/synapse/storage/databases/main/schema/delta/56/stats_separated.sql
new file mode 100644
index 0000000000..bbdde121e8
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/stats_separated.sql
@@ -0,0 +1,156 @@
+/* Copyright 2018 New Vector Ltd
+ * Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+----- First clean up from previous versions of room stats.
+
+-- First remove old stats stuff
+DROP TABLE IF EXISTS room_stats;
+DROP TABLE IF EXISTS room_state;
+DROP TABLE IF EXISTS room_stats_state;
+DROP TABLE IF EXISTS user_stats;
+DROP TABLE IF EXISTS room_stats_earliest_tokens;
+DROP TABLE IF EXISTS _temp_populate_stats_position;
+DROP TABLE IF EXISTS _temp_populate_stats_rooms;
+DROP TABLE IF EXISTS stats_stream_pos;
+
+-- Unschedule old background updates if they're still scheduled
+DELETE FROM background_updates WHERE update_name IN (
+    'populate_stats_createtables',
+    'populate_stats_process_rooms',
+    'populate_stats_process_users',
+    'populate_stats_cleanup'
+);
+
+-- this relies on current_state_events.membership having been populated, so add
+-- a dependency on current_state_events_membership.
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+    ('populate_stats_process_rooms', '{}', 'current_state_events_membership');
+
+-- this also relies on current_state_events.membership having been populated, but
+-- we get that as a side-effect of depending on populate_stats_process_rooms.
+INSERT INTO background_updates (update_name, progress_json, depends_on) VALUES
+    ('populate_stats_process_users', '{}', 'populate_stats_process_rooms');
+
+----- Create tables for our version of room stats.
+
+-- single-row table to track position of incremental updates
+DROP TABLE IF EXISTS stats_incremental_position;
+CREATE TABLE stats_incremental_position (
+    Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE,  -- Makes sure this table only has one row.
+    stream_id  BIGINT NOT NULL,
+    CHECK (Lock='X')
+);
+
+-- insert a null row and make sure it is the only one.
+INSERT INTO stats_incremental_position (
+    stream_id
+) SELECT COALESCE(MAX(stream_ordering), 0) from events;
+
+-- represents PRESENT room statistics for a room
+-- only holds absolute fields
+DROP TABLE IF EXISTS room_stats_current;
+CREATE TABLE room_stats_current (
+    room_id TEXT NOT NULL PRIMARY KEY,
+
+    -- These are absolute counts
+    current_state_events INT NOT NULL,
+    joined_members INT NOT NULL,
+    invited_members INT NOT NULL,
+    left_members INT NOT NULL,
+    banned_members INT NOT NULL,
+
+    local_users_in_room INT NOT NULL,
+
+    -- The maximum delta stream position that this row takes into account.
+    completed_delta_stream_id BIGINT NOT NULL
+);
+
+
+-- represents HISTORICAL room statistics for a room
+DROP TABLE IF EXISTS room_stats_historical;
+CREATE TABLE room_stats_historical (
+    room_id TEXT NOT NULL,
+    -- These stats cover the time from (end_ts - bucket_size)...end_ts (in ms).
+    -- Note that end_ts is quantised.
+    end_ts BIGINT NOT NULL,
+    bucket_size BIGINT NOT NULL,
+
+    -- These stats are absolute counts
+    current_state_events BIGINT NOT NULL,
+    joined_members BIGINT NOT NULL,
+    invited_members BIGINT NOT NULL,
+    left_members BIGINT NOT NULL,
+    banned_members BIGINT NOT NULL,
+    local_users_in_room BIGINT NOT NULL,
+
+    -- These stats are per time slice
+    total_events BIGINT NOT NULL,
+    total_event_bytes BIGINT NOT NULL,
+
+    PRIMARY KEY (room_id, end_ts)
+);
+
+-- We use this index to speed up deletion of ancient room stats.
+CREATE INDEX room_stats_historical_end_ts ON room_stats_historical (end_ts);
+
+-- represents PRESENT statistics for a user
+-- only holds absolute fields
+DROP TABLE IF EXISTS user_stats_current;
+CREATE TABLE user_stats_current (
+    user_id TEXT NOT NULL PRIMARY KEY,
+
+    joined_rooms BIGINT NOT NULL,
+
+    -- The maximum delta stream position that this row takes into account.
+    completed_delta_stream_id BIGINT NOT NULL
+);
+
+-- represents HISTORICAL statistics for a user
+DROP TABLE IF EXISTS user_stats_historical;
+CREATE TABLE user_stats_historical (
+    user_id TEXT NOT NULL,
+    end_ts BIGINT NOT NULL,
+    bucket_size BIGINT NOT NULL,
+
+    joined_rooms BIGINT NOT NULL,
+
+    invites_sent BIGINT NOT NULL,
+    rooms_created BIGINT NOT NULL,
+    total_events BIGINT NOT NULL,
+    total_event_bytes BIGINT NOT NULL,
+
+    PRIMARY KEY (user_id, end_ts)
+);
+
+-- We use this index to speed up deletion of ancient user stats.
+CREATE INDEX user_stats_historical_end_ts ON user_stats_historical (end_ts);
+
+
+CREATE TABLE room_stats_state (
+    room_id TEXT NOT NULL,
+    name TEXT,
+    canonical_alias TEXT,
+    join_rules TEXT,
+    history_visibility TEXT,
+    encryption TEXT,
+    avatar TEXT,
+    guest_access TEXT,
+    is_federatable BOOLEAN,
+    topic TEXT
+);
+
+CREATE UNIQUE INDEX room_stats_state_room ON room_stats_state(room_id);
diff --git a/synapse/storage/databases/main/schema/delta/56/unique_user_filter_index.py b/synapse/storage/databases/main/schema/delta/56/unique_user_filter_index.py
new file mode 100644
index 0000000000..1de8b54961
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/unique_user_filter_index.py
@@ -0,0 +1,52 @@
+import logging
+
+from synapse.storage.engines import PostgresEngine
+
+logger = logging.getLogger(__name__)
+
+
+"""
+This migration updates the user_filters table as follows:
+
+ - drops any (user_id, filter_id) duplicates
+ - makes the columns NON-NULLable
+ - turns the index into a UNIQUE index
+"""
+
+
+def run_upgrade(cur, database_engine, *args, **kwargs):
+    pass
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    if isinstance(database_engine, PostgresEngine):
+        select_clause = """
+            SELECT DISTINCT ON (user_id, filter_id) user_id, filter_id, filter_json
+            FROM user_filters
+        """
+    else:
+        select_clause = """
+            SELECT * FROM user_filters GROUP BY user_id, filter_id
+        """
+    sql = """
+            DROP TABLE IF EXISTS user_filters_migration;
+            DROP INDEX IF EXISTS user_filters_unique;
+            CREATE TABLE user_filters_migration (
+                user_id TEXT NOT NULL,
+                filter_id BIGINT NOT NULL,
+                filter_json BYTEA NOT NULL
+            );
+            INSERT INTO user_filters_migration (user_id, filter_id, filter_json)
+                %s;
+            CREATE UNIQUE INDEX user_filters_unique ON user_filters_migration
+                (user_id, filter_id);
+            DROP TABLE user_filters;
+            ALTER TABLE user_filters_migration RENAME TO user_filters;
+        """ % (
+        select_clause,
+    )
+
+    if isinstance(database_engine, PostgresEngine):
+        cur.execute(sql)
+    else:
+        cur.executescript(sql)
diff --git a/synapse/storage/databases/main/schema/delta/56/user_external_ids.sql b/synapse/storage/databases/main/schema/delta/56/user_external_ids.sql
new file mode 100644
index 0000000000..91390c4527
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/user_external_ids.sql
@@ -0,0 +1,24 @@
+/* Copyright 2019 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * a table which records mappings from external auth providers to mxids
+ */
+CREATE TABLE IF NOT EXISTS user_external_ids (
+    auth_provider TEXT NOT NULL,
+    external_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    UNIQUE (auth_provider, external_id)
+);
diff --git a/synapse/storage/databases/main/schema/delta/56/users_in_public_rooms_idx.sql b/synapse/storage/databases/main/schema/delta/56/users_in_public_rooms_idx.sql
new file mode 100644
index 0000000000..149f8be8b6
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/56/users_in_public_rooms_idx.sql
@@ -0,0 +1,17 @@
+/* Copyright 2019 Matrix.org Foundation CIC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- this was apparently forgotten when the table was created back in delta 53.
+CREATE INDEX users_in_public_rooms_r_idx ON users_in_public_rooms(room_id);
diff --git a/synapse/storage/databases/main/schema/delta/57/delete_old_current_state_events.sql b/synapse/storage/databases/main/schema/delta/57/delete_old_current_state_events.sql
new file mode 100644
index 0000000000..aec06c8261
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/delete_old_current_state_events.sql
@@ -0,0 +1,22 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Add background update to go and delete current state events for rooms the
+-- server is no longer in.
+--
+-- this relies on the 'membership' column of current_state_events, so make sure
+-- that's populated first!
+INSERT into background_updates (update_name, progress_json, depends_on)
+    VALUES ('delete_old_current_state_events', '{}', 'current_state_events_membership');
diff --git a/synapse/storage/databases/main/schema/delta/57/device_list_remote_cache_stale.sql b/synapse/storage/databases/main/schema/delta/57/device_list_remote_cache_stale.sql
new file mode 100644
index 0000000000..c3b6de2099
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/device_list_remote_cache_stale.sql
@@ -0,0 +1,25 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Records whether the server thinks that the remote users cached device lists
+-- may be out of date (e.g. if we have received a to device message from a
+-- device we don't know about).
+CREATE TABLE IF NOT EXISTS device_lists_remote_resync (
+    user_id TEXT NOT NULL,
+    added_ts BIGINT NOT NULL
+);
+
+CREATE UNIQUE INDEX device_lists_remote_resync_idx ON device_lists_remote_resync (user_id);
+CREATE INDEX device_lists_remote_resync_ts_idx ON device_lists_remote_resync (added_ts);
diff --git a/synapse/storage/databases/main/schema/delta/57/local_current_membership.py b/synapse/storage/databases/main/schema/delta/57/local_current_membership.py
new file mode 100644
index 0000000000..63b5acdcf7
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/local_current_membership.py
@@ -0,0 +1,98 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+# We create a new table called `local_current_membership` that stores the latest
+# membership state of local users in rooms, which helps track leaves/bans/etc
+# even if the server has left the room (and so has deleted the room from
+# `current_state_events`). This will also include outstanding invites for local
+# users for rooms the server isn't in.
+#
+# If the server isn't and hasn't been in the room then it will only include
+# outsstanding invites, and not e.g. pre-emptive bans of local users.
+#
+# If the server later rejoins a room `local_current_membership` can simply be
+# replaced with the new current state of the room (which results in the
+# equivalent behaviour as if the server had remained in the room).
+
+
+def run_upgrade(cur, database_engine, config, *args, **kwargs):
+    # We need to do the insert in `run_upgrade` section as we don't have access
+    # to `config` in `run_create`.
+
+    # This upgrade may take a bit of time for large servers (e.g. one minute for
+    # matrix.org) but means we avoid a lots of book keeping required to do it as
+    # a background update.
+
+    # We check if the `current_state_events.membership` is up to date by
+    # checking if the relevant background update has finished. If it has
+    # finished we can avoid doing a join against `room_memberships`, which
+    # speesd things up.
+    cur.execute(
+        """SELECT 1 FROM background_updates
+            WHERE update_name = 'current_state_events_membership'
+        """
+    )
+    current_state_membership_up_to_date = not bool(cur.fetchone())
+
+    # Cheekily drop and recreate indices, as that is faster.
+    cur.execute("DROP INDEX local_current_membership_idx")
+    cur.execute("DROP INDEX local_current_membership_room_idx")
+
+    if current_state_membership_up_to_date:
+        sql = """
+            INSERT INTO local_current_membership (room_id, user_id, event_id, membership)
+                SELECT c.room_id, state_key AS user_id, event_id, c.membership
+                FROM current_state_events AS c
+                WHERE type = 'm.room.member' AND c.membership IS NOT NULL AND state_key LIKE ?
+        """
+    else:
+        # We can't rely on the membership column, so we need to join against
+        # `room_memberships`.
+        sql = """
+            INSERT INTO local_current_membership (room_id, user_id, event_id, membership)
+                SELECT c.room_id, state_key AS user_id, event_id, r.membership
+                FROM current_state_events AS c
+                INNER JOIN room_memberships AS r USING (event_id)
+                WHERE type = 'm.room.member' AND state_key LIKE ?
+        """
+    sql = database_engine.convert_param_style(sql)
+    cur.execute(sql, ("%:" + config.server_name,))
+
+    cur.execute(
+        "CREATE UNIQUE INDEX local_current_membership_idx ON local_current_membership(user_id, room_id)"
+    )
+    cur.execute(
+        "CREATE INDEX local_current_membership_room_idx ON local_current_membership(room_id)"
+    )
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    cur.execute(
+        """
+        CREATE TABLE local_current_membership (
+            room_id TEXT NOT NULL,
+            user_id TEXT NOT NULL,
+            event_id TEXT NOT NULL,
+            membership TEXT NOT NULL
+        )"""
+    )
+
+    cur.execute(
+        "CREATE UNIQUE INDEX local_current_membership_idx ON local_current_membership(user_id, room_id)"
+    )
+    cur.execute(
+        "CREATE INDEX local_current_membership_room_idx ON local_current_membership(room_id)"
+    )
diff --git a/synapse/storage/databases/main/schema/delta/57/remove_sent_outbound_pokes.sql b/synapse/storage/databases/main/schema/delta/57/remove_sent_outbound_pokes.sql
new file mode 100644
index 0000000000..133d80af35
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/remove_sent_outbound_pokes.sql
@@ -0,0 +1,21 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- we no longer keep sent outbound device pokes in the db; clear them out
+-- so that we don't have to worry about them.
+--
+-- This is a sequence scan, but it doesn't take too long.
+
+DELETE FROM device_lists_outbound_pokes WHERE sent;
diff --git a/synapse/storage/databases/main/schema/delta/57/rooms_version_column.sql b/synapse/storage/databases/main/schema/delta/57/rooms_version_column.sql
new file mode 100644
index 0000000000..352a66f5b0
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/rooms_version_column.sql
@@ -0,0 +1,24 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+-- We want to start storing the room version independently of
+-- `current_state_events` so that we can delete stale entries from it without
+-- losing the information.
+ALTER TABLE rooms ADD COLUMN room_version TEXT;
+
+
+INSERT into background_updates (update_name, progress_json)
+    VALUES ('add_rooms_room_version_column', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/57/rooms_version_column_2.sql.postgres b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_2.sql.postgres
new file mode 100644
index 0000000000..c601cff6de
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_2.sql.postgres
@@ -0,0 +1,35 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- when we first added the room_version column, it was populated via a background
+-- update. We now need it to be populated before synapse starts, so we populate
+-- any remaining rows with a NULL room version now. For servers which have completed
+-- the background update, this will be pretty quick.
+
+-- the following query will set room_version to NULL if no create event is found for
+-- the room in current_state_events, and will set it to '1' if a create event with no
+-- room_version is found.
+
+UPDATE rooms SET room_version=(
+    SELECT COALESCE(json::json->'content'->>'room_version','1')
+    FROM current_state_events cse INNER JOIN event_json ej USING (event_id)
+    WHERE cse.room_id=rooms.room_id AND cse.type='m.room.create' AND cse.state_key=''
+) WHERE rooms.room_version IS NULL;
+
+-- we still allow the background update to complete: it has the useful side-effect of
+-- populating `rooms` with any missing rooms (based on the current_state_events table).
+
+-- see also rooms_version_column_2.sql.sqlite which has a copy of the above query, using
+-- sqlite syntax for the json extraction.
diff --git a/synapse/storage/databases/main/schema/delta/57/rooms_version_column_2.sql.sqlite b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_2.sql.sqlite
new file mode 100644
index 0000000000..335c6f2074
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_2.sql.sqlite
@@ -0,0 +1,22 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- see rooms_version_column_2.sql.postgres for details of what's going on here.
+
+UPDATE rooms SET room_version=(
+    SELECT COALESCE(json_extract(ej.json, '$.content.room_version'), '1')
+    FROM current_state_events cse INNER JOIN event_json ej USING (event_id)
+    WHERE cse.room_id=rooms.room_id AND cse.type='m.room.create' AND cse.state_key=''
+) WHERE rooms.room_version IS NULL;
diff --git a/synapse/storage/databases/main/schema/delta/57/rooms_version_column_3.sql.postgres b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_3.sql.postgres
new file mode 100644
index 0000000000..92aaadde0d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_3.sql.postgres
@@ -0,0 +1,39 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- When we first added the room_version column to the rooms table, it was populated from
+-- the current_state_events table. However, there was an issue causing a background
+-- update to clean up the current_state_events table for rooms where the server is no
+-- longer participating, before that column could be populated. Therefore, some rooms had
+-- a NULL room_version.
+
+-- The rooms_version_column_2.sql.* delta files were introduced to make the populating
+-- synchronous instead of running it in a background update, which fixed this issue.
+-- However, all of the instances of Synapse installed or updated in the meantime got
+-- their rooms table corrupted with NULL room_versions.
+
+-- This query fishes out the room versions from the create event using the state_events
+-- table instead of the current_state_events one, as the former still have all of the
+-- create events.
+
+UPDATE rooms SET room_version=(
+    SELECT COALESCE(json::json->'content'->>'room_version','1')
+    FROM state_events se INNER JOIN event_json ej USING (event_id)
+    WHERE se.room_id=rooms.room_id AND se.type='m.room.create' AND se.state_key=''
+    LIMIT 1
+) WHERE rooms.room_version IS NULL;
+
+-- see also rooms_version_column_3.sql.sqlite which has a copy of the above query, using
+-- sqlite syntax for the json extraction.
diff --git a/synapse/storage/databases/main/schema/delta/57/rooms_version_column_3.sql.sqlite b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_3.sql.sqlite
new file mode 100644
index 0000000000..e19dab97cb
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/57/rooms_version_column_3.sql.sqlite
@@ -0,0 +1,23 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- see rooms_version_column_3.sql.postgres for details of what's going on here.
+
+UPDATE rooms SET room_version=(
+    SELECT COALESCE(json_extract(ej.json, '$.content.room_version'), '1')
+    FROM state_events se INNER JOIN event_json ej USING (event_id)
+    WHERE se.room_id=rooms.room_id AND se.type='m.room.create' AND se.state_key=''
+    LIMIT 1
+) WHERE rooms.room_version IS NULL;
diff --git a/synapse/storage/databases/main/schema/delta/58/02remove_dup_outbound_pokes.sql b/synapse/storage/databases/main/schema/delta/58/02remove_dup_outbound_pokes.sql
new file mode 100644
index 0000000000..fdc39e9ba5
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/02remove_dup_outbound_pokes.sql
@@ -0,0 +1,22 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ /* for some reason, we have accumulated duplicate entries in
+  * device_lists_outbound_pokes, which makes prune_outbound_device_list_pokes less
+  * efficient.
+  */
+
+INSERT INTO background_updates (ordering, update_name, progress_json)
+    VALUES (5800, 'remove_dup_outbound_pokes', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/58/03persist_ui_auth.sql b/synapse/storage/databases/main/schema/delta/58/03persist_ui_auth.sql
new file mode 100644
index 0000000000..dcb593fc2d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/03persist_ui_auth.sql
@@ -0,0 +1,36 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS ui_auth_sessions(
+    session_id TEXT NOT NULL,  -- The session ID passed to the client.
+    creation_time BIGINT NOT NULL,  -- The time this session was created (epoch time in milliseconds).
+    serverdict TEXT NOT NULL,  -- A JSON dictionary of arbitrary data added by Synapse.
+    clientdict TEXT NOT NULL,  -- A JSON dictionary of arbitrary data from the client.
+    uri TEXT NOT NULL,  -- The URI the UI authentication session is using.
+    method TEXT NOT NULL,  -- The HTTP method the UI authentication session is using.
+    -- The clientdict, uri, and method make up an tuple that must be immutable
+    -- throughout the lifetime of the UI Auth session.
+    description TEXT NOT NULL,  -- A human readable description of the operation which caused the UI Auth flow to occur.
+    UNIQUE (session_id)
+);
+
+CREATE TABLE IF NOT EXISTS ui_auth_sessions_credentials(
+    session_id TEXT NOT NULL,  -- The corresponding UI Auth session.
+    stage_type TEXT NOT NULL,  -- The stage type.
+    result TEXT NOT NULL,  -- The result of the stage verification, stored as JSON.
+    UNIQUE (session_id, stage_type),
+    FOREIGN KEY (session_id)
+        REFERENCES ui_auth_sessions (session_id)
+);
diff --git a/synapse/storage/databases/main/schema/delta/58/05cache_instance.sql.postgres b/synapse/storage/databases/main/schema/delta/58/05cache_instance.sql.postgres
new file mode 100644
index 0000000000..aa46eb0e10
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/05cache_instance.sql.postgres
@@ -0,0 +1,30 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We keep the old table here to enable us to roll back. It doesn't matter
+-- that we have dropped all the data here.
+TRUNCATE cache_invalidation_stream;
+
+CREATE TABLE cache_invalidation_stream_by_instance (
+    stream_id       BIGINT NOT NULL,
+    instance_name   TEXT NOT NULL,
+    cache_func      TEXT NOT NULL,
+    keys            TEXT[],
+    invalidation_ts BIGINT
+);
+
+CREATE UNIQUE INDEX cache_invalidation_stream_by_instance_id ON cache_invalidation_stream_by_instance(stream_id);
+
+CREATE SEQUENCE cache_invalidation_stream_seq;
diff --git a/synapse/storage/databases/main/schema/delta/58/06dlols_unique_idx.py b/synapse/storage/databases/main/schema/delta/58/06dlols_unique_idx.py
new file mode 100644
index 0000000000..d353f2bcb3
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/06dlols_unique_idx.py
@@ -0,0 +1,80 @@
+# Copyright 2020 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+This migration rebuilds the device_lists_outbound_last_success table without duplicate
+entries, and with a UNIQUE index.
+"""
+
+import logging
+from io import StringIO
+
+from synapse.storage.engines import BaseDatabaseEngine, PostgresEngine
+from synapse.storage.prepare_database import execute_statements_from_stream
+from synapse.storage.types import Cursor
+
+logger = logging.getLogger(__name__)
+
+
+def run_upgrade(*args, **kwargs):
+    pass
+
+
+def run_create(cur: Cursor, database_engine: BaseDatabaseEngine, *args, **kwargs):
+    # some instances might already have this index, in which case we can skip this
+    if isinstance(database_engine, PostgresEngine):
+        cur.execute(
+            """
+            SELECT 1 FROM pg_class WHERE relkind = 'i'
+            AND relname = 'device_lists_outbound_last_success_unique_idx'
+            """
+        )
+
+        if cur.rowcount:
+            logger.info(
+                "Unique index exists on device_lists_outbound_last_success: "
+                "skipping rebuild"
+            )
+            return
+
+    logger.info("Rebuilding device_lists_outbound_last_success with unique index")
+    execute_statements_from_stream(cur, StringIO(_rebuild_commands))
+
+
+# there might be duplicates, so the easiest way to achieve this is to create a new
+# table with the right data, and renaming it into place
+
+_rebuild_commands = """
+DROP TABLE IF EXISTS device_lists_outbound_last_success_new;
+
+CREATE TABLE device_lists_outbound_last_success_new (
+    destination TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    stream_id BIGINT NOT NULL
+);
+
+-- this took about 30 seconds on matrix.org's 16 million rows.
+INSERT INTO device_lists_outbound_last_success_new
+    SELECT destination, user_id, MAX(stream_id) FROM device_lists_outbound_last_success
+    GROUP BY destination, user_id;
+
+-- and this another 30 seconds.
+CREATE UNIQUE INDEX device_lists_outbound_last_success_unique_idx
+    ON device_lists_outbound_last_success_new (destination, user_id);
+
+DROP TABLE device_lists_outbound_last_success;
+
+ALTER TABLE device_lists_outbound_last_success_new
+    RENAME TO device_lists_outbound_last_success;
+"""
diff --git a/synapse/storage/databases/main/schema/delta/58/08_media_safe_from_quarantine.sql.postgres b/synapse/storage/databases/main/schema/delta/58/08_media_safe_from_quarantine.sql.postgres
new file mode 100644
index 0000000000..597f2ffd3d
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/08_media_safe_from_quarantine.sql.postgres
@@ -0,0 +1,18 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- The local_media_repository should have files which do not get quarantined,
+-- e.g. files from sticker packs.
+ALTER TABLE local_media_repository ADD COLUMN safe_from_quarantine BOOLEAN NOT NULL DEFAULT FALSE;
diff --git a/synapse/storage/databases/main/schema/delta/58/08_media_safe_from_quarantine.sql.sqlite b/synapse/storage/databases/main/schema/delta/58/08_media_safe_from_quarantine.sql.sqlite
new file mode 100644
index 0000000000..69db89ac0e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/08_media_safe_from_quarantine.sql.sqlite
@@ -0,0 +1,18 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- The local_media_repository should have files which do not get quarantined,
+-- e.g. files from sticker packs.
+ALTER TABLE local_media_repository ADD COLUMN safe_from_quarantine BOOLEAN NOT NULL DEFAULT 0;
diff --git a/synapse/storage/databases/main/schema/delta/58/10drop_local_rejections_stream.sql b/synapse/storage/databases/main/schema/delta/58/10drop_local_rejections_stream.sql
new file mode 100644
index 0000000000..eb57203e46
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/10drop_local_rejections_stream.sql
@@ -0,0 +1,22 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+The version of synapse 1.16.0 on pypi incorrectly contained a migration which
+added a table called 'local_rejections_stream'. This table is not used, and
+we drop it here for anyone who was affected.
+*/
+
+DROP TABLE IF EXISTS local_rejections_stream;
diff --git a/synapse/storage/databases/main/schema/delta/58/10federation_pos_instance_name.sql b/synapse/storage/databases/main/schema/delta/58/10federation_pos_instance_name.sql
new file mode 100644
index 0000000000..1cc2633aad
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/10federation_pos_instance_name.sql
@@ -0,0 +1,22 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We need to store the stream positions by instance in a sharded config world.
+--
+-- We default to master as we want the column to be NOT NULL and we correctly
+-- reset the instance name to match the config each time we start up.
+ALTER TABLE federation_stream_position ADD COLUMN instance_name TEXT NOT NULL DEFAULT 'master';
+
+CREATE UNIQUE INDEX federation_stream_position_instance ON federation_stream_position(type, instance_name);
diff --git a/synapse/storage/databases/main/schema/delta/58/11user_id_seq.py b/synapse/storage/databases/main/schema/delta/58/11user_id_seq.py
new file mode 100644
index 0000000000..4310ec12ce
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/11user_id_seq.py
@@ -0,0 +1,34 @@
+# Copyright 2020 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Adds a postgres SEQUENCE for generating guest user IDs.
+"""
+
+from synapse.storage.databases.main.registration import (
+    find_max_generated_user_id_localpart,
+)
+from synapse.storage.engines import PostgresEngine
+
+
+def run_create(cur, database_engine, *args, **kwargs):
+    if not isinstance(database_engine, PostgresEngine):
+        return
+
+    next_id = find_max_generated_user_id_localpart(cur) + 1
+    cur.execute("CREATE SEQUENCE user_id_seq START WITH %s", (next_id,))
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/databases/main/schema/delta/58/12room_stats.sql b/synapse/storage/databases/main/schema/delta/58/12room_stats.sql
new file mode 100644
index 0000000000..cade5dcca8
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/12room_stats.sql
@@ -0,0 +1,32 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Recalculate the stats for all rooms after the fix to joined_members erroneously
+-- incrementing on per-room profile changes.
+
+-- Note that the populate_stats_process_rooms background update is already set to
+-- run if you're upgrading from Synapse <1.0.0.
+
+-- Additionally, if you've upgraded to v1.18.0 (which doesn't include this fix),
+-- this bg job runs, and then update to v1.19.0, you'd end up with only half of
+-- your rooms having room stats recalculated after this fix was in place.
+
+-- So we've switched the old `populate_stats_process_rooms` background job to a
+-- no-op, and then kick off a bg job with a new name, but with the same
+-- functionality as the old one. This effectively restarts the background job
+-- from the beginning, without running it twice in a row, supporting both
+-- upgrade usecases.
+INSERT INTO background_updates (update_name, progress_json) VALUES
+    ('populate_stats_process_rooms_2', '{}');
diff --git a/synapse/storage/databases/main/schema/delta/58/12unread_messages.sql b/synapse/storage/databases/main/schema/delta/58/12unread_messages.sql
new file mode 100644
index 0000000000..531b532c73
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/58/12unread_messages.sql
@@ -0,0 +1,18 @@
+/* Copyright 2020 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- Store a boolean value in the events table for whether the event should be counted in
+-- the unread_count property of sync responses.
+ALTER TABLE events ADD COLUMN count_as_unread BOOLEAN;
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/application_services.sql b/synapse/storage/databases/main/schema/full_schemas/16/application_services.sql
new file mode 100644
index 0000000000..883fcd10b2
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/application_services.sql
@@ -0,0 +1,37 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* We used to create tables called application_services and
+ * application_services_regex, but these are no longer used and are removed in
+ * delta 54.
+ */
+
+
+CREATE TABLE IF NOT EXISTS application_services_state(
+    as_id TEXT PRIMARY KEY,
+    state VARCHAR(5),
+    last_txn INTEGER
+);
+
+CREATE TABLE IF NOT EXISTS application_services_txns(
+    as_id TEXT NOT NULL,
+    txn_id INTEGER NOT NULL,
+    event_ids TEXT NOT NULL,
+    UNIQUE(as_id, txn_id)
+);
+
+CREATE INDEX application_services_txns_id ON application_services_txns (
+    as_id
+);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/event_edges.sql b/synapse/storage/databases/main/schema/full_schemas/16/event_edges.sql
new file mode 100644
index 0000000000..10ce2aa7a0
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/event_edges.sql
@@ -0,0 +1,70 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* We used to create tables called event_destinations and
+ * state_forward_extremities, but these are no longer used and are removed in
+ * delta 54.
+ */
+
+CREATE TABLE IF NOT EXISTS event_forward_extremities(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    UNIQUE (event_id, room_id)
+);
+
+CREATE INDEX ev_extrem_room ON event_forward_extremities(room_id);
+CREATE INDEX ev_extrem_id ON event_forward_extremities(event_id);
+
+
+CREATE TABLE IF NOT EXISTS event_backward_extremities(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    UNIQUE (event_id, room_id)
+);
+
+CREATE INDEX ev_b_extrem_room ON event_backward_extremities(room_id);
+CREATE INDEX ev_b_extrem_id ON event_backward_extremities(event_id);
+
+
+CREATE TABLE IF NOT EXISTS event_edges(
+    event_id TEXT NOT NULL,
+    prev_event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    is_state BOOL NOT NULL,  -- true if this is a prev_state edge rather than a regular
+                             -- event dag edge.
+    UNIQUE (event_id, prev_event_id, room_id, is_state)
+);
+
+CREATE INDEX ev_edges_id ON event_edges(event_id);
+CREATE INDEX ev_edges_prev_id ON event_edges(prev_event_id);
+
+
+CREATE TABLE IF NOT EXISTS room_depth(
+    room_id TEXT NOT NULL,
+    min_depth INTEGER NOT NULL,
+    UNIQUE (room_id)
+);
+
+CREATE INDEX room_depth_room ON room_depth(room_id);
+
+CREATE TABLE IF NOT EXISTS event_auth(
+    event_id TEXT NOT NULL,
+    auth_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    UNIQUE (event_id, auth_id, room_id)
+);
+
+CREATE INDEX evauth_edges_id ON event_auth(event_id);
+CREATE INDEX evauth_edges_auth_id ON event_auth(auth_id);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/event_signatures.sql b/synapse/storage/databases/main/schema/full_schemas/16/event_signatures.sql
new file mode 100644
index 0000000000..95826da431
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/event_signatures.sql
@@ -0,0 +1,38 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ /* We used to create tables called event_content_hashes and event_edge_hashes,
+  * but these are no longer used and are removed in delta 54.
+  */
+
+CREATE TABLE IF NOT EXISTS event_reference_hashes (
+    event_id TEXT,
+    algorithm TEXT,
+    hash bytea,
+    UNIQUE (event_id, algorithm)
+);
+
+CREATE INDEX event_reference_hashes_id ON event_reference_hashes(event_id);
+
+
+CREATE TABLE IF NOT EXISTS event_signatures (
+    event_id TEXT,
+    signature_name TEXT,
+    key_id TEXT,
+    signature bytea,
+    UNIQUE (event_id, signature_name, key_id)
+);
+
+CREATE INDEX event_signatures_id ON event_signatures(event_id);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/im.sql b/synapse/storage/databases/main/schema/full_schemas/16/im.sql
new file mode 100644
index 0000000000..a1a2aa8e5b
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/im.sql
@@ -0,0 +1,120 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/* We used to create tables called room_hosts and feedback,
+ * but these are no longer used and are removed in delta 54.
+ */
+
+CREATE TABLE IF NOT EXISTS events(
+    stream_ordering INTEGER PRIMARY KEY,
+    topological_ordering BIGINT NOT NULL,
+    event_id TEXT NOT NULL,
+    type TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+
+    -- 'content' used to be created NULLable, but as of delta 50 we drop that constraint.
+    -- the hack we use to drop the constraint doesn't work for an in-memory sqlite
+    -- database, which breaks the sytests. Hence, we no longer make it nullable.
+    content TEXT,
+
+    unrecognized_keys TEXT,
+    processed BOOL NOT NULL,
+    outlier BOOL NOT NULL,
+    depth BIGINT DEFAULT 0 NOT NULL,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX events_stream_ordering ON events (stream_ordering);
+CREATE INDEX events_topological_ordering ON events (topological_ordering);
+CREATE INDEX events_order ON events (topological_ordering, stream_ordering);
+CREATE INDEX events_room_id ON events (room_id);
+CREATE INDEX events_order_room ON events (
+    room_id, topological_ordering, stream_ordering
+);
+
+
+CREATE TABLE IF NOT EXISTS event_json(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    internal_metadata TEXT NOT NULL,
+    json TEXT NOT NULL,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX event_json_room_id ON event_json(room_id);
+
+
+CREATE TABLE IF NOT EXISTS state_events(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    type TEXT NOT NULL,
+    state_key TEXT NOT NULL,
+    prev_state TEXT,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX state_events_room_id ON state_events (room_id);
+CREATE INDEX state_events_type ON state_events (type);
+CREATE INDEX state_events_state_key ON state_events (state_key);
+
+
+CREATE TABLE IF NOT EXISTS current_state_events(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    type TEXT NOT NULL,
+    state_key TEXT NOT NULL,
+    UNIQUE (event_id),
+    UNIQUE (room_id, type, state_key)
+);
+
+CREATE INDEX current_state_events_room_id ON current_state_events (room_id);
+CREATE INDEX current_state_events_type ON current_state_events (type);
+CREATE INDEX current_state_events_state_key ON current_state_events (state_key);
+
+CREATE TABLE IF NOT EXISTS room_memberships(
+    event_id TEXT NOT NULL,
+    user_id TEXT NOT NULL,
+    sender TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    membership TEXT NOT NULL,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX room_memberships_room_id ON room_memberships (room_id);
+CREATE INDEX room_memberships_user_id ON room_memberships (user_id);
+
+CREATE TABLE IF NOT EXISTS topics(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    topic TEXT NOT NULL,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX topics_room_id ON topics(room_id);
+
+CREATE TABLE IF NOT EXISTS room_names(
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    name TEXT NOT NULL,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX room_names_room_id ON room_names(room_id);
+
+CREATE TABLE IF NOT EXISTS rooms(
+    room_id TEXT PRIMARY KEY NOT NULL,
+    is_public BOOL,
+    creator TEXT
+);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/keys.sql b/synapse/storage/databases/main/schema/full_schemas/16/keys.sql
new file mode 100644
index 0000000000..11cdffdbb3
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/keys.sql
@@ -0,0 +1,26 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- we used to create a table called server_tls_certificates, but this is no
+-- longer used, and is removed in delta 54.
+
+CREATE TABLE IF NOT EXISTS server_signature_keys(
+  server_name TEXT, -- Server name.
+  key_id TEXT, -- Key version.
+  from_server TEXT, -- Which key server the key was fetched form.
+  ts_added_ms BIGINT, -- When the key was added.
+  verify_key bytea, -- NACL verification key.
+  UNIQUE (server_name, key_id)
+);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/media_repository.sql b/synapse/storage/databases/main/schema/full_schemas/16/media_repository.sql
new file mode 100644
index 0000000000..8f3759bb2a
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/media_repository.sql
@@ -0,0 +1,68 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS local_media_repository (
+    media_id TEXT, -- The id used to refer to the media.
+    media_type TEXT, -- The MIME-type of the media.
+    media_length INTEGER, -- Length of the media in bytes.
+    created_ts BIGINT, -- When the content was uploaded in ms.
+    upload_name TEXT, -- The name the media was uploaded with.
+    user_id TEXT, -- The user who uploaded the file.
+    UNIQUE (media_id)
+);
+
+CREATE TABLE IF NOT EXISTS local_media_repository_thumbnails (
+    media_id TEXT, -- The id used to refer to the media.
+    thumbnail_width INTEGER, -- The width of the thumbnail in pixels.
+    thumbnail_height INTEGER, -- The height of the thumbnail in pixels.
+    thumbnail_type TEXT, -- The MIME-type of the thumbnail.
+    thumbnail_method TEXT, -- The method used to make the thumbnail.
+    thumbnail_length INTEGER, -- The length of the thumbnail in bytes.
+    UNIQUE (
+        media_id, thumbnail_width, thumbnail_height, thumbnail_type
+    )
+);
+
+CREATE INDEX local_media_repository_thumbnails_media_id
+    ON local_media_repository_thumbnails (media_id);
+
+CREATE TABLE IF NOT EXISTS remote_media_cache (
+    media_origin TEXT, -- The remote HS the media came from.
+    media_id TEXT, -- The id used to refer to the media on that server.
+    media_type TEXT, -- The MIME-type of the media.
+    created_ts BIGINT, -- When the content was uploaded in ms.
+    upload_name TEXT, -- The name the media was uploaded with.
+    media_length INTEGER, -- Length of the media in bytes.
+    filesystem_id TEXT, -- The name used to store the media on disk.
+    UNIQUE (media_origin, media_id)
+);
+
+CREATE TABLE IF NOT EXISTS remote_media_cache_thumbnails (
+    media_origin TEXT, -- The remote HS the media came from.
+    media_id TEXT, -- The id used to refer to the media.
+    thumbnail_width INTEGER, -- The width of the thumbnail in pixels.
+    thumbnail_height INTEGER, -- The height of the thumbnail in pixels.
+    thumbnail_method TEXT, -- The method used to make the thumbnail
+    thumbnail_type TEXT, -- The MIME-type of the thumbnail.
+    thumbnail_length INTEGER, -- The length of the thumbnail in bytes.
+    filesystem_id TEXT, -- The name used to store the media on disk.
+    UNIQUE (
+        media_origin, media_id, thumbnail_width, thumbnail_height,
+        thumbnail_type
+     )
+);
+
+CREATE INDEX remote_media_cache_thumbnails_media_id
+    ON remote_media_cache_thumbnails (media_id);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/presence.sql b/synapse/storage/databases/main/schema/full_schemas/16/presence.sql
new file mode 100644
index 0000000000..01d2d8f833
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/presence.sql
@@ -0,0 +1,32 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+CREATE TABLE IF NOT EXISTS presence(
+  user_id TEXT NOT NULL,
+  state VARCHAR(20),
+  status_msg TEXT,
+  mtime BIGINT, -- miliseconds since last state change
+  UNIQUE (user_id)
+);
+
+-- For each of /my/ users which possibly-remote users are allowed to see their
+-- presence state
+CREATE TABLE IF NOT EXISTS presence_allow_inbound(
+  observed_user_id TEXT NOT NULL,
+  observer_user_id TEXT NOT NULL, -- a UserID,
+  UNIQUE (observed_user_id, observer_user_id)
+);
+
+-- We used to create a table called presence_list, but this is no longer used
+-- and is removed in delta 54.
\ No newline at end of file
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/profiles.sql b/synapse/storage/databases/main/schema/full_schemas/16/profiles.sql
new file mode 100644
index 0000000000..c04f4747d9
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/profiles.sql
@@ -0,0 +1,20 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+CREATE TABLE IF NOT EXISTS profiles(
+    user_id TEXT NOT NULL,
+    displayname TEXT,
+    avatar_url TEXT,
+    UNIQUE(user_id)
+);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/push.sql b/synapse/storage/databases/main/schema/full_schemas/16/push.sql
new file mode 100644
index 0000000000..e44465cf45
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/push.sql
@@ -0,0 +1,74 @@
+/* Copyright 2015, 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS rejections(
+    event_id TEXT NOT NULL,
+    reason TEXT NOT NULL,
+    last_check TEXT NOT NULL,
+    UNIQUE (event_id)
+);
+
+-- Push notification endpoints that users have configured
+CREATE TABLE IF NOT EXISTS pushers (
+  id BIGINT PRIMARY KEY,
+  user_name TEXT NOT NULL,
+  access_token BIGINT DEFAULT NULL,
+  profile_tag VARCHAR(32) NOT NULL,
+  kind VARCHAR(8) NOT NULL,
+  app_id VARCHAR(64) NOT NULL,
+  app_display_name VARCHAR(64) NOT NULL,
+  device_display_name VARCHAR(128) NOT NULL,
+  pushkey bytea NOT NULL,
+  ts BIGINT NOT NULL,
+  lang VARCHAR(8),
+  data bytea,
+  last_token TEXT,
+  last_success BIGINT,
+  failing_since BIGINT,
+  UNIQUE (app_id, pushkey)
+);
+
+CREATE TABLE IF NOT EXISTS push_rules (
+  id BIGINT PRIMARY KEY,
+  user_name TEXT NOT NULL,
+  rule_id TEXT NOT NULL,
+  priority_class SMALLINT NOT NULL,
+  priority INTEGER NOT NULL DEFAULT 0,
+  conditions TEXT NOT NULL,
+  actions TEXT NOT NULL,
+  UNIQUE(user_name, rule_id)
+);
+
+CREATE INDEX push_rules_user_name on push_rules (user_name);
+
+CREATE TABLE IF NOT EXISTS user_filters(
+  user_id TEXT,
+  filter_id BIGINT,
+  filter_json bytea
+);
+
+CREATE INDEX user_filters_by_user_id_filter_id ON user_filters(
+    user_id, filter_id
+);
+
+CREATE TABLE IF NOT EXISTS push_rules_enable (
+  id BIGINT PRIMARY KEY,
+  user_name TEXT NOT NULL,
+  rule_id TEXT NOT NULL,
+  enabled SMALLINT,
+  UNIQUE(user_name, rule_id)
+);
+
+CREATE INDEX push_rules_enable_user_name on push_rules_enable (user_name);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/redactions.sql b/synapse/storage/databases/main/schema/full_schemas/16/redactions.sql
new file mode 100644
index 0000000000..318f0d9aa5
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/redactions.sql
@@ -0,0 +1,22 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+CREATE TABLE IF NOT EXISTS redactions (
+    event_id TEXT NOT NULL,
+    redacts TEXT NOT NULL,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX redactions_event_id ON redactions (event_id);
+CREATE INDEX redactions_redacts ON redactions (redacts);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/room_aliases.sql b/synapse/storage/databases/main/schema/full_schemas/16/room_aliases.sql
new file mode 100644
index 0000000000..d47da3b12f
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/room_aliases.sql
@@ -0,0 +1,29 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS room_aliases(
+    room_alias TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    UNIQUE (room_alias)
+);
+
+CREATE INDEX room_aliases_id ON room_aliases(room_id);
+
+CREATE TABLE IF NOT EXISTS room_alias_servers(
+    room_alias TEXT NOT NULL,
+    server TEXT NOT NULL
+);
+
+CREATE INDEX room_alias_servers_alias ON room_alias_servers(room_alias);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/state.sql b/synapse/storage/databases/main/schema/full_schemas/16/state.sql
new file mode 100644
index 0000000000..96391a8f0e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/state.sql
@@ -0,0 +1,40 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+CREATE TABLE IF NOT EXISTS state_groups(
+    id BIGINT PRIMARY KEY,
+    room_id TEXT NOT NULL,
+    event_id TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS state_groups_state(
+    state_group BIGINT NOT NULL,
+    room_id TEXT NOT NULL,
+    type TEXT NOT NULL,
+    state_key TEXT NOT NULL,
+    event_id TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS event_to_state_groups(
+    event_id TEXT NOT NULL,
+    state_group BIGINT NOT NULL,
+    UNIQUE (event_id)
+);
+
+CREATE INDEX state_groups_id ON state_groups(id);
+
+CREATE INDEX state_groups_state_id ON state_groups_state(state_group);
+CREATE INDEX state_groups_state_tuple ON state_groups_state(room_id, type, state_key);
+CREATE INDEX event_to_state_groups_id ON event_to_state_groups(event_id);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/transactions.sql b/synapse/storage/databases/main/schema/full_schemas/16/transactions.sql
new file mode 100644
index 0000000000..17e67bedac
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/transactions.sql
@@ -0,0 +1,44 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+-- Stores what transaction ids we have received and what our response was
+CREATE TABLE IF NOT EXISTS received_transactions(
+    transaction_id TEXT,
+    origin TEXT,
+    ts BIGINT,
+    response_code INTEGER,
+    response_json bytea,
+    has_been_referenced smallint default 0, -- Whether thishas been referenced by a prev_tx
+    UNIQUE (transaction_id, origin)
+);
+
+CREATE INDEX transactions_have_ref ON received_transactions(origin, has_been_referenced);-- WHERE has_been_referenced = 0;
+
+-- For sent transactions only.
+CREATE TABLE IF NOT EXISTS transaction_id_to_pdu(
+    transaction_id INTEGER,
+    destination TEXT,
+    pdu_id TEXT,
+    pdu_origin TEXT,
+    UNIQUE (transaction_id, destination)
+);
+
+CREATE INDEX transaction_id_to_pdu_dest ON transaction_id_to_pdu(destination);
+
+-- To track destination health
+CREATE TABLE IF NOT EXISTS destinations(
+    destination TEXT PRIMARY KEY,
+    retry_last_ts BIGINT,
+    retry_interval INTEGER
+);
diff --git a/synapse/storage/databases/main/schema/full_schemas/16/users.sql b/synapse/storage/databases/main/schema/full_schemas/16/users.sql
new file mode 100644
index 0000000000..f013aa8b18
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/16/users.sql
@@ -0,0 +1,42 @@
+/* Copyright 2014-2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+CREATE TABLE IF NOT EXISTS users(
+    name TEXT,
+    password_hash TEXT,
+    creation_ts BIGINT,
+    admin SMALLINT DEFAULT 0 NOT NULL,
+    UNIQUE(name)
+);
+
+CREATE TABLE IF NOT EXISTS access_tokens(
+    id BIGINT PRIMARY KEY,
+    user_id TEXT NOT NULL,
+    device_id TEXT,
+    token TEXT NOT NULL,
+    last_used BIGINT,
+    UNIQUE(token)
+);
+
+CREATE TABLE IF NOT EXISTS user_ips (
+    user_id TEXT NOT NULL,
+    access_token TEXT NOT NULL,
+    device_id TEXT,
+    ip TEXT NOT NULL,
+    user_agent TEXT NOT NULL,
+    last_seen BIGINT NOT NULL
+);
+
+CREATE INDEX user_ips_user ON user_ips(user_id);
+CREATE INDEX user_ips_user_ip ON user_ips(user_id, access_token, ip);
diff --git a/synapse/storage/databases/main/schema/full_schemas/54/full.sql.postgres b/synapse/storage/databases/main/schema/full_schemas/54/full.sql.postgres
new file mode 100644
index 0000000000..889a9a0ce4
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/54/full.sql.postgres
@@ -0,0 +1,1983 @@
+
+
+
+
+
+CREATE TABLE access_tokens (
+    id bigint NOT NULL,
+    user_id text NOT NULL,
+    device_id text,
+    token text NOT NULL,
+    last_used bigint
+);
+
+
+
+CREATE TABLE account_data (
+    user_id text NOT NULL,
+    account_data_type text NOT NULL,
+    stream_id bigint NOT NULL,
+    content text NOT NULL
+);
+
+
+
+CREATE TABLE account_data_max_stream_id (
+    lock character(1) DEFAULT 'X'::bpchar NOT NULL,
+    stream_id bigint NOT NULL,
+    CONSTRAINT private_user_data_max_stream_id_lock_check CHECK ((lock = 'X'::bpchar))
+);
+
+
+
+CREATE TABLE account_validity (
+    user_id text NOT NULL,
+    expiration_ts_ms bigint NOT NULL,
+    email_sent boolean NOT NULL,
+    renewal_token text
+);
+
+
+
+CREATE TABLE application_services_state (
+    as_id text NOT NULL,
+    state character varying(5),
+    last_txn integer
+);
+
+
+
+CREATE TABLE application_services_txns (
+    as_id text NOT NULL,
+    txn_id integer NOT NULL,
+    event_ids text NOT NULL
+);
+
+
+
+CREATE TABLE appservice_room_list (
+    appservice_id text NOT NULL,
+    network_id text NOT NULL,
+    room_id text NOT NULL
+);
+
+
+
+CREATE TABLE appservice_stream_position (
+    lock character(1) DEFAULT 'X'::bpchar NOT NULL,
+    stream_ordering bigint,
+    CONSTRAINT appservice_stream_position_lock_check CHECK ((lock = 'X'::bpchar))
+);
+
+
+CREATE TABLE blocked_rooms (
+    room_id text NOT NULL,
+    user_id text NOT NULL
+);
+
+
+
+CREATE TABLE cache_invalidation_stream (
+    stream_id bigint,
+    cache_func text,
+    keys text[],
+    invalidation_ts bigint
+);
+
+
+
+CREATE TABLE current_state_delta_stream (
+    stream_id bigint NOT NULL,
+    room_id text NOT NULL,
+    type text NOT NULL,
+    state_key text NOT NULL,
+    event_id text,
+    prev_event_id text
+);
+
+
+
+CREATE TABLE current_state_events (
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    type text NOT NULL,
+    state_key text NOT NULL
+);
+
+
+
+CREATE TABLE deleted_pushers (
+    stream_id bigint NOT NULL,
+    app_id text NOT NULL,
+    pushkey text NOT NULL,
+    user_id text NOT NULL
+);
+
+
+
+CREATE TABLE destinations (
+    destination text NOT NULL,
+    retry_last_ts bigint,
+    retry_interval integer
+);
+
+
+
+CREATE TABLE device_federation_inbox (
+    origin text NOT NULL,
+    message_id text NOT NULL,
+    received_ts bigint NOT NULL
+);
+
+
+
+CREATE TABLE device_federation_outbox (
+    destination text NOT NULL,
+    stream_id bigint NOT NULL,
+    queued_ts bigint NOT NULL,
+    messages_json text NOT NULL
+);
+
+
+
+CREATE TABLE device_inbox (
+    user_id text NOT NULL,
+    device_id text NOT NULL,
+    stream_id bigint NOT NULL,
+    message_json text NOT NULL
+);
+
+
+
+CREATE TABLE device_lists_outbound_last_success (
+    destination text NOT NULL,
+    user_id text NOT NULL,
+    stream_id bigint NOT NULL
+);
+
+
+
+CREATE TABLE device_lists_outbound_pokes (
+    destination text NOT NULL,
+    stream_id bigint NOT NULL,
+    user_id text NOT NULL,
+    device_id text NOT NULL,
+    sent boolean NOT NULL,
+    ts bigint NOT NULL
+);
+
+
+
+CREATE TABLE device_lists_remote_cache (
+    user_id text NOT NULL,
+    device_id text NOT NULL,
+    content text NOT NULL
+);
+
+
+
+CREATE TABLE device_lists_remote_extremeties (
+    user_id text NOT NULL,
+    stream_id text NOT NULL
+);
+
+
+
+CREATE TABLE device_lists_stream (
+    stream_id bigint NOT NULL,
+    user_id text NOT NULL,
+    device_id text NOT NULL
+);
+
+
+
+CREATE TABLE device_max_stream_id (
+    stream_id bigint NOT NULL
+);
+
+
+
+CREATE TABLE devices (
+    user_id text NOT NULL,
+    device_id text NOT NULL,
+    display_name text
+);
+
+
+
+CREATE TABLE e2e_device_keys_json (
+    user_id text NOT NULL,
+    device_id text NOT NULL,
+    ts_added_ms bigint NOT NULL,
+    key_json text NOT NULL
+);
+
+
+
+CREATE TABLE e2e_one_time_keys_json (
+    user_id text NOT NULL,
+    device_id text NOT NULL,
+    algorithm text NOT NULL,
+    key_id text NOT NULL,
+    ts_added_ms bigint NOT NULL,
+    key_json text NOT NULL
+);
+
+
+
+CREATE TABLE e2e_room_keys (
+    user_id text NOT NULL,
+    room_id text NOT NULL,
+    session_id text NOT NULL,
+    version bigint NOT NULL,
+    first_message_index integer,
+    forwarded_count integer,
+    is_verified boolean,
+    session_data text NOT NULL
+);
+
+
+
+CREATE TABLE e2e_room_keys_versions (
+    user_id text NOT NULL,
+    version bigint NOT NULL,
+    algorithm text NOT NULL,
+    auth_data text NOT NULL,
+    deleted smallint DEFAULT 0 NOT NULL
+);
+
+
+
+CREATE TABLE erased_users (
+    user_id text NOT NULL
+);
+
+
+
+CREATE TABLE event_auth (
+    event_id text NOT NULL,
+    auth_id text NOT NULL,
+    room_id text NOT NULL
+);
+
+
+
+CREATE TABLE event_backward_extremities (
+    event_id text NOT NULL,
+    room_id text NOT NULL
+);
+
+
+
+CREATE TABLE event_edges (
+    event_id text NOT NULL,
+    prev_event_id text NOT NULL,
+    room_id text NOT NULL,
+    is_state boolean NOT NULL
+);
+
+
+
+CREATE TABLE event_forward_extremities (
+    event_id text NOT NULL,
+    room_id text NOT NULL
+);
+
+
+
+CREATE TABLE event_json (
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    internal_metadata text NOT NULL,
+    json text NOT NULL,
+    format_version integer
+);
+
+
+
+CREATE TABLE event_push_actions (
+    room_id text NOT NULL,
+    event_id text NOT NULL,
+    user_id text NOT NULL,
+    profile_tag character varying(32),
+    actions text NOT NULL,
+    topological_ordering bigint,
+    stream_ordering bigint,
+    notif smallint,
+    highlight smallint
+);
+
+
+
+CREATE TABLE event_push_actions_staging (
+    event_id text NOT NULL,
+    user_id text NOT NULL,
+    actions text NOT NULL,
+    notif smallint NOT NULL,
+    highlight smallint NOT NULL
+);
+
+
+
+CREATE TABLE event_push_summary (
+    user_id text NOT NULL,
+    room_id text NOT NULL,
+    notif_count bigint NOT NULL,
+    stream_ordering bigint NOT NULL
+);
+
+
+
+CREATE TABLE event_push_summary_stream_ordering (
+    lock character(1) DEFAULT 'X'::bpchar NOT NULL,
+    stream_ordering bigint NOT NULL,
+    CONSTRAINT event_push_summary_stream_ordering_lock_check CHECK ((lock = 'X'::bpchar))
+);
+
+
+
+CREATE TABLE event_reference_hashes (
+    event_id text,
+    algorithm text,
+    hash bytea
+);
+
+
+
+CREATE TABLE event_relations (
+    event_id text NOT NULL,
+    relates_to_id text NOT NULL,
+    relation_type text NOT NULL,
+    aggregation_key text
+);
+
+
+
+CREATE TABLE event_reports (
+    id bigint NOT NULL,
+    received_ts bigint NOT NULL,
+    room_id text NOT NULL,
+    event_id text NOT NULL,
+    user_id text NOT NULL,
+    reason text,
+    content text
+);
+
+
+
+CREATE TABLE event_search (
+    event_id text,
+    room_id text,
+    sender text,
+    key text,
+    vector tsvector,
+    origin_server_ts bigint,
+    stream_ordering bigint
+);
+
+
+
+CREATE TABLE event_to_state_groups (
+    event_id text NOT NULL,
+    state_group bigint NOT NULL
+);
+
+
+
+CREATE TABLE events (
+    stream_ordering integer NOT NULL,
+    topological_ordering bigint NOT NULL,
+    event_id text NOT NULL,
+    type text NOT NULL,
+    room_id text NOT NULL,
+    content text,
+    unrecognized_keys text,
+    processed boolean NOT NULL,
+    outlier boolean NOT NULL,
+    depth bigint DEFAULT 0 NOT NULL,
+    origin_server_ts bigint,
+    received_ts bigint,
+    sender text,
+    contains_url boolean
+);
+
+
+
+CREATE TABLE ex_outlier_stream (
+    event_stream_ordering bigint NOT NULL,
+    event_id text NOT NULL,
+    state_group bigint NOT NULL
+);
+
+
+
+CREATE TABLE federation_stream_position (
+    type text NOT NULL,
+    stream_id integer NOT NULL
+);
+
+
+
+CREATE TABLE group_attestations_remote (
+    group_id text NOT NULL,
+    user_id text NOT NULL,
+    valid_until_ms bigint NOT NULL,
+    attestation_json text NOT NULL
+);
+
+
+
+CREATE TABLE group_attestations_renewals (
+    group_id text NOT NULL,
+    user_id text NOT NULL,
+    valid_until_ms bigint NOT NULL
+);
+
+
+
+CREATE TABLE group_invites (
+    group_id text NOT NULL,
+    user_id text NOT NULL
+);
+
+
+
+CREATE TABLE group_roles (
+    group_id text NOT NULL,
+    role_id text NOT NULL,
+    profile text NOT NULL,
+    is_public boolean NOT NULL
+);
+
+
+
+CREATE TABLE group_room_categories (
+    group_id text NOT NULL,
+    category_id text NOT NULL,
+    profile text NOT NULL,
+    is_public boolean NOT NULL
+);
+
+
+
+CREATE TABLE group_rooms (
+    group_id text NOT NULL,
+    room_id text NOT NULL,
+    is_public boolean NOT NULL
+);
+
+
+
+CREATE TABLE group_summary_roles (
+    group_id text NOT NULL,
+    role_id text NOT NULL,
+    role_order bigint NOT NULL,
+    CONSTRAINT group_summary_roles_role_order_check CHECK ((role_order > 0))
+);
+
+
+
+CREATE TABLE group_summary_room_categories (
+    group_id text NOT NULL,
+    category_id text NOT NULL,
+    cat_order bigint NOT NULL,
+    CONSTRAINT group_summary_room_categories_cat_order_check CHECK ((cat_order > 0))
+);
+
+
+
+CREATE TABLE group_summary_rooms (
+    group_id text NOT NULL,
+    room_id text NOT NULL,
+    category_id text NOT NULL,
+    room_order bigint NOT NULL,
+    is_public boolean NOT NULL,
+    CONSTRAINT group_summary_rooms_room_order_check CHECK ((room_order > 0))
+);
+
+
+
+CREATE TABLE group_summary_users (
+    group_id text NOT NULL,
+    user_id text NOT NULL,
+    role_id text NOT NULL,
+    user_order bigint NOT NULL,
+    is_public boolean NOT NULL
+);
+
+
+
+CREATE TABLE group_users (
+    group_id text NOT NULL,
+    user_id text NOT NULL,
+    is_admin boolean NOT NULL,
+    is_public boolean NOT NULL
+);
+
+
+
+CREATE TABLE groups (
+    group_id text NOT NULL,
+    name text,
+    avatar_url text,
+    short_description text,
+    long_description text,
+    is_public boolean NOT NULL,
+    join_policy text DEFAULT 'invite'::text NOT NULL
+);
+
+
+
+CREATE TABLE guest_access (
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    guest_access text NOT NULL
+);
+
+
+
+CREATE TABLE history_visibility (
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    history_visibility text NOT NULL
+);
+
+
+
+CREATE TABLE local_group_membership (
+    group_id text NOT NULL,
+    user_id text NOT NULL,
+    is_admin boolean NOT NULL,
+    membership text NOT NULL,
+    is_publicised boolean NOT NULL,
+    content text NOT NULL
+);
+
+
+
+CREATE TABLE local_group_updates (
+    stream_id bigint NOT NULL,
+    group_id text NOT NULL,
+    user_id text NOT NULL,
+    type text NOT NULL,
+    content text NOT NULL
+);
+
+
+
+CREATE TABLE local_invites (
+    stream_id bigint NOT NULL,
+    inviter text NOT NULL,
+    invitee text NOT NULL,
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    locally_rejected text,
+    replaced_by text
+);
+
+
+
+CREATE TABLE local_media_repository (
+    media_id text,
+    media_type text,
+    media_length integer,
+    created_ts bigint,
+    upload_name text,
+    user_id text,
+    quarantined_by text,
+    url_cache text,
+    last_access_ts bigint
+);
+
+
+
+CREATE TABLE local_media_repository_thumbnails (
+    media_id text,
+    thumbnail_width integer,
+    thumbnail_height integer,
+    thumbnail_type text,
+    thumbnail_method text,
+    thumbnail_length integer
+);
+
+
+
+CREATE TABLE local_media_repository_url_cache (
+    url text,
+    response_code integer,
+    etag text,
+    expires_ts bigint,
+    og text,
+    media_id text,
+    download_ts bigint
+);
+
+
+
+CREATE TABLE monthly_active_users (
+    user_id text NOT NULL,
+    "timestamp" bigint NOT NULL
+);
+
+
+
+CREATE TABLE open_id_tokens (
+    token text NOT NULL,
+    ts_valid_until_ms bigint NOT NULL,
+    user_id text NOT NULL
+);
+
+
+
+CREATE TABLE presence (
+    user_id text NOT NULL,
+    state character varying(20),
+    status_msg text,
+    mtime bigint
+);
+
+
+
+CREATE TABLE presence_allow_inbound (
+    observed_user_id text NOT NULL,
+    observer_user_id text NOT NULL
+);
+
+
+
+CREATE TABLE presence_stream (
+    stream_id bigint,
+    user_id text,
+    state text,
+    last_active_ts bigint,
+    last_federation_update_ts bigint,
+    last_user_sync_ts bigint,
+    status_msg text,
+    currently_active boolean
+);
+
+
+
+CREATE TABLE profiles (
+    user_id text NOT NULL,
+    displayname text,
+    avatar_url text
+);
+
+
+
+CREATE TABLE public_room_list_stream (
+    stream_id bigint NOT NULL,
+    room_id text NOT NULL,
+    visibility boolean NOT NULL,
+    appservice_id text,
+    network_id text
+);
+
+
+
+CREATE TABLE push_rules (
+    id bigint NOT NULL,
+    user_name text NOT NULL,
+    rule_id text NOT NULL,
+    priority_class smallint NOT NULL,
+    priority integer DEFAULT 0 NOT NULL,
+    conditions text NOT NULL,
+    actions text NOT NULL
+);
+
+
+
+CREATE TABLE push_rules_enable (
+    id bigint NOT NULL,
+    user_name text NOT NULL,
+    rule_id text NOT NULL,
+    enabled smallint
+);
+
+
+
+CREATE TABLE push_rules_stream (
+    stream_id bigint NOT NULL,
+    event_stream_ordering bigint NOT NULL,
+    user_id text NOT NULL,
+    rule_id text NOT NULL,
+    op text NOT NULL,
+    priority_class smallint,
+    priority integer,
+    conditions text,
+    actions text
+);
+
+
+
+CREATE TABLE pusher_throttle (
+    pusher bigint NOT NULL,
+    room_id text NOT NULL,
+    last_sent_ts bigint,
+    throttle_ms bigint
+);
+
+
+
+CREATE TABLE pushers (
+    id bigint NOT NULL,
+    user_name text NOT NULL,
+    access_token bigint,
+    profile_tag text NOT NULL,
+    kind text NOT NULL,
+    app_id text NOT NULL,
+    app_display_name text NOT NULL,
+    device_display_name text NOT NULL,
+    pushkey text NOT NULL,
+    ts bigint NOT NULL,
+    lang text,
+    data text,
+    last_stream_ordering integer,
+    last_success bigint,
+    failing_since bigint
+);
+
+
+
+CREATE TABLE ratelimit_override (
+    user_id text NOT NULL,
+    messages_per_second bigint,
+    burst_count bigint
+);
+
+
+
+CREATE TABLE receipts_graph (
+    room_id text NOT NULL,
+    receipt_type text NOT NULL,
+    user_id text NOT NULL,
+    event_ids text NOT NULL,
+    data text NOT NULL
+);
+
+
+
+CREATE TABLE receipts_linearized (
+    stream_id bigint NOT NULL,
+    room_id text NOT NULL,
+    receipt_type text NOT NULL,
+    user_id text NOT NULL,
+    event_id text NOT NULL,
+    data text NOT NULL
+);
+
+
+
+CREATE TABLE received_transactions (
+    transaction_id text,
+    origin text,
+    ts bigint,
+    response_code integer,
+    response_json bytea,
+    has_been_referenced smallint DEFAULT 0
+);
+
+
+
+CREATE TABLE redactions (
+    event_id text NOT NULL,
+    redacts text NOT NULL
+);
+
+
+
+CREATE TABLE rejections (
+    event_id text NOT NULL,
+    reason text NOT NULL,
+    last_check text NOT NULL
+);
+
+
+
+CREATE TABLE remote_media_cache (
+    media_origin text,
+    media_id text,
+    media_type text,
+    created_ts bigint,
+    upload_name text,
+    media_length integer,
+    filesystem_id text,
+    last_access_ts bigint,
+    quarantined_by text
+);
+
+
+
+CREATE TABLE remote_media_cache_thumbnails (
+    media_origin text,
+    media_id text,
+    thumbnail_width integer,
+    thumbnail_height integer,
+    thumbnail_method text,
+    thumbnail_type text,
+    thumbnail_length integer,
+    filesystem_id text
+);
+
+
+
+CREATE TABLE remote_profile_cache (
+    user_id text NOT NULL,
+    displayname text,
+    avatar_url text,
+    last_check bigint NOT NULL
+);
+
+
+
+CREATE TABLE room_account_data (
+    user_id text NOT NULL,
+    room_id text NOT NULL,
+    account_data_type text NOT NULL,
+    stream_id bigint NOT NULL,
+    content text NOT NULL
+);
+
+
+
+CREATE TABLE room_alias_servers (
+    room_alias text NOT NULL,
+    server text NOT NULL
+);
+
+
+
+CREATE TABLE room_aliases (
+    room_alias text NOT NULL,
+    room_id text NOT NULL,
+    creator text
+);
+
+
+
+CREATE TABLE room_depth (
+    room_id text NOT NULL,
+    min_depth integer NOT NULL
+);
+
+
+
+CREATE TABLE room_memberships (
+    event_id text NOT NULL,
+    user_id text NOT NULL,
+    sender text NOT NULL,
+    room_id text NOT NULL,
+    membership text NOT NULL,
+    forgotten integer DEFAULT 0,
+    display_name text,
+    avatar_url text
+);
+
+
+
+CREATE TABLE room_names (
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    name text NOT NULL
+);
+
+
+
+CREATE TABLE room_state (
+    room_id text NOT NULL,
+    join_rules text,
+    history_visibility text,
+    encryption text,
+    name text,
+    topic text,
+    avatar text,
+    canonical_alias text
+);
+
+
+
+CREATE TABLE room_stats (
+    room_id text NOT NULL,
+    ts bigint NOT NULL,
+    bucket_size integer NOT NULL,
+    current_state_events integer NOT NULL,
+    joined_members integer NOT NULL,
+    invited_members integer NOT NULL,
+    left_members integer NOT NULL,
+    banned_members integer NOT NULL,
+    state_events integer NOT NULL
+);
+
+
+
+CREATE TABLE room_stats_earliest_token (
+    room_id text NOT NULL,
+    token bigint NOT NULL
+);
+
+
+
+CREATE TABLE room_tags (
+    user_id text NOT NULL,
+    room_id text NOT NULL,
+    tag text NOT NULL,
+    content text NOT NULL
+);
+
+
+
+CREATE TABLE room_tags_revisions (
+    user_id text NOT NULL,
+    room_id text NOT NULL,
+    stream_id bigint NOT NULL
+);
+
+
+
+CREATE TABLE rooms (
+    room_id text NOT NULL,
+    is_public boolean,
+    creator text
+);
+
+
+
+CREATE TABLE server_keys_json (
+    server_name text NOT NULL,
+    key_id text NOT NULL,
+    from_server text NOT NULL,
+    ts_added_ms bigint NOT NULL,
+    ts_valid_until_ms bigint NOT NULL,
+    key_json bytea NOT NULL
+);
+
+
+
+CREATE TABLE server_signature_keys (
+    server_name text,
+    key_id text,
+    from_server text,
+    ts_added_ms bigint,
+    verify_key bytea,
+    ts_valid_until_ms bigint
+);
+
+
+
+CREATE TABLE state_events (
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    type text NOT NULL,
+    state_key text NOT NULL,
+    prev_state text
+);
+
+
+
+CREATE TABLE stats_stream_pos (
+    lock character(1) DEFAULT 'X'::bpchar NOT NULL,
+    stream_id bigint,
+    CONSTRAINT stats_stream_pos_lock_check CHECK ((lock = 'X'::bpchar))
+);
+
+
+
+CREATE TABLE stream_ordering_to_exterm (
+    stream_ordering bigint NOT NULL,
+    room_id text NOT NULL,
+    event_id text NOT NULL
+);
+
+
+
+CREATE TABLE threepid_guest_access_tokens (
+    medium text,
+    address text,
+    guest_access_token text,
+    first_inviter text
+);
+
+
+
+CREATE TABLE topics (
+    event_id text NOT NULL,
+    room_id text NOT NULL,
+    topic text NOT NULL
+);
+
+
+
+CREATE TABLE user_daily_visits (
+    user_id text NOT NULL,
+    device_id text,
+    "timestamp" bigint NOT NULL
+);
+
+
+
+CREATE TABLE user_directory (
+    user_id text NOT NULL,
+    room_id text,
+    display_name text,
+    avatar_url text
+);
+
+
+
+CREATE TABLE user_directory_search (
+    user_id text NOT NULL,
+    vector tsvector
+);
+
+
+
+CREATE TABLE user_directory_stream_pos (
+    lock character(1) DEFAULT 'X'::bpchar NOT NULL,
+    stream_id bigint,
+    CONSTRAINT user_directory_stream_pos_lock_check CHECK ((lock = 'X'::bpchar))
+);
+
+
+
+CREATE TABLE user_filters (
+    user_id text,
+    filter_id bigint,
+    filter_json bytea
+);
+
+
+
+CREATE TABLE user_ips (
+    user_id text NOT NULL,
+    access_token text NOT NULL,
+    device_id text,
+    ip text NOT NULL,
+    user_agent text NOT NULL,
+    last_seen bigint NOT NULL
+);
+
+
+
+CREATE TABLE user_stats (
+    user_id text NOT NULL,
+    ts bigint NOT NULL,
+    bucket_size integer NOT NULL,
+    public_rooms integer NOT NULL,
+    private_rooms integer NOT NULL
+);
+
+
+
+CREATE TABLE user_threepid_id_server (
+    user_id text NOT NULL,
+    medium text NOT NULL,
+    address text NOT NULL,
+    id_server text NOT NULL
+);
+
+
+
+CREATE TABLE user_threepids (
+    user_id text NOT NULL,
+    medium text NOT NULL,
+    address text NOT NULL,
+    validated_at bigint NOT NULL,
+    added_at bigint NOT NULL
+);
+
+
+
+CREATE TABLE users (
+    name text,
+    password_hash text,
+    creation_ts bigint,
+    admin smallint DEFAULT 0 NOT NULL,
+    upgrade_ts bigint,
+    is_guest smallint DEFAULT 0 NOT NULL,
+    appservice_id text,
+    consent_version text,
+    consent_server_notice_sent text,
+    user_type text
+);
+
+
+
+CREATE TABLE users_in_public_rooms (
+    user_id text NOT NULL,
+    room_id text NOT NULL
+);
+
+
+
+CREATE TABLE users_pending_deactivation (
+    user_id text NOT NULL
+);
+
+
+
+CREATE TABLE users_who_share_private_rooms (
+    user_id text NOT NULL,
+    other_user_id text NOT NULL,
+    room_id text NOT NULL
+);
+
+
+
+ALTER TABLE ONLY access_tokens
+    ADD CONSTRAINT access_tokens_pkey PRIMARY KEY (id);
+
+
+
+ALTER TABLE ONLY access_tokens
+    ADD CONSTRAINT access_tokens_token_key UNIQUE (token);
+
+
+
+ALTER TABLE ONLY account_data
+    ADD CONSTRAINT account_data_uniqueness UNIQUE (user_id, account_data_type);
+
+
+
+ALTER TABLE ONLY account_validity
+    ADD CONSTRAINT account_validity_pkey PRIMARY KEY (user_id);
+
+
+
+ALTER TABLE ONLY application_services_state
+    ADD CONSTRAINT application_services_state_pkey PRIMARY KEY (as_id);
+
+
+
+ALTER TABLE ONLY application_services_txns
+    ADD CONSTRAINT application_services_txns_as_id_txn_id_key UNIQUE (as_id, txn_id);
+
+
+
+ALTER TABLE ONLY appservice_stream_position
+    ADD CONSTRAINT appservice_stream_position_lock_key UNIQUE (lock);
+
+
+
+ALTER TABLE ONLY current_state_events
+    ADD CONSTRAINT current_state_events_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY current_state_events
+    ADD CONSTRAINT current_state_events_room_id_type_state_key_key UNIQUE (room_id, type, state_key);
+
+
+
+ALTER TABLE ONLY destinations
+    ADD CONSTRAINT destinations_pkey PRIMARY KEY (destination);
+
+
+
+ALTER TABLE ONLY devices
+    ADD CONSTRAINT device_uniqueness UNIQUE (user_id, device_id);
+
+
+
+ALTER TABLE ONLY e2e_device_keys_json
+    ADD CONSTRAINT e2e_device_keys_json_uniqueness UNIQUE (user_id, device_id);
+
+
+
+ALTER TABLE ONLY e2e_one_time_keys_json
+    ADD CONSTRAINT e2e_one_time_keys_json_uniqueness UNIQUE (user_id, device_id, algorithm, key_id);
+
+
+
+ALTER TABLE ONLY event_backward_extremities
+    ADD CONSTRAINT event_backward_extremities_event_id_room_id_key UNIQUE (event_id, room_id);
+
+
+
+ALTER TABLE ONLY event_edges
+    ADD CONSTRAINT event_edges_event_id_prev_event_id_room_id_is_state_key UNIQUE (event_id, prev_event_id, room_id, is_state);
+
+
+
+ALTER TABLE ONLY event_forward_extremities
+    ADD CONSTRAINT event_forward_extremities_event_id_room_id_key UNIQUE (event_id, room_id);
+
+
+
+ALTER TABLE ONLY event_push_actions
+    ADD CONSTRAINT event_id_user_id_profile_tag_uniqueness UNIQUE (room_id, event_id, user_id, profile_tag);
+
+
+
+ALTER TABLE ONLY event_json
+    ADD CONSTRAINT event_json_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY event_push_summary_stream_ordering
+    ADD CONSTRAINT event_push_summary_stream_ordering_lock_key UNIQUE (lock);
+
+
+
+ALTER TABLE ONLY event_reference_hashes
+    ADD CONSTRAINT event_reference_hashes_event_id_algorithm_key UNIQUE (event_id, algorithm);
+
+
+
+ALTER TABLE ONLY event_reports
+    ADD CONSTRAINT event_reports_pkey PRIMARY KEY (id);
+
+
+
+ALTER TABLE ONLY event_to_state_groups
+    ADD CONSTRAINT event_to_state_groups_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY events
+    ADD CONSTRAINT events_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY events
+    ADD CONSTRAINT events_pkey PRIMARY KEY (stream_ordering);
+
+
+
+ALTER TABLE ONLY ex_outlier_stream
+    ADD CONSTRAINT ex_outlier_stream_pkey PRIMARY KEY (event_stream_ordering);
+
+
+
+ALTER TABLE ONLY group_roles
+    ADD CONSTRAINT group_roles_group_id_role_id_key UNIQUE (group_id, role_id);
+
+
+
+ALTER TABLE ONLY group_room_categories
+    ADD CONSTRAINT group_room_categories_group_id_category_id_key UNIQUE (group_id, category_id);
+
+
+
+ALTER TABLE ONLY group_summary_roles
+    ADD CONSTRAINT group_summary_roles_group_id_role_id_role_order_key UNIQUE (group_id, role_id, role_order);
+
+
+
+ALTER TABLE ONLY group_summary_room_categories
+    ADD CONSTRAINT group_summary_room_categories_group_id_category_id_cat_orde_key UNIQUE (group_id, category_id, cat_order);
+
+
+
+ALTER TABLE ONLY group_summary_rooms
+    ADD CONSTRAINT group_summary_rooms_group_id_category_id_room_id_room_order_key UNIQUE (group_id, category_id, room_id, room_order);
+
+
+
+ALTER TABLE ONLY guest_access
+    ADD CONSTRAINT guest_access_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY history_visibility
+    ADD CONSTRAINT history_visibility_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY local_media_repository
+    ADD CONSTRAINT local_media_repository_media_id_key UNIQUE (media_id);
+
+
+
+ALTER TABLE ONLY local_media_repository_thumbnails
+    ADD CONSTRAINT local_media_repository_thumbn_media_id_thumbnail_width_thum_key UNIQUE (media_id, thumbnail_width, thumbnail_height, thumbnail_type);
+
+
+
+ALTER TABLE ONLY user_threepids
+    ADD CONSTRAINT medium_address UNIQUE (medium, address);
+
+
+
+ALTER TABLE ONLY open_id_tokens
+    ADD CONSTRAINT open_id_tokens_pkey PRIMARY KEY (token);
+
+
+
+ALTER TABLE ONLY presence_allow_inbound
+    ADD CONSTRAINT presence_allow_inbound_observed_user_id_observer_user_id_key UNIQUE (observed_user_id, observer_user_id);
+
+
+
+ALTER TABLE ONLY presence
+    ADD CONSTRAINT presence_user_id_key UNIQUE (user_id);
+
+
+
+ALTER TABLE ONLY account_data_max_stream_id
+    ADD CONSTRAINT private_user_data_max_stream_id_lock_key UNIQUE (lock);
+
+
+
+ALTER TABLE ONLY profiles
+    ADD CONSTRAINT profiles_user_id_key UNIQUE (user_id);
+
+
+
+ALTER TABLE ONLY push_rules_enable
+    ADD CONSTRAINT push_rules_enable_pkey PRIMARY KEY (id);
+
+
+
+ALTER TABLE ONLY push_rules_enable
+    ADD CONSTRAINT push_rules_enable_user_name_rule_id_key UNIQUE (user_name, rule_id);
+
+
+
+ALTER TABLE ONLY push_rules
+    ADD CONSTRAINT push_rules_pkey PRIMARY KEY (id);
+
+
+
+ALTER TABLE ONLY push_rules
+    ADD CONSTRAINT push_rules_user_name_rule_id_key UNIQUE (user_name, rule_id);
+
+
+
+ALTER TABLE ONLY pusher_throttle
+    ADD CONSTRAINT pusher_throttle_pkey PRIMARY KEY (pusher, room_id);
+
+
+
+ALTER TABLE ONLY pushers
+    ADD CONSTRAINT pushers2_app_id_pushkey_user_name_key UNIQUE (app_id, pushkey, user_name);
+
+
+
+ALTER TABLE ONLY pushers
+    ADD CONSTRAINT pushers2_pkey PRIMARY KEY (id);
+
+
+
+ALTER TABLE ONLY receipts_graph
+    ADD CONSTRAINT receipts_graph_uniqueness UNIQUE (room_id, receipt_type, user_id);
+
+
+
+ALTER TABLE ONLY receipts_linearized
+    ADD CONSTRAINT receipts_linearized_uniqueness UNIQUE (room_id, receipt_type, user_id);
+
+
+
+ALTER TABLE ONLY received_transactions
+    ADD CONSTRAINT received_transactions_transaction_id_origin_key UNIQUE (transaction_id, origin);
+
+
+
+ALTER TABLE ONLY redactions
+    ADD CONSTRAINT redactions_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY rejections
+    ADD CONSTRAINT rejections_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY remote_media_cache
+    ADD CONSTRAINT remote_media_cache_media_origin_media_id_key UNIQUE (media_origin, media_id);
+
+
+
+ALTER TABLE ONLY remote_media_cache_thumbnails
+    ADD CONSTRAINT remote_media_cache_thumbnails_media_origin_media_id_thumbna_key UNIQUE (media_origin, media_id, thumbnail_width, thumbnail_height, thumbnail_type);
+
+
+
+ALTER TABLE ONLY room_account_data
+    ADD CONSTRAINT room_account_data_uniqueness UNIQUE (user_id, room_id, account_data_type);
+
+
+
+ALTER TABLE ONLY room_aliases
+    ADD CONSTRAINT room_aliases_room_alias_key UNIQUE (room_alias);
+
+
+
+ALTER TABLE ONLY room_depth
+    ADD CONSTRAINT room_depth_room_id_key UNIQUE (room_id);
+
+
+
+ALTER TABLE ONLY room_memberships
+    ADD CONSTRAINT room_memberships_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY room_names
+    ADD CONSTRAINT room_names_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY room_tags_revisions
+    ADD CONSTRAINT room_tag_revisions_uniqueness UNIQUE (user_id, room_id);
+
+
+
+ALTER TABLE ONLY room_tags
+    ADD CONSTRAINT room_tag_uniqueness UNIQUE (user_id, room_id, tag);
+
+
+
+ALTER TABLE ONLY rooms
+    ADD CONSTRAINT rooms_pkey PRIMARY KEY (room_id);
+
+
+
+ALTER TABLE ONLY server_keys_json
+    ADD CONSTRAINT server_keys_json_uniqueness UNIQUE (server_name, key_id, from_server);
+
+
+
+ALTER TABLE ONLY server_signature_keys
+    ADD CONSTRAINT server_signature_keys_server_name_key_id_key UNIQUE (server_name, key_id);
+
+
+
+ALTER TABLE ONLY state_events
+    ADD CONSTRAINT state_events_event_id_key UNIQUE (event_id);
+
+
+ALTER TABLE ONLY stats_stream_pos
+    ADD CONSTRAINT stats_stream_pos_lock_key UNIQUE (lock);
+
+
+
+ALTER TABLE ONLY topics
+    ADD CONSTRAINT topics_event_id_key UNIQUE (event_id);
+
+
+
+ALTER TABLE ONLY user_directory_stream_pos
+    ADD CONSTRAINT user_directory_stream_pos_lock_key UNIQUE (lock);
+
+
+
+ALTER TABLE ONLY users
+    ADD CONSTRAINT users_name_key UNIQUE (name);
+
+
+
+CREATE INDEX access_tokens_device_id ON access_tokens USING btree (user_id, device_id);
+
+
+
+CREATE INDEX account_data_stream_id ON account_data USING btree (user_id, stream_id);
+
+
+
+CREATE INDEX application_services_txns_id ON application_services_txns USING btree (as_id);
+
+
+
+CREATE UNIQUE INDEX appservice_room_list_idx ON appservice_room_list USING btree (appservice_id, network_id, room_id);
+
+
+
+CREATE UNIQUE INDEX blocked_rooms_idx ON blocked_rooms USING btree (room_id);
+
+
+
+CREATE INDEX cache_invalidation_stream_id ON cache_invalidation_stream USING btree (stream_id);
+
+
+
+CREATE INDEX current_state_delta_stream_idx ON current_state_delta_stream USING btree (stream_id);
+
+
+
+CREATE INDEX current_state_events_member_index ON current_state_events USING btree (state_key) WHERE (type = 'm.room.member'::text);
+
+
+
+CREATE INDEX deleted_pushers_stream_id ON deleted_pushers USING btree (stream_id);
+
+
+
+CREATE INDEX device_federation_inbox_sender_id ON device_federation_inbox USING btree (origin, message_id);
+
+
+
+CREATE INDEX device_federation_outbox_destination_id ON device_federation_outbox USING btree (destination, stream_id);
+
+
+
+CREATE INDEX device_federation_outbox_id ON device_federation_outbox USING btree (stream_id);
+
+
+
+CREATE INDEX device_inbox_stream_id_user_id ON device_inbox USING btree (stream_id, user_id);
+
+
+
+CREATE INDEX device_inbox_user_stream_id ON device_inbox USING btree (user_id, device_id, stream_id);
+
+
+
+CREATE INDEX device_lists_outbound_last_success_idx ON device_lists_outbound_last_success USING btree (destination, user_id, stream_id);
+
+
+
+CREATE INDEX device_lists_outbound_pokes_id ON device_lists_outbound_pokes USING btree (destination, stream_id);
+
+
+
+CREATE INDEX device_lists_outbound_pokes_stream ON device_lists_outbound_pokes USING btree (stream_id);
+
+
+
+CREATE INDEX device_lists_outbound_pokes_user ON device_lists_outbound_pokes USING btree (destination, user_id);
+
+
+
+CREATE UNIQUE INDEX device_lists_remote_cache_unique_id ON device_lists_remote_cache USING btree (user_id, device_id);
+
+
+
+CREATE UNIQUE INDEX device_lists_remote_extremeties_unique_idx ON device_lists_remote_extremeties USING btree (user_id);
+
+
+
+CREATE INDEX device_lists_stream_id ON device_lists_stream USING btree (stream_id, user_id);
+
+
+
+CREATE INDEX device_lists_stream_user_id ON device_lists_stream USING btree (user_id, device_id);
+
+
+
+CREATE UNIQUE INDEX e2e_room_keys_idx ON e2e_room_keys USING btree (user_id, room_id, session_id);
+
+
+
+CREATE UNIQUE INDEX e2e_room_keys_versions_idx ON e2e_room_keys_versions USING btree (user_id, version);
+
+
+
+CREATE UNIQUE INDEX erased_users_user ON erased_users USING btree (user_id);
+
+
+
+CREATE INDEX ev_b_extrem_id ON event_backward_extremities USING btree (event_id);
+
+
+
+CREATE INDEX ev_b_extrem_room ON event_backward_extremities USING btree (room_id);
+
+
+
+CREATE INDEX ev_edges_id ON event_edges USING btree (event_id);
+
+
+
+CREATE INDEX ev_edges_prev_id ON event_edges USING btree (prev_event_id);
+
+
+
+CREATE INDEX ev_extrem_id ON event_forward_extremities USING btree (event_id);
+
+
+
+CREATE INDEX ev_extrem_room ON event_forward_extremities USING btree (room_id);
+
+
+
+CREATE INDEX evauth_edges_id ON event_auth USING btree (event_id);
+
+
+
+CREATE INDEX event_contains_url_index ON events USING btree (room_id, topological_ordering, stream_ordering) WHERE ((contains_url = true) AND (outlier = false));
+
+
+
+CREATE INDEX event_json_room_id ON event_json USING btree (room_id);
+
+
+
+CREATE INDEX event_push_actions_highlights_index ON event_push_actions USING btree (user_id, room_id, topological_ordering, stream_ordering) WHERE (highlight = 1);
+
+
+
+CREATE INDEX event_push_actions_rm_tokens ON event_push_actions USING btree (user_id, room_id, topological_ordering, stream_ordering);
+
+
+
+CREATE INDEX event_push_actions_room_id_user_id ON event_push_actions USING btree (room_id, user_id);
+
+
+
+CREATE INDEX event_push_actions_staging_id ON event_push_actions_staging USING btree (event_id);
+
+
+
+CREATE INDEX event_push_actions_stream_ordering ON event_push_actions USING btree (stream_ordering, user_id);
+
+
+
+CREATE INDEX event_push_actions_u_highlight ON event_push_actions USING btree (user_id, stream_ordering);
+
+
+
+CREATE INDEX event_push_summary_user_rm ON event_push_summary USING btree (user_id, room_id);
+
+
+
+CREATE INDEX event_reference_hashes_id ON event_reference_hashes USING btree (event_id);
+
+
+
+CREATE UNIQUE INDEX event_relations_id ON event_relations USING btree (event_id);
+
+
+
+CREATE INDEX event_relations_relates ON event_relations USING btree (relates_to_id, relation_type, aggregation_key);
+
+
+
+CREATE INDEX event_search_ev_ridx ON event_search USING btree (room_id);
+
+
+
+CREATE UNIQUE INDEX event_search_event_id_idx ON event_search USING btree (event_id);
+
+
+
+CREATE INDEX event_search_fts_idx ON event_search USING gin (vector);
+
+
+
+CREATE INDEX event_to_state_groups_sg_index ON event_to_state_groups USING btree (state_group);
+
+
+
+CREATE INDEX events_order_room ON events USING btree (room_id, topological_ordering, stream_ordering);
+
+
+
+CREATE INDEX events_room_stream ON events USING btree (room_id, stream_ordering);
+
+
+
+CREATE INDEX events_ts ON events USING btree (origin_server_ts, stream_ordering);
+
+
+
+CREATE INDEX group_attestations_remote_g_idx ON group_attestations_remote USING btree (group_id, user_id);
+
+
+
+CREATE INDEX group_attestations_remote_u_idx ON group_attestations_remote USING btree (user_id);
+
+
+
+CREATE INDEX group_attestations_remote_v_idx ON group_attestations_remote USING btree (valid_until_ms);
+
+
+
+CREATE INDEX group_attestations_renewals_g_idx ON group_attestations_renewals USING btree (group_id, user_id);
+
+
+
+CREATE INDEX group_attestations_renewals_u_idx ON group_attestations_renewals USING btree (user_id);
+
+
+
+CREATE INDEX group_attestations_renewals_v_idx ON group_attestations_renewals USING btree (valid_until_ms);
+
+
+
+CREATE UNIQUE INDEX group_invites_g_idx ON group_invites USING btree (group_id, user_id);
+
+
+
+CREATE INDEX group_invites_u_idx ON group_invites USING btree (user_id);
+
+
+
+CREATE UNIQUE INDEX group_rooms_g_idx ON group_rooms USING btree (group_id, room_id);
+
+
+
+CREATE INDEX group_rooms_r_idx ON group_rooms USING btree (room_id);
+
+
+
+CREATE UNIQUE INDEX group_summary_rooms_g_idx ON group_summary_rooms USING btree (group_id, room_id, category_id);
+
+
+
+CREATE INDEX group_summary_users_g_idx ON group_summary_users USING btree (group_id);
+
+
+
+CREATE UNIQUE INDEX group_users_g_idx ON group_users USING btree (group_id, user_id);
+
+
+
+CREATE INDEX group_users_u_idx ON group_users USING btree (user_id);
+
+
+
+CREATE UNIQUE INDEX groups_idx ON groups USING btree (group_id);
+
+
+
+CREATE INDEX local_group_membership_g_idx ON local_group_membership USING btree (group_id);
+
+
+
+CREATE INDEX local_group_membership_u_idx ON local_group_membership USING btree (user_id, group_id);
+
+
+
+CREATE INDEX local_invites_for_user_idx ON local_invites USING btree (invitee, locally_rejected, replaced_by, room_id);
+
+
+
+CREATE INDEX local_invites_id ON local_invites USING btree (stream_id);
+
+
+
+CREATE INDEX local_media_repository_thumbnails_media_id ON local_media_repository_thumbnails USING btree (media_id);
+
+
+
+CREATE INDEX local_media_repository_url_cache_by_url_download_ts ON local_media_repository_url_cache USING btree (url, download_ts);
+
+
+
+CREATE INDEX local_media_repository_url_cache_expires_idx ON local_media_repository_url_cache USING btree (expires_ts);
+
+
+
+CREATE INDEX local_media_repository_url_cache_media_idx ON local_media_repository_url_cache USING btree (media_id);
+
+
+
+CREATE INDEX local_media_repository_url_idx ON local_media_repository USING btree (created_ts) WHERE (url_cache IS NOT NULL);
+
+
+
+CREATE INDEX monthly_active_users_time_stamp ON monthly_active_users USING btree ("timestamp");
+
+
+
+CREATE UNIQUE INDEX monthly_active_users_users ON monthly_active_users USING btree (user_id);
+
+
+
+CREATE INDEX open_id_tokens_ts_valid_until_ms ON open_id_tokens USING btree (ts_valid_until_ms);
+
+
+
+CREATE INDEX presence_stream_id ON presence_stream USING btree (stream_id, user_id);
+
+
+
+CREATE INDEX presence_stream_user_id ON presence_stream USING btree (user_id);
+
+
+
+CREATE INDEX public_room_index ON rooms USING btree (is_public);
+
+
+
+CREATE INDEX public_room_list_stream_idx ON public_room_list_stream USING btree (stream_id);
+
+
+
+CREATE INDEX public_room_list_stream_rm_idx ON public_room_list_stream USING btree (room_id, stream_id);
+
+
+
+CREATE INDEX push_rules_enable_user_name ON push_rules_enable USING btree (user_name);
+
+
+
+CREATE INDEX push_rules_stream_id ON push_rules_stream USING btree (stream_id);
+
+
+
+CREATE INDEX push_rules_stream_user_stream_id ON push_rules_stream USING btree (user_id, stream_id);
+
+
+
+CREATE INDEX push_rules_user_name ON push_rules USING btree (user_name);
+
+
+
+CREATE UNIQUE INDEX ratelimit_override_idx ON ratelimit_override USING btree (user_id);
+
+
+
+CREATE INDEX receipts_linearized_id ON receipts_linearized USING btree (stream_id);
+
+
+
+CREATE INDEX receipts_linearized_room_stream ON receipts_linearized USING btree (room_id, stream_id);
+
+
+
+CREATE INDEX receipts_linearized_user ON receipts_linearized USING btree (user_id);
+
+
+
+CREATE INDEX received_transactions_ts ON received_transactions USING btree (ts);
+
+
+
+CREATE INDEX redactions_redacts ON redactions USING btree (redacts);
+
+
+
+CREATE INDEX remote_profile_cache_time ON remote_profile_cache USING btree (last_check);
+
+
+
+CREATE UNIQUE INDEX remote_profile_cache_user_id ON remote_profile_cache USING btree (user_id);
+
+
+
+CREATE INDEX room_account_data_stream_id ON room_account_data USING btree (user_id, stream_id);
+
+
+
+CREATE INDEX room_alias_servers_alias ON room_alias_servers USING btree (room_alias);
+
+
+
+CREATE INDEX room_aliases_id ON room_aliases USING btree (room_id);
+
+
+
+CREATE INDEX room_depth_room ON room_depth USING btree (room_id);
+
+
+
+CREATE INDEX room_memberships_room_id ON room_memberships USING btree (room_id);
+
+
+
+CREATE INDEX room_memberships_user_id ON room_memberships USING btree (user_id);
+
+
+
+CREATE INDEX room_names_room_id ON room_names USING btree (room_id);
+
+
+
+CREATE UNIQUE INDEX room_state_room ON room_state USING btree (room_id);
+
+
+
+CREATE UNIQUE INDEX room_stats_earliest_token_idx ON room_stats_earliest_token USING btree (room_id);
+
+
+
+CREATE UNIQUE INDEX room_stats_room_ts ON room_stats USING btree (room_id, ts);
+
+
+
+CREATE INDEX stream_ordering_to_exterm_idx ON stream_ordering_to_exterm USING btree (stream_ordering);
+
+
+
+CREATE INDEX stream_ordering_to_exterm_rm_idx ON stream_ordering_to_exterm USING btree (room_id, stream_ordering);
+
+
+
+CREATE UNIQUE INDEX threepid_guest_access_tokens_index ON threepid_guest_access_tokens USING btree (medium, address);
+
+
+
+CREATE INDEX topics_room_id ON topics USING btree (room_id);
+
+
+
+CREATE INDEX user_daily_visits_ts_idx ON user_daily_visits USING btree ("timestamp");
+
+
+
+CREATE INDEX user_daily_visits_uts_idx ON user_daily_visits USING btree (user_id, "timestamp");
+
+
+
+CREATE INDEX user_directory_room_idx ON user_directory USING btree (room_id);
+
+
+
+CREATE INDEX user_directory_search_fts_idx ON user_directory_search USING gin (vector);
+
+
+
+CREATE UNIQUE INDEX user_directory_search_user_idx ON user_directory_search USING btree (user_id);
+
+
+
+CREATE UNIQUE INDEX user_directory_user_idx ON user_directory USING btree (user_id);
+
+
+
+CREATE INDEX user_filters_by_user_id_filter_id ON user_filters USING btree (user_id, filter_id);
+
+
+
+CREATE INDEX user_ips_device_id ON user_ips USING btree (user_id, device_id, last_seen);
+
+
+
+CREATE INDEX user_ips_last_seen ON user_ips USING btree (user_id, last_seen);
+
+
+
+CREATE INDEX user_ips_last_seen_only ON user_ips USING btree (last_seen);
+
+
+
+CREATE UNIQUE INDEX user_ips_user_token_ip_unique_index ON user_ips USING btree (user_id, access_token, ip);
+
+
+
+CREATE UNIQUE INDEX user_stats_user_ts ON user_stats USING btree (user_id, ts);
+
+
+
+CREATE UNIQUE INDEX user_threepid_id_server_idx ON user_threepid_id_server USING btree (user_id, medium, address, id_server);
+
+
+
+CREATE INDEX user_threepids_medium_address ON user_threepids USING btree (medium, address);
+
+
+
+CREATE INDEX user_threepids_user_id ON user_threepids USING btree (user_id);
+
+
+
+CREATE INDEX users_creation_ts ON users USING btree (creation_ts);
+
+
+
+CREATE UNIQUE INDEX users_in_public_rooms_u_idx ON users_in_public_rooms USING btree (user_id, room_id);
+
+
+
+CREATE INDEX users_who_share_private_rooms_o_idx ON users_who_share_private_rooms USING btree (other_user_id);
+
+
+
+CREATE INDEX users_who_share_private_rooms_r_idx ON users_who_share_private_rooms USING btree (room_id);
+
+
+
+CREATE UNIQUE INDEX users_who_share_private_rooms_u_idx ON users_who_share_private_rooms USING btree (user_id, other_user_id, room_id);
diff --git a/synapse/storage/databases/main/schema/full_schemas/54/full.sql.sqlite b/synapse/storage/databases/main/schema/full_schemas/54/full.sql.sqlite
new file mode 100644
index 0000000000..a0411ede7e
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/54/full.sql.sqlite
@@ -0,0 +1,253 @@
+CREATE TABLE application_services_state( as_id TEXT PRIMARY KEY, state VARCHAR(5), last_txn INTEGER );
+CREATE TABLE application_services_txns( as_id TEXT NOT NULL, txn_id INTEGER NOT NULL, event_ids TEXT NOT NULL, UNIQUE(as_id, txn_id) );
+CREATE INDEX application_services_txns_id ON application_services_txns ( as_id );
+CREATE TABLE presence( user_id TEXT NOT NULL, state VARCHAR(20), status_msg TEXT, mtime BIGINT, UNIQUE (user_id) );
+CREATE TABLE presence_allow_inbound( observed_user_id TEXT NOT NULL, observer_user_id TEXT NOT NULL, UNIQUE (observed_user_id, observer_user_id) );
+CREATE TABLE users( name TEXT, password_hash TEXT, creation_ts BIGINT, admin SMALLINT DEFAULT 0 NOT NULL, upgrade_ts BIGINT, is_guest SMALLINT DEFAULT 0 NOT NULL, appservice_id TEXT, consent_version TEXT, consent_server_notice_sent TEXT, user_type TEXT DEFAULT NULL, UNIQUE(name) );
+CREATE TABLE access_tokens( id BIGINT PRIMARY KEY, user_id TEXT NOT NULL, device_id TEXT, token TEXT NOT NULL, last_used BIGINT, UNIQUE(token) );
+CREATE TABLE user_ips ( user_id TEXT NOT NULL, access_token TEXT NOT NULL, device_id TEXT, ip TEXT NOT NULL, user_agent TEXT NOT NULL, last_seen BIGINT NOT NULL );
+CREATE TABLE profiles( user_id TEXT NOT NULL, displayname TEXT, avatar_url TEXT, UNIQUE(user_id) );
+CREATE TABLE received_transactions( transaction_id TEXT, origin TEXT, ts BIGINT, response_code INTEGER, response_json bytea, has_been_referenced smallint default 0, UNIQUE (transaction_id, origin) );
+CREATE TABLE destinations( destination TEXT PRIMARY KEY, retry_last_ts BIGINT, retry_interval INTEGER );
+CREATE TABLE events( stream_ordering INTEGER PRIMARY KEY, topological_ordering BIGINT NOT NULL, event_id TEXT NOT NULL, type TEXT NOT NULL, room_id TEXT NOT NULL, content TEXT, unrecognized_keys TEXT, processed BOOL NOT NULL, outlier BOOL NOT NULL, depth BIGINT DEFAULT 0 NOT NULL, origin_server_ts BIGINT, received_ts BIGINT, sender TEXT, contains_url BOOLEAN, UNIQUE (event_id) );
+CREATE INDEX events_order_room ON events ( room_id, topological_ordering, stream_ordering );
+CREATE TABLE event_json( event_id TEXT NOT NULL, room_id TEXT NOT NULL, internal_metadata TEXT NOT NULL, json TEXT NOT NULL, format_version INTEGER, UNIQUE (event_id) );
+CREATE INDEX event_json_room_id ON event_json(room_id);
+CREATE TABLE state_events( event_id TEXT NOT NULL, room_id TEXT NOT NULL, type TEXT NOT NULL, state_key TEXT NOT NULL, prev_state TEXT, UNIQUE (event_id) );
+CREATE TABLE current_state_events( event_id TEXT NOT NULL, room_id TEXT NOT NULL, type TEXT NOT NULL, state_key TEXT NOT NULL, UNIQUE (event_id), UNIQUE (room_id, type, state_key) );
+CREATE TABLE room_memberships( event_id TEXT NOT NULL, user_id TEXT NOT NULL, sender TEXT NOT NULL, room_id TEXT NOT NULL, membership TEXT NOT NULL, forgotten INTEGER DEFAULT 0, display_name TEXT, avatar_url TEXT, UNIQUE (event_id) );
+CREATE INDEX room_memberships_room_id ON room_memberships (room_id);
+CREATE INDEX room_memberships_user_id ON room_memberships (user_id);
+CREATE TABLE topics( event_id TEXT NOT NULL, room_id TEXT NOT NULL, topic TEXT NOT NULL, UNIQUE (event_id) );
+CREATE INDEX topics_room_id ON topics(room_id);
+CREATE TABLE room_names( event_id TEXT NOT NULL, room_id TEXT NOT NULL, name TEXT NOT NULL, UNIQUE (event_id) );
+CREATE INDEX room_names_room_id ON room_names(room_id);
+CREATE TABLE rooms( room_id TEXT PRIMARY KEY NOT NULL, is_public BOOL, creator TEXT );
+CREATE TABLE server_signature_keys( server_name TEXT, key_id TEXT, from_server TEXT, ts_added_ms BIGINT, verify_key bytea, ts_valid_until_ms BIGINT, UNIQUE (server_name, key_id) );
+CREATE TABLE rejections( event_id TEXT NOT NULL, reason TEXT NOT NULL, last_check TEXT NOT NULL, UNIQUE (event_id) );
+CREATE TABLE push_rules ( id BIGINT PRIMARY KEY, user_name TEXT NOT NULL, rule_id TEXT NOT NULL, priority_class SMALLINT NOT NULL, priority INTEGER NOT NULL DEFAULT 0, conditions TEXT NOT NULL, actions TEXT NOT NULL, UNIQUE(user_name, rule_id) );
+CREATE INDEX push_rules_user_name on push_rules (user_name);
+CREATE TABLE user_filters( user_id TEXT, filter_id BIGINT, filter_json bytea );
+CREATE INDEX user_filters_by_user_id_filter_id ON user_filters( user_id, filter_id );
+CREATE TABLE push_rules_enable ( id BIGINT PRIMARY KEY, user_name TEXT NOT NULL, rule_id TEXT NOT NULL, enabled SMALLINT, UNIQUE(user_name, rule_id) );
+CREATE INDEX push_rules_enable_user_name on push_rules_enable (user_name);
+CREATE TABLE event_forward_extremities( event_id TEXT NOT NULL, room_id TEXT NOT NULL, UNIQUE (event_id, room_id) );
+CREATE INDEX ev_extrem_room ON event_forward_extremities(room_id);
+CREATE INDEX ev_extrem_id ON event_forward_extremities(event_id);
+CREATE TABLE event_backward_extremities( event_id TEXT NOT NULL, room_id TEXT NOT NULL, UNIQUE (event_id, room_id) );
+CREATE INDEX ev_b_extrem_room ON event_backward_extremities(room_id);
+CREATE INDEX ev_b_extrem_id ON event_backward_extremities(event_id);
+CREATE TABLE event_edges( event_id TEXT NOT NULL, prev_event_id TEXT NOT NULL, room_id TEXT NOT NULL, is_state BOOL NOT NULL, UNIQUE (event_id, prev_event_id, room_id, is_state) );
+CREATE INDEX ev_edges_id ON event_edges(event_id);
+CREATE INDEX ev_edges_prev_id ON event_edges(prev_event_id);
+CREATE TABLE room_depth( room_id TEXT NOT NULL, min_depth INTEGER NOT NULL, UNIQUE (room_id) );
+CREATE INDEX room_depth_room ON room_depth(room_id);
+CREATE TABLE event_to_state_groups( event_id TEXT NOT NULL, state_group BIGINT NOT NULL, UNIQUE (event_id) );
+CREATE TABLE local_media_repository ( media_id TEXT, media_type TEXT, media_length INTEGER, created_ts BIGINT, upload_name TEXT, user_id TEXT, quarantined_by TEXT, url_cache TEXT, last_access_ts BIGINT, UNIQUE (media_id) );
+CREATE TABLE local_media_repository_thumbnails ( media_id TEXT, thumbnail_width INTEGER, thumbnail_height INTEGER, thumbnail_type TEXT, thumbnail_method TEXT, thumbnail_length INTEGER, UNIQUE ( media_id, thumbnail_width, thumbnail_height, thumbnail_type ) );
+CREATE INDEX local_media_repository_thumbnails_media_id ON local_media_repository_thumbnails (media_id);
+CREATE TABLE remote_media_cache ( media_origin TEXT, media_id TEXT, media_type TEXT, created_ts BIGINT, upload_name TEXT, media_length INTEGER, filesystem_id TEXT, last_access_ts BIGINT, quarantined_by TEXT, UNIQUE (media_origin, media_id) );
+CREATE TABLE remote_media_cache_thumbnails ( media_origin TEXT, media_id TEXT, thumbnail_width INTEGER, thumbnail_height INTEGER, thumbnail_method TEXT, thumbnail_type TEXT, thumbnail_length INTEGER, filesystem_id TEXT, UNIQUE ( media_origin, media_id, thumbnail_width, thumbnail_height, thumbnail_type ) );
+CREATE TABLE redactions ( event_id TEXT NOT NULL, redacts TEXT NOT NULL, UNIQUE (event_id) );
+CREATE INDEX redactions_redacts ON redactions (redacts);
+CREATE TABLE room_aliases( room_alias TEXT NOT NULL, room_id TEXT NOT NULL, creator TEXT, UNIQUE (room_alias) );
+CREATE INDEX room_aliases_id ON room_aliases(room_id);
+CREATE TABLE room_alias_servers( room_alias TEXT NOT NULL, server TEXT NOT NULL );
+CREATE INDEX room_alias_servers_alias ON room_alias_servers(room_alias);
+CREATE TABLE event_reference_hashes ( event_id TEXT, algorithm TEXT, hash bytea, UNIQUE (event_id, algorithm) );
+CREATE INDEX event_reference_hashes_id ON event_reference_hashes(event_id);
+CREATE TABLE IF NOT EXISTS "server_keys_json" ( server_name TEXT NOT NULL, key_id TEXT NOT NULL, from_server TEXT NOT NULL, ts_added_ms BIGINT NOT NULL, ts_valid_until_ms BIGINT NOT NULL, key_json bytea NOT NULL, CONSTRAINT server_keys_json_uniqueness UNIQUE (server_name, key_id, from_server) );
+CREATE TABLE e2e_device_keys_json ( user_id TEXT NOT NULL, device_id TEXT NOT NULL, ts_added_ms BIGINT NOT NULL, key_json TEXT NOT NULL, CONSTRAINT e2e_device_keys_json_uniqueness UNIQUE (user_id, device_id) );
+CREATE TABLE e2e_one_time_keys_json ( user_id TEXT NOT NULL, device_id TEXT NOT NULL, algorithm TEXT NOT NULL, key_id TEXT NOT NULL, ts_added_ms BIGINT NOT NULL, key_json TEXT NOT NULL, CONSTRAINT e2e_one_time_keys_json_uniqueness UNIQUE (user_id, device_id, algorithm, key_id) );
+CREATE TABLE receipts_graph( room_id TEXT NOT NULL, receipt_type TEXT NOT NULL, user_id TEXT NOT NULL, event_ids TEXT NOT NULL, data TEXT NOT NULL, CONSTRAINT receipts_graph_uniqueness UNIQUE (room_id, receipt_type, user_id) );
+CREATE TABLE receipts_linearized ( stream_id BIGINT NOT NULL, room_id TEXT NOT NULL, receipt_type TEXT NOT NULL, user_id TEXT NOT NULL, event_id TEXT NOT NULL, data TEXT NOT NULL, CONSTRAINT receipts_linearized_uniqueness UNIQUE (room_id, receipt_type, user_id) );
+CREATE INDEX receipts_linearized_id ON receipts_linearized( stream_id );
+CREATE INDEX receipts_linearized_room_stream ON receipts_linearized( room_id, stream_id );
+CREATE TABLE IF NOT EXISTS "user_threepids" ( user_id TEXT NOT NULL, medium TEXT NOT NULL, address TEXT NOT NULL, validated_at BIGINT NOT NULL, added_at BIGINT NOT NULL, CONSTRAINT medium_address UNIQUE (medium, address) );
+CREATE INDEX user_threepids_user_id ON user_threepids(user_id);
+CREATE VIRTUAL TABLE event_search USING fts4 ( event_id, room_id, sender, key, value )
+/* event_search(event_id,room_id,sender,"key",value) */;
+CREATE TABLE IF NOT EXISTS 'event_search_content'(docid INTEGER PRIMARY KEY, 'c0event_id', 'c1room_id', 'c2sender', 'c3key', 'c4value');
+CREATE TABLE IF NOT EXISTS 'event_search_segments'(blockid INTEGER PRIMARY KEY, block BLOB);
+CREATE TABLE IF NOT EXISTS 'event_search_segdir'(level INTEGER,idx INTEGER,start_block INTEGER,leaves_end_block INTEGER,end_block INTEGER,root BLOB,PRIMARY KEY(level, idx));
+CREATE TABLE IF NOT EXISTS 'event_search_docsize'(docid INTEGER PRIMARY KEY, size BLOB);
+CREATE TABLE IF NOT EXISTS 'event_search_stat'(id INTEGER PRIMARY KEY, value BLOB);
+CREATE TABLE guest_access( event_id TEXT NOT NULL, room_id TEXT NOT NULL, guest_access TEXT NOT NULL, UNIQUE (event_id) );
+CREATE TABLE history_visibility( event_id TEXT NOT NULL, room_id TEXT NOT NULL, history_visibility TEXT NOT NULL, UNIQUE (event_id) );
+CREATE TABLE room_tags( user_id TEXT NOT NULL, room_id TEXT NOT NULL, tag     TEXT NOT NULL, content TEXT NOT NULL, CONSTRAINT room_tag_uniqueness UNIQUE (user_id, room_id, tag) );
+CREATE TABLE room_tags_revisions ( user_id TEXT NOT NULL, room_id TEXT NOT NULL, stream_id BIGINT NOT NULL, CONSTRAINT room_tag_revisions_uniqueness UNIQUE (user_id, room_id) );
+CREATE TABLE IF NOT EXISTS "account_data_max_stream_id"( Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE, stream_id  BIGINT NOT NULL, CHECK (Lock='X') );
+CREATE TABLE account_data( user_id TEXT NOT NULL, account_data_type TEXT NOT NULL, stream_id BIGINT NOT NULL, content TEXT NOT NULL, CONSTRAINT account_data_uniqueness UNIQUE (user_id, account_data_type) );
+CREATE TABLE room_account_data( user_id TEXT NOT NULL, room_id TEXT NOT NULL, account_data_type TEXT NOT NULL, stream_id BIGINT NOT NULL, content TEXT NOT NULL, CONSTRAINT room_account_data_uniqueness UNIQUE (user_id, room_id, account_data_type) );
+CREATE INDEX account_data_stream_id on account_data(user_id, stream_id);
+CREATE INDEX room_account_data_stream_id on room_account_data(user_id, stream_id);
+CREATE INDEX events_ts ON events(origin_server_ts, stream_ordering);
+CREATE TABLE event_push_actions( room_id TEXT NOT NULL, event_id TEXT NOT NULL, user_id TEXT NOT NULL, profile_tag VARCHAR(32), actions TEXT NOT NULL, topological_ordering BIGINT, stream_ordering BIGINT, notif SMALLINT, highlight SMALLINT, CONSTRAINT event_id_user_id_profile_tag_uniqueness UNIQUE (room_id, event_id, user_id, profile_tag) );
+CREATE INDEX event_push_actions_room_id_user_id on event_push_actions(room_id, user_id);
+CREATE INDEX events_room_stream on events(room_id, stream_ordering);
+CREATE INDEX public_room_index on rooms(is_public);
+CREATE INDEX receipts_linearized_user ON receipts_linearized( user_id );
+CREATE INDEX event_push_actions_rm_tokens on event_push_actions( user_id, room_id, topological_ordering, stream_ordering );
+CREATE TABLE presence_stream( stream_id BIGINT, user_id TEXT, state TEXT, last_active_ts BIGINT, last_federation_update_ts BIGINT, last_user_sync_ts BIGINT, status_msg TEXT, currently_active BOOLEAN );
+CREATE INDEX presence_stream_id ON presence_stream(stream_id, user_id);
+CREATE INDEX presence_stream_user_id ON presence_stream(user_id);
+CREATE TABLE push_rules_stream( stream_id BIGINT NOT NULL, event_stream_ordering BIGINT NOT NULL, user_id TEXT NOT NULL, rule_id TEXT NOT NULL, op TEXT NOT NULL, priority_class SMALLINT, priority INTEGER, conditions TEXT, actions TEXT );
+CREATE INDEX push_rules_stream_id ON push_rules_stream(stream_id);
+CREATE INDEX push_rules_stream_user_stream_id on push_rules_stream(user_id, stream_id);
+CREATE TABLE ex_outlier_stream( event_stream_ordering BIGINT PRIMARY KEY NOT NULL, event_id TEXT NOT NULL, state_group BIGINT NOT NULL );
+CREATE TABLE threepid_guest_access_tokens( medium TEXT, address TEXT, guest_access_token TEXT, first_inviter TEXT );
+CREATE UNIQUE INDEX threepid_guest_access_tokens_index ON threepid_guest_access_tokens(medium, address);
+CREATE TABLE local_invites( stream_id BIGINT NOT NULL, inviter TEXT NOT NULL, invitee TEXT NOT NULL, event_id TEXT NOT NULL, room_id TEXT NOT NULL, locally_rejected TEXT, replaced_by TEXT );
+CREATE INDEX local_invites_id ON local_invites(stream_id);
+CREATE INDEX local_invites_for_user_idx ON local_invites(invitee, locally_rejected, replaced_by, room_id);
+CREATE INDEX event_push_actions_stream_ordering on event_push_actions( stream_ordering, user_id );
+CREATE TABLE open_id_tokens ( token TEXT NOT NULL PRIMARY KEY, ts_valid_until_ms bigint NOT NULL, user_id TEXT NOT NULL, UNIQUE (token) );
+CREATE INDEX open_id_tokens_ts_valid_until_ms ON open_id_tokens(ts_valid_until_ms);
+CREATE TABLE pusher_throttle( pusher BIGINT NOT NULL, room_id TEXT NOT NULL, last_sent_ts BIGINT, throttle_ms BIGINT, PRIMARY KEY (pusher, room_id) );
+CREATE TABLE event_reports( id BIGINT NOT NULL PRIMARY KEY, received_ts BIGINT NOT NULL, room_id TEXT NOT NULL, event_id TEXT NOT NULL, user_id TEXT NOT NULL, reason TEXT, content TEXT );
+CREATE TABLE devices ( user_id TEXT NOT NULL, device_id TEXT NOT NULL, display_name TEXT, CONSTRAINT device_uniqueness UNIQUE (user_id, device_id) );
+CREATE TABLE appservice_stream_position( Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE, stream_ordering BIGINT, CHECK (Lock='X') );
+CREATE TABLE device_inbox ( user_id TEXT NOT NULL, device_id TEXT NOT NULL, stream_id BIGINT NOT NULL, message_json TEXT NOT NULL );
+CREATE INDEX device_inbox_user_stream_id ON device_inbox(user_id, device_id, stream_id);
+CREATE INDEX received_transactions_ts ON received_transactions(ts);
+CREATE TABLE device_federation_outbox ( destination TEXT NOT NULL, stream_id BIGINT NOT NULL, queued_ts BIGINT NOT NULL, messages_json TEXT NOT NULL );
+CREATE INDEX device_federation_outbox_destination_id ON device_federation_outbox(destination, stream_id);
+CREATE TABLE device_federation_inbox ( origin TEXT NOT NULL, message_id TEXT NOT NULL, received_ts BIGINT NOT NULL );
+CREATE INDEX device_federation_inbox_sender_id ON device_federation_inbox(origin, message_id);
+CREATE TABLE device_max_stream_id ( stream_id BIGINT NOT NULL );
+CREATE TABLE public_room_list_stream ( stream_id BIGINT NOT NULL, room_id TEXT NOT NULL, visibility BOOLEAN NOT NULL , appservice_id TEXT, network_id TEXT);
+CREATE INDEX public_room_list_stream_idx on public_room_list_stream( stream_id );
+CREATE INDEX public_room_list_stream_rm_idx on public_room_list_stream( room_id, stream_id );
+CREATE TABLE stream_ordering_to_exterm ( stream_ordering BIGINT NOT NULL, room_id TEXT NOT NULL, event_id TEXT NOT NULL );
+CREATE INDEX stream_ordering_to_exterm_idx on stream_ordering_to_exterm( stream_ordering );
+CREATE INDEX stream_ordering_to_exterm_rm_idx on stream_ordering_to_exterm( room_id, stream_ordering );
+CREATE TABLE IF NOT EXISTS "event_auth"( event_id TEXT NOT NULL, auth_id TEXT NOT NULL, room_id TEXT NOT NULL );
+CREATE INDEX evauth_edges_id ON event_auth(event_id);
+CREATE INDEX user_threepids_medium_address on user_threepids (medium, address);
+CREATE TABLE appservice_room_list( appservice_id TEXT NOT NULL, network_id TEXT NOT NULL, room_id TEXT NOT NULL );
+CREATE UNIQUE INDEX appservice_room_list_idx ON appservice_room_list( appservice_id, network_id, room_id );
+CREATE INDEX device_federation_outbox_id ON device_federation_outbox(stream_id);
+CREATE TABLE federation_stream_position( type TEXT NOT NULL, stream_id INTEGER NOT NULL );
+CREATE TABLE device_lists_remote_cache ( user_id TEXT NOT NULL, device_id TEXT NOT NULL, content TEXT NOT NULL );
+CREATE TABLE device_lists_remote_extremeties ( user_id TEXT NOT NULL, stream_id TEXT NOT NULL );
+CREATE TABLE device_lists_stream ( stream_id BIGINT NOT NULL, user_id TEXT NOT NULL, device_id TEXT NOT NULL );
+CREATE INDEX device_lists_stream_id ON device_lists_stream(stream_id, user_id);
+CREATE TABLE device_lists_outbound_pokes ( destination TEXT NOT NULL, stream_id BIGINT NOT NULL, user_id TEXT NOT NULL, device_id TEXT NOT NULL, sent BOOLEAN NOT NULL, ts BIGINT NOT NULL );
+CREATE INDEX device_lists_outbound_pokes_id ON device_lists_outbound_pokes(destination, stream_id);
+CREATE INDEX device_lists_outbound_pokes_user ON device_lists_outbound_pokes(destination, user_id);
+CREATE TABLE event_push_summary ( user_id TEXT NOT NULL, room_id TEXT NOT NULL, notif_count BIGINT NOT NULL, stream_ordering BIGINT NOT NULL );
+CREATE INDEX event_push_summary_user_rm ON event_push_summary(user_id, room_id);
+CREATE TABLE event_push_summary_stream_ordering ( Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE, stream_ordering BIGINT NOT NULL, CHECK (Lock='X') );
+CREATE TABLE IF NOT EXISTS "pushers" ( id BIGINT PRIMARY KEY, user_name TEXT NOT NULL, access_token BIGINT DEFAULT NULL, profile_tag TEXT NOT NULL, kind TEXT NOT NULL, app_id TEXT NOT NULL, app_display_name TEXT NOT NULL, device_display_name TEXT NOT NULL, pushkey TEXT NOT NULL, ts BIGINT NOT NULL, lang TEXT, data TEXT, last_stream_ordering INTEGER, last_success BIGINT, failing_since BIGINT, UNIQUE (app_id, pushkey, user_name) );
+CREATE INDEX device_lists_outbound_pokes_stream ON device_lists_outbound_pokes(stream_id);
+CREATE TABLE ratelimit_override ( user_id TEXT NOT NULL, messages_per_second BIGINT, burst_count BIGINT );
+CREATE UNIQUE INDEX ratelimit_override_idx ON ratelimit_override(user_id);
+CREATE TABLE current_state_delta_stream ( stream_id BIGINT NOT NULL, room_id TEXT NOT NULL, type TEXT NOT NULL, state_key TEXT NOT NULL, event_id TEXT, prev_event_id TEXT );
+CREATE INDEX current_state_delta_stream_idx ON current_state_delta_stream(stream_id);
+CREATE TABLE device_lists_outbound_last_success ( destination TEXT NOT NULL, user_id TEXT NOT NULL, stream_id BIGINT NOT NULL );
+CREATE INDEX device_lists_outbound_last_success_idx ON device_lists_outbound_last_success( destination, user_id, stream_id );
+CREATE TABLE user_directory_stream_pos ( Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE, stream_id BIGINT, CHECK (Lock='X') );
+CREATE VIRTUAL TABLE user_directory_search USING fts4 ( user_id, value )
+/* user_directory_search(user_id,value) */;
+CREATE TABLE IF NOT EXISTS 'user_directory_search_content'(docid INTEGER PRIMARY KEY, 'c0user_id', 'c1value');
+CREATE TABLE IF NOT EXISTS 'user_directory_search_segments'(blockid INTEGER PRIMARY KEY, block BLOB);
+CREATE TABLE IF NOT EXISTS 'user_directory_search_segdir'(level INTEGER,idx INTEGER,start_block INTEGER,leaves_end_block INTEGER,end_block INTEGER,root BLOB,PRIMARY KEY(level, idx));
+CREATE TABLE IF NOT EXISTS 'user_directory_search_docsize'(docid INTEGER PRIMARY KEY, size BLOB);
+CREATE TABLE IF NOT EXISTS 'user_directory_search_stat'(id INTEGER PRIMARY KEY, value BLOB);
+CREATE TABLE blocked_rooms ( room_id TEXT NOT NULL, user_id TEXT NOT NULL );
+CREATE UNIQUE INDEX blocked_rooms_idx ON blocked_rooms(room_id);
+CREATE TABLE IF NOT EXISTS "local_media_repository_url_cache"( url TEXT, response_code INTEGER, etag TEXT, expires_ts BIGINT, og TEXT, media_id TEXT, download_ts BIGINT );
+CREATE INDEX local_media_repository_url_cache_expires_idx ON local_media_repository_url_cache(expires_ts);
+CREATE INDEX local_media_repository_url_cache_by_url_download_ts ON local_media_repository_url_cache(url, download_ts);
+CREATE INDEX local_media_repository_url_cache_media_idx ON local_media_repository_url_cache(media_id);
+CREATE TABLE group_users ( group_id TEXT NOT NULL, user_id TEXT NOT NULL, is_admin BOOLEAN NOT NULL, is_public BOOLEAN NOT NULL );
+CREATE TABLE group_invites ( group_id TEXT NOT NULL, user_id TEXT NOT NULL );
+CREATE TABLE group_rooms ( group_id TEXT NOT NULL, room_id TEXT NOT NULL, is_public BOOLEAN NOT NULL );
+CREATE TABLE group_summary_rooms ( group_id TEXT NOT NULL, room_id TEXT NOT NULL, category_id TEXT NOT NULL, room_order BIGINT NOT NULL, is_public BOOLEAN NOT NULL, UNIQUE (group_id, category_id, room_id, room_order), CHECK (room_order > 0) );
+CREATE UNIQUE INDEX group_summary_rooms_g_idx ON group_summary_rooms(group_id, room_id, category_id);
+CREATE TABLE group_summary_room_categories ( group_id TEXT NOT NULL, category_id TEXT NOT NULL, cat_order BIGINT NOT NULL, UNIQUE (group_id, category_id, cat_order), CHECK (cat_order > 0) );
+CREATE TABLE group_room_categories ( group_id TEXT NOT NULL, category_id TEXT NOT NULL, profile TEXT NOT NULL, is_public BOOLEAN NOT NULL, UNIQUE (group_id, category_id) );
+CREATE TABLE group_summary_users ( group_id TEXT NOT NULL, user_id TEXT NOT NULL, role_id TEXT NOT NULL, user_order BIGINT NOT NULL, is_public BOOLEAN NOT NULL );
+CREATE INDEX group_summary_users_g_idx ON group_summary_users(group_id);
+CREATE TABLE group_summary_roles ( group_id TEXT NOT NULL, role_id TEXT NOT NULL, role_order BIGINT NOT NULL, UNIQUE (group_id, role_id, role_order), CHECK (role_order > 0) );
+CREATE TABLE group_roles ( group_id TEXT NOT NULL, role_id TEXT NOT NULL, profile TEXT NOT NULL, is_public BOOLEAN NOT NULL, UNIQUE (group_id, role_id) );
+CREATE TABLE group_attestations_renewals ( group_id TEXT NOT NULL, user_id TEXT NOT NULL, valid_until_ms BIGINT NOT NULL );
+CREATE INDEX group_attestations_renewals_g_idx ON group_attestations_renewals(group_id, user_id);
+CREATE INDEX group_attestations_renewals_u_idx ON group_attestations_renewals(user_id);
+CREATE INDEX group_attestations_renewals_v_idx ON group_attestations_renewals(valid_until_ms);
+CREATE TABLE group_attestations_remote ( group_id TEXT NOT NULL, user_id TEXT NOT NULL, valid_until_ms BIGINT NOT NULL, attestation_json TEXT NOT NULL );
+CREATE INDEX group_attestations_remote_g_idx ON group_attestations_remote(group_id, user_id);
+CREATE INDEX group_attestations_remote_u_idx ON group_attestations_remote(user_id);
+CREATE INDEX group_attestations_remote_v_idx ON group_attestations_remote(valid_until_ms);
+CREATE TABLE local_group_membership ( group_id TEXT NOT NULL, user_id TEXT NOT NULL, is_admin BOOLEAN NOT NULL, membership TEXT NOT NULL, is_publicised BOOLEAN NOT NULL, content TEXT NOT NULL );
+CREATE INDEX local_group_membership_u_idx ON local_group_membership(user_id, group_id);
+CREATE INDEX local_group_membership_g_idx ON local_group_membership(group_id);
+CREATE TABLE local_group_updates ( stream_id BIGINT NOT NULL, group_id TEXT NOT NULL, user_id TEXT NOT NULL, type TEXT NOT NULL, content TEXT NOT NULL );
+CREATE TABLE remote_profile_cache ( user_id TEXT NOT NULL, displayname TEXT, avatar_url TEXT, last_check BIGINT NOT NULL );
+CREATE UNIQUE INDEX remote_profile_cache_user_id ON remote_profile_cache(user_id);
+CREATE INDEX remote_profile_cache_time ON remote_profile_cache(last_check);
+CREATE TABLE IF NOT EXISTS "deleted_pushers" ( stream_id BIGINT NOT NULL, app_id TEXT NOT NULL, pushkey TEXT NOT NULL, user_id TEXT NOT NULL );
+CREATE INDEX deleted_pushers_stream_id ON deleted_pushers (stream_id);
+CREATE TABLE IF NOT EXISTS "groups" ( group_id TEXT NOT NULL, name TEXT, avatar_url TEXT, short_description TEXT, long_description TEXT, is_public BOOL NOT NULL , join_policy TEXT NOT NULL DEFAULT 'invite');
+CREATE UNIQUE INDEX groups_idx ON groups(group_id);
+CREATE TABLE IF NOT EXISTS "user_directory" ( user_id TEXT NOT NULL, room_id TEXT, display_name TEXT, avatar_url TEXT );
+CREATE INDEX user_directory_room_idx ON user_directory(room_id);
+CREATE UNIQUE INDEX user_directory_user_idx ON user_directory(user_id);
+CREATE TABLE event_push_actions_staging ( event_id TEXT NOT NULL, user_id TEXT NOT NULL, actions TEXT NOT NULL, notif SMALLINT NOT NULL, highlight SMALLINT NOT NULL );
+CREATE INDEX event_push_actions_staging_id ON event_push_actions_staging(event_id);
+CREATE TABLE users_pending_deactivation ( user_id TEXT NOT NULL );
+CREATE UNIQUE INDEX group_invites_g_idx ON group_invites(group_id, user_id);
+CREATE UNIQUE INDEX group_users_g_idx ON group_users(group_id, user_id);
+CREATE INDEX group_users_u_idx ON group_users(user_id);
+CREATE INDEX group_invites_u_idx ON group_invites(user_id);
+CREATE UNIQUE INDEX group_rooms_g_idx ON group_rooms(group_id, room_id);
+CREATE INDEX group_rooms_r_idx ON group_rooms(room_id);
+CREATE TABLE user_daily_visits ( user_id TEXT NOT NULL, device_id TEXT, timestamp BIGINT NOT NULL );
+CREATE INDEX user_daily_visits_uts_idx ON user_daily_visits(user_id, timestamp);
+CREATE INDEX user_daily_visits_ts_idx ON user_daily_visits(timestamp);
+CREATE TABLE erased_users ( user_id TEXT NOT NULL );
+CREATE UNIQUE INDEX erased_users_user ON erased_users(user_id);
+CREATE TABLE monthly_active_users ( user_id TEXT NOT NULL, timestamp BIGINT NOT NULL );
+CREATE UNIQUE INDEX monthly_active_users_users ON monthly_active_users(user_id);
+CREATE INDEX monthly_active_users_time_stamp ON monthly_active_users(timestamp);
+CREATE TABLE IF NOT EXISTS "e2e_room_keys_versions" ( user_id TEXT NOT NULL, version BIGINT NOT NULL, algorithm TEXT NOT NULL, auth_data TEXT NOT NULL, deleted SMALLINT DEFAULT 0 NOT NULL );
+CREATE UNIQUE INDEX e2e_room_keys_versions_idx ON e2e_room_keys_versions(user_id, version);
+CREATE TABLE IF NOT EXISTS "e2e_room_keys" ( user_id TEXT NOT NULL, room_id TEXT NOT NULL, session_id TEXT NOT NULL, version BIGINT NOT NULL, first_message_index INT, forwarded_count INT, is_verified BOOLEAN, session_data TEXT NOT NULL );
+CREATE UNIQUE INDEX e2e_room_keys_idx ON e2e_room_keys(user_id, room_id, session_id);
+CREATE TABLE users_who_share_private_rooms ( user_id TEXT NOT NULL, other_user_id TEXT NOT NULL, room_id TEXT NOT NULL );
+CREATE UNIQUE INDEX users_who_share_private_rooms_u_idx ON users_who_share_private_rooms(user_id, other_user_id, room_id);
+CREATE INDEX users_who_share_private_rooms_r_idx ON users_who_share_private_rooms(room_id);
+CREATE INDEX users_who_share_private_rooms_o_idx ON users_who_share_private_rooms(other_user_id);
+CREATE TABLE user_threepid_id_server ( user_id TEXT NOT NULL, medium TEXT NOT NULL, address TEXT NOT NULL, id_server TEXT NOT NULL );
+CREATE UNIQUE INDEX user_threepid_id_server_idx ON user_threepid_id_server( user_id, medium, address, id_server );
+CREATE TABLE users_in_public_rooms ( user_id TEXT NOT NULL, room_id TEXT NOT NULL );
+CREATE UNIQUE INDEX users_in_public_rooms_u_idx ON users_in_public_rooms(user_id, room_id);
+CREATE TABLE account_validity ( user_id TEXT PRIMARY KEY, expiration_ts_ms BIGINT NOT NULL, email_sent BOOLEAN NOT NULL, renewal_token TEXT );
+CREATE TABLE event_relations ( event_id TEXT NOT NULL, relates_to_id TEXT NOT NULL, relation_type TEXT NOT NULL, aggregation_key TEXT );
+CREATE UNIQUE INDEX event_relations_id ON event_relations(event_id);
+CREATE INDEX event_relations_relates ON event_relations(relates_to_id, relation_type, aggregation_key);
+CREATE TABLE stats_stream_pos ( Lock CHAR(1) NOT NULL DEFAULT 'X' UNIQUE, stream_id BIGINT, CHECK (Lock='X') );
+CREATE TABLE user_stats ( user_id TEXT NOT NULL, ts BIGINT NOT NULL, bucket_size INT NOT NULL, public_rooms INT NOT NULL, private_rooms INT NOT NULL );
+CREATE UNIQUE INDEX user_stats_user_ts ON user_stats(user_id, ts);
+CREATE TABLE room_stats ( room_id TEXT NOT NULL, ts BIGINT NOT NULL, bucket_size INT NOT NULL, current_state_events INT NOT NULL, joined_members INT NOT NULL, invited_members INT NOT NULL, left_members INT NOT NULL, banned_members INT NOT NULL, state_events INT NOT NULL );
+CREATE UNIQUE INDEX room_stats_room_ts ON room_stats(room_id, ts);
+CREATE TABLE room_state ( room_id TEXT NOT NULL, join_rules TEXT, history_visibility TEXT, encryption TEXT, name TEXT, topic TEXT, avatar TEXT, canonical_alias TEXT );
+CREATE UNIQUE INDEX room_state_room ON room_state(room_id);
+CREATE TABLE room_stats_earliest_token ( room_id TEXT NOT NULL, token BIGINT NOT NULL );
+CREATE UNIQUE INDEX room_stats_earliest_token_idx ON room_stats_earliest_token(room_id);
+CREATE INDEX access_tokens_device_id ON access_tokens (user_id, device_id);
+CREATE INDEX user_ips_device_id ON user_ips (user_id, device_id, last_seen);
+CREATE INDEX event_contains_url_index ON events (room_id, topological_ordering, stream_ordering);
+CREATE INDEX event_push_actions_u_highlight ON event_push_actions (user_id, stream_ordering);
+CREATE INDEX event_push_actions_highlights_index ON event_push_actions (user_id, room_id, topological_ordering, stream_ordering);
+CREATE INDEX current_state_events_member_index ON current_state_events (state_key);
+CREATE INDEX device_inbox_stream_id_user_id ON device_inbox (stream_id, user_id);
+CREATE INDEX device_lists_stream_user_id ON device_lists_stream (user_id, device_id);
+CREATE INDEX local_media_repository_url_idx ON local_media_repository (created_ts);
+CREATE INDEX user_ips_last_seen ON user_ips (user_id, last_seen);
+CREATE INDEX user_ips_last_seen_only ON user_ips (last_seen);
+CREATE INDEX users_creation_ts ON users (creation_ts);
+CREATE INDEX event_to_state_groups_sg_index ON event_to_state_groups (state_group);
+CREATE UNIQUE INDEX device_lists_remote_cache_unique_id ON device_lists_remote_cache (user_id, device_id);
+CREATE UNIQUE INDEX device_lists_remote_extremeties_unique_idx ON device_lists_remote_extremeties (user_id);
+CREATE UNIQUE INDEX user_ips_user_token_ip_unique_index ON user_ips (user_id, access_token, ip);
diff --git a/synapse/storage/databases/main/schema/full_schemas/54/stream_positions.sql b/synapse/storage/databases/main/schema/full_schemas/54/stream_positions.sql
new file mode 100644
index 0000000000..91d21b2921
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/54/stream_positions.sql
@@ -0,0 +1,8 @@
+
+INSERT INTO appservice_stream_position (stream_ordering) SELECT COALESCE(MAX(stream_ordering), 0) FROM events;
+INSERT INTO federation_stream_position (type, stream_id) VALUES ('federation', -1);
+INSERT INTO federation_stream_position (type, stream_id) SELECT 'events', coalesce(max(stream_ordering), -1) FROM events;
+INSERT INTO user_directory_stream_pos (stream_id) VALUES (0);
+INSERT INTO stats_stream_pos (stream_id) VALUES (0);
+INSERT INTO event_push_summary_stream_ordering (stream_ordering) VALUES (0);
+-- device_max_stream_id is handled separately in 56/device_stream_id_insert.sql
\ No newline at end of file
diff --git a/synapse/storage/databases/main/schema/full_schemas/README.md b/synapse/storage/databases/main/schema/full_schemas/README.md
new file mode 100644
index 0000000000..c00f287190
--- /dev/null
+++ b/synapse/storage/databases/main/schema/full_schemas/README.md
@@ -0,0 +1,21 @@
+# Synapse Database Schemas
+
+These schemas are used as a basis to create brand new Synapse databases, on both
+SQLite3 and Postgres.
+
+## Building full schema dumps
+
+If you want to recreate these schemas, they need to be made from a database that
+has had all background updates run.
+
+To do so, use `scripts-dev/make_full_schema.sh`. This will produce new
+`full.sql.postgres ` and `full.sql.sqlite` files. 
+
+Ensure postgres is installed and your user has the ability to run bash commands
+such as `createdb`, then call
+
+    ./scripts-dev/make_full_schema.sh -p postgres_username -o output_dir/
+
+There are currently two folders with full-schema snapshots. `16` is a snapshot
+from 2015, for historical reference. The other contains the most recent full
+schema snapshot.
diff --git a/synapse/storage/databases/main/search.py b/synapse/storage/databases/main/search.py
new file mode 100644
index 0000000000..2162d0712d
--- /dev/null
+++ b/synapse/storage/databases/main/search.py
@@ -0,0 +1,710 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015, 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import re
+from collections import namedtuple
+
+from twisted.internet import defer
+
+from synapse.api.errors import SynapseError
+from synapse.storage._base import SQLBaseStore, db_to_json, make_in_list_sql_clause
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.events_worker import EventRedactBehaviour
+from synapse.storage.engines import PostgresEngine, Sqlite3Engine
+
+logger = logging.getLogger(__name__)
+
+SearchEntry = namedtuple(
+    "SearchEntry",
+    ["key", "value", "event_id", "room_id", "stream_ordering", "origin_server_ts"],
+)
+
+
+class SearchWorkerStore(SQLBaseStore):
+    def store_search_entries_txn(self, txn, entries):
+        """Add entries to the search table
+
+        Args:
+            txn (cursor):
+            entries (iterable[SearchEntry]):
+                entries to be added to the table
+        """
+        if not self.hs.config.enable_search:
+            return
+        if isinstance(self.database_engine, PostgresEngine):
+            sql = (
+                "INSERT INTO event_search"
+                " (event_id, room_id, key, vector, stream_ordering, origin_server_ts)"
+                " VALUES (?,?,?,to_tsvector('english', ?),?,?)"
+            )
+
+            args = (
+                (
+                    entry.event_id,
+                    entry.room_id,
+                    entry.key,
+                    entry.value,
+                    entry.stream_ordering,
+                    entry.origin_server_ts,
+                )
+                for entry in entries
+            )
+
+            txn.executemany(sql, args)
+
+        elif isinstance(self.database_engine, Sqlite3Engine):
+            sql = (
+                "INSERT INTO event_search (event_id, room_id, key, value)"
+                " VALUES (?,?,?,?)"
+            )
+            args = (
+                (entry.event_id, entry.room_id, entry.key, entry.value)
+                for entry in entries
+            )
+
+            txn.executemany(sql, args)
+        else:
+            # This should be unreachable.
+            raise Exception("Unrecognized database engine")
+
+
+class SearchBackgroundUpdateStore(SearchWorkerStore):
+
+    EVENT_SEARCH_UPDATE_NAME = "event_search"
+    EVENT_SEARCH_ORDER_UPDATE_NAME = "event_search_order"
+    EVENT_SEARCH_USE_GIST_POSTGRES_NAME = "event_search_postgres_gist"
+    EVENT_SEARCH_USE_GIN_POSTGRES_NAME = "event_search_postgres_gin"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(SearchBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        if not hs.config.enable_search:
+            return
+
+        self.db_pool.updates.register_background_update_handler(
+            self.EVENT_SEARCH_UPDATE_NAME, self._background_reindex_search
+        )
+        self.db_pool.updates.register_background_update_handler(
+            self.EVENT_SEARCH_ORDER_UPDATE_NAME, self._background_reindex_search_order
+        )
+
+        # we used to have a background update to turn the GIN index into a
+        # GIST one; we no longer do that (obviously) because we actually want
+        # a GIN index. However, it's possible that some people might still have
+        # the background update queued, so we register a handler to clear the
+        # background update.
+        self.db_pool.updates.register_noop_background_update(
+            self.EVENT_SEARCH_USE_GIST_POSTGRES_NAME
+        )
+
+        self.db_pool.updates.register_background_update_handler(
+            self.EVENT_SEARCH_USE_GIN_POSTGRES_NAME, self._background_reindex_gin_search
+        )
+
+    @defer.inlineCallbacks
+    def _background_reindex_search(self, progress, batch_size):
+        # we work through the events table from highest stream id to lowest
+        target_min_stream_id = progress["target_min_stream_id_inclusive"]
+        max_stream_id = progress["max_stream_id_exclusive"]
+        rows_inserted = progress.get("rows_inserted", 0)
+
+        TYPES = ["m.room.name", "m.room.message", "m.room.topic"]
+
+        def reindex_search_txn(txn):
+            sql = (
+                "SELECT stream_ordering, event_id, room_id, type, json, "
+                " origin_server_ts FROM events"
+                " JOIN event_json USING (room_id, event_id)"
+                " WHERE ? <= stream_ordering AND stream_ordering < ?"
+                " AND (%s)"
+                " ORDER BY stream_ordering DESC"
+                " LIMIT ?"
+            ) % (" OR ".join("type = '%s'" % (t,) for t in TYPES),)
+
+            txn.execute(sql, (target_min_stream_id, max_stream_id, batch_size))
+
+            # we could stream straight from the results into
+            # store_search_entries_txn with a generator function, but that
+            # would mean having two cursors open on the database at once.
+            # Instead we just build a list of results.
+            rows = self.db_pool.cursor_to_dict(txn)
+            if not rows:
+                return 0
+
+            min_stream_id = rows[-1]["stream_ordering"]
+
+            event_search_rows = []
+            for row in rows:
+                try:
+                    event_id = row["event_id"]
+                    room_id = row["room_id"]
+                    etype = row["type"]
+                    stream_ordering = row["stream_ordering"]
+                    origin_server_ts = row["origin_server_ts"]
+                    try:
+                        event_json = db_to_json(row["json"])
+                        content = event_json["content"]
+                    except Exception:
+                        continue
+
+                    if etype == "m.room.message":
+                        key = "content.body"
+                        value = content["body"]
+                    elif etype == "m.room.topic":
+                        key = "content.topic"
+                        value = content["topic"]
+                    elif etype == "m.room.name":
+                        key = "content.name"
+                        value = content["name"]
+                    else:
+                        raise Exception("unexpected event type %s" % etype)
+                except (KeyError, AttributeError):
+                    # If the event is missing a necessary field then
+                    # skip over it.
+                    continue
+
+                if not isinstance(value, str):
+                    # If the event body, name or topic isn't a string
+                    # then skip over it
+                    continue
+
+                event_search_rows.append(
+                    SearchEntry(
+                        key=key,
+                        value=value,
+                        event_id=event_id,
+                        room_id=room_id,
+                        stream_ordering=stream_ordering,
+                        origin_server_ts=origin_server_ts,
+                    )
+                )
+
+            self.store_search_entries_txn(txn, event_search_rows)
+
+            progress = {
+                "target_min_stream_id_inclusive": target_min_stream_id,
+                "max_stream_id_exclusive": min_stream_id,
+                "rows_inserted": rows_inserted + len(event_search_rows),
+            }
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, self.EVENT_SEARCH_UPDATE_NAME, progress
+            )
+
+            return len(event_search_rows)
+
+        result = yield self.db_pool.runInteraction(
+            self.EVENT_SEARCH_UPDATE_NAME, reindex_search_txn
+        )
+
+        if not result:
+            yield self.db_pool.updates._end_background_update(
+                self.EVENT_SEARCH_UPDATE_NAME
+            )
+
+        return result
+
+    @defer.inlineCallbacks
+    def _background_reindex_gin_search(self, progress, batch_size):
+        """This handles old synapses which used GIST indexes, if any;
+        converting them back to be GIN as per the actual schema.
+        """
+
+        def create_index(conn):
+            conn.rollback()
+
+            # we have to set autocommit, because postgres refuses to
+            # CREATE INDEX CONCURRENTLY without it.
+            conn.set_session(autocommit=True)
+
+            try:
+                c = conn.cursor()
+
+                # if we skipped the conversion to GIST, we may already/still
+                # have an event_search_fts_idx; unfortunately postgres 9.4
+                # doesn't support CREATE INDEX IF EXISTS so we just catch the
+                # exception and ignore it.
+                import psycopg2
+
+                try:
+                    c.execute(
+                        "CREATE INDEX CONCURRENTLY event_search_fts_idx"
+                        " ON event_search USING GIN (vector)"
+                    )
+                except psycopg2.ProgrammingError as e:
+                    logger.warning(
+                        "Ignoring error %r when trying to switch from GIST to GIN", e
+                    )
+
+                # we should now be able to delete the GIST index.
+                c.execute("DROP INDEX IF EXISTS event_search_fts_idx_gist")
+            finally:
+                conn.set_session(autocommit=False)
+
+        if isinstance(self.database_engine, PostgresEngine):
+            yield self.db_pool.runWithConnection(create_index)
+
+        yield self.db_pool.updates._end_background_update(
+            self.EVENT_SEARCH_USE_GIN_POSTGRES_NAME
+        )
+        return 1
+
+    @defer.inlineCallbacks
+    def _background_reindex_search_order(self, progress, batch_size):
+        target_min_stream_id = progress["target_min_stream_id_inclusive"]
+        max_stream_id = progress["max_stream_id_exclusive"]
+        rows_inserted = progress.get("rows_inserted", 0)
+        have_added_index = progress["have_added_indexes"]
+
+        if not have_added_index:
+
+            def create_index(conn):
+                conn.rollback()
+                conn.set_session(autocommit=True)
+                c = conn.cursor()
+
+                # We create with NULLS FIRST so that when we search *backwards*
+                # we get the ones with non null origin_server_ts *first*
+                c.execute(
+                    "CREATE INDEX CONCURRENTLY event_search_room_order ON event_search("
+                    "room_id, origin_server_ts NULLS FIRST, stream_ordering NULLS FIRST)"
+                )
+                c.execute(
+                    "CREATE INDEX CONCURRENTLY event_search_order ON event_search("
+                    "origin_server_ts NULLS FIRST, stream_ordering NULLS FIRST)"
+                )
+                conn.set_session(autocommit=False)
+
+            yield self.db_pool.runWithConnection(create_index)
+
+            pg = dict(progress)
+            pg["have_added_indexes"] = True
+
+            yield self.db_pool.runInteraction(
+                self.EVENT_SEARCH_ORDER_UPDATE_NAME,
+                self.db_pool.updates._background_update_progress_txn,
+                self.EVENT_SEARCH_ORDER_UPDATE_NAME,
+                pg,
+            )
+
+        def reindex_search_txn(txn):
+            sql = (
+                "UPDATE event_search AS es SET stream_ordering = e.stream_ordering,"
+                " origin_server_ts = e.origin_server_ts"
+                " FROM events AS e"
+                " WHERE e.event_id = es.event_id"
+                " AND ? <= e.stream_ordering AND e.stream_ordering < ?"
+                " RETURNING es.stream_ordering"
+            )
+
+            min_stream_id = max_stream_id - batch_size
+            txn.execute(sql, (min_stream_id, max_stream_id))
+            rows = txn.fetchall()
+
+            if min_stream_id < target_min_stream_id:
+                # We've recached the end.
+                return len(rows), False
+
+            progress = {
+                "target_min_stream_id_inclusive": target_min_stream_id,
+                "max_stream_id_exclusive": min_stream_id,
+                "rows_inserted": rows_inserted + len(rows),
+                "have_added_indexes": True,
+            }
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn, self.EVENT_SEARCH_ORDER_UPDATE_NAME, progress
+            )
+
+            return len(rows), True
+
+        num_rows, finished = yield self.db_pool.runInteraction(
+            self.EVENT_SEARCH_ORDER_UPDATE_NAME, reindex_search_txn
+        )
+
+        if not finished:
+            yield self.db_pool.updates._end_background_update(
+                self.EVENT_SEARCH_ORDER_UPDATE_NAME
+            )
+
+        return num_rows
+
+
+class SearchStore(SearchBackgroundUpdateStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(SearchStore, self).__init__(database, db_conn, hs)
+
+    @defer.inlineCallbacks
+    def search_msgs(self, room_ids, search_term, keys):
+        """Performs a full text search over events with given keys.
+
+        Args:
+            room_ids (list): List of room ids to search in
+            search_term (str): Search term to search for
+            keys (list): List of keys to search in, currently supports
+                "content.body", "content.name", "content.topic"
+
+        Returns:
+            list of dicts
+        """
+        clauses = []
+
+        search_query = _parse_query(self.database_engine, search_term)
+
+        args = []
+
+        # Make sure we don't explode because the person is in too many rooms.
+        # We filter the results below regardless.
+        if len(room_ids) < 500:
+            clause, args = make_in_list_sql_clause(
+                self.database_engine, "room_id", room_ids
+            )
+            clauses = [clause]
+
+        local_clauses = []
+        for key in keys:
+            local_clauses.append("key = ?")
+            args.append(key)
+
+        clauses.append("(%s)" % (" OR ".join(local_clauses),))
+
+        count_args = args
+        count_clauses = clauses
+
+        if isinstance(self.database_engine, PostgresEngine):
+            sql = (
+                "SELECT ts_rank_cd(vector, to_tsquery('english', ?)) AS rank,"
+                " room_id, event_id"
+                " FROM event_search"
+                " WHERE vector @@ to_tsquery('english', ?)"
+            )
+            args = [search_query, search_query] + args
+
+            count_sql = (
+                "SELECT room_id, count(*) as count FROM event_search"
+                " WHERE vector @@ to_tsquery('english', ?)"
+            )
+            count_args = [search_query] + count_args
+        elif isinstance(self.database_engine, Sqlite3Engine):
+            sql = (
+                "SELECT rank(matchinfo(event_search)) as rank, room_id, event_id"
+                " FROM event_search"
+                " WHERE value MATCH ?"
+            )
+            args = [search_query] + args
+
+            count_sql = (
+                "SELECT room_id, count(*) as count FROM event_search"
+                " WHERE value MATCH ?"
+            )
+            count_args = [search_term] + count_args
+        else:
+            # This should be unreachable.
+            raise Exception("Unrecognized database engine")
+
+        for clause in clauses:
+            sql += " AND " + clause
+
+        for clause in count_clauses:
+            count_sql += " AND " + clause
+
+        # We add an arbitrary limit here to ensure we don't try to pull the
+        # entire table from the database.
+        sql += " ORDER BY rank DESC LIMIT 500"
+
+        results = yield self.db_pool.execute(
+            "search_msgs", self.db_pool.cursor_to_dict, sql, *args
+        )
+
+        results = list(filter(lambda row: row["room_id"] in room_ids, results))
+
+        # We set redact_behaviour to BLOCK here to prevent redacted events being returned in
+        # search results (which is a data leak)
+        events = yield self.get_events_as_list(
+            [r["event_id"] for r in results],
+            redact_behaviour=EventRedactBehaviour.BLOCK,
+        )
+
+        event_map = {ev.event_id: ev for ev in events}
+
+        highlights = None
+        if isinstance(self.database_engine, PostgresEngine):
+            highlights = yield self._find_highlights_in_postgres(search_query, events)
+
+        count_sql += " GROUP BY room_id"
+
+        count_results = yield self.db_pool.execute(
+            "search_rooms_count", self.db_pool.cursor_to_dict, count_sql, *count_args
+        )
+
+        count = sum(row["count"] for row in count_results if row["room_id"] in room_ids)
+
+        return {
+            "results": [
+                {"event": event_map[r["event_id"]], "rank": r["rank"]}
+                for r in results
+                if r["event_id"] in event_map
+            ],
+            "highlights": highlights,
+            "count": count,
+        }
+
+    @defer.inlineCallbacks
+    def search_rooms(self, room_ids, search_term, keys, limit, pagination_token=None):
+        """Performs a full text search over events with given keys.
+
+        Args:
+            room_id (list): The room_ids to search in
+            search_term (str): Search term to search for
+            keys (list): List of keys to search in, currently supports
+                "content.body", "content.name", "content.topic"
+            pagination_token (str): A pagination token previously returned
+
+        Returns:
+            list of dicts
+        """
+        clauses = []
+
+        search_query = _parse_query(self.database_engine, search_term)
+
+        args = []
+
+        # Make sure we don't explode because the person is in too many rooms.
+        # We filter the results below regardless.
+        if len(room_ids) < 500:
+            clause, args = make_in_list_sql_clause(
+                self.database_engine, "room_id", room_ids
+            )
+            clauses = [clause]
+
+        local_clauses = []
+        for key in keys:
+            local_clauses.append("key = ?")
+            args.append(key)
+
+        clauses.append("(%s)" % (" OR ".join(local_clauses),))
+
+        # take copies of the current args and clauses lists, before adding
+        # pagination clauses to main query.
+        count_args = list(args)
+        count_clauses = list(clauses)
+
+        if pagination_token:
+            try:
+                origin_server_ts, stream = pagination_token.split(",")
+                origin_server_ts = int(origin_server_ts)
+                stream = int(stream)
+            except Exception:
+                raise SynapseError(400, "Invalid pagination token")
+
+            clauses.append(
+                "(origin_server_ts < ?"
+                " OR (origin_server_ts = ? AND stream_ordering < ?))"
+            )
+            args.extend([origin_server_ts, origin_server_ts, stream])
+
+        if isinstance(self.database_engine, PostgresEngine):
+            sql = (
+                "SELECT ts_rank_cd(vector, to_tsquery('english', ?)) as rank,"
+                " origin_server_ts, stream_ordering, room_id, event_id"
+                " FROM event_search"
+                " WHERE vector @@ to_tsquery('english', ?) AND "
+            )
+            args = [search_query, search_query] + args
+
+            count_sql = (
+                "SELECT room_id, count(*) as count FROM event_search"
+                " WHERE vector @@ to_tsquery('english', ?) AND "
+            )
+            count_args = [search_query] + count_args
+        elif isinstance(self.database_engine, Sqlite3Engine):
+            # We use CROSS JOIN here to ensure we use the right indexes.
+            # https://sqlite.org/optoverview.html#crossjoin
+            #
+            # We want to use the full text search index on event_search to
+            # extract all possible matches first, then lookup those matches
+            # in the events table to get the topological ordering. We need
+            # to use the indexes in this order because sqlite refuses to
+            # MATCH unless it uses the full text search index
+            sql = (
+                "SELECT rank(matchinfo) as rank, room_id, event_id,"
+                " origin_server_ts, stream_ordering"
+                " FROM (SELECT key, event_id, matchinfo(event_search) as matchinfo"
+                " FROM event_search"
+                " WHERE value MATCH ?"
+                " )"
+                " CROSS JOIN events USING (event_id)"
+                " WHERE "
+            )
+            args = [search_query] + args
+
+            count_sql = (
+                "SELECT room_id, count(*) as count FROM event_search"
+                " WHERE value MATCH ? AND "
+            )
+            count_args = [search_term] + count_args
+        else:
+            # This should be unreachable.
+            raise Exception("Unrecognized database engine")
+
+        sql += " AND ".join(clauses)
+        count_sql += " AND ".join(count_clauses)
+
+        # We add an arbitrary limit here to ensure we don't try to pull the
+        # entire table from the database.
+        if isinstance(self.database_engine, PostgresEngine):
+            sql += (
+                " ORDER BY origin_server_ts DESC NULLS LAST,"
+                " stream_ordering DESC NULLS LAST LIMIT ?"
+            )
+        elif isinstance(self.database_engine, Sqlite3Engine):
+            sql += " ORDER BY origin_server_ts DESC, stream_ordering DESC LIMIT ?"
+        else:
+            raise Exception("Unrecognized database engine")
+
+        args.append(limit)
+
+        results = yield self.db_pool.execute(
+            "search_rooms", self.db_pool.cursor_to_dict, sql, *args
+        )
+
+        results = list(filter(lambda row: row["room_id"] in room_ids, results))
+
+        # We set redact_behaviour to BLOCK here to prevent redacted events being returned in
+        # search results (which is a data leak)
+        events = yield self.get_events_as_list(
+            [r["event_id"] for r in results],
+            redact_behaviour=EventRedactBehaviour.BLOCK,
+        )
+
+        event_map = {ev.event_id: ev for ev in events}
+
+        highlights = None
+        if isinstance(self.database_engine, PostgresEngine):
+            highlights = yield self._find_highlights_in_postgres(search_query, events)
+
+        count_sql += " GROUP BY room_id"
+
+        count_results = yield self.db_pool.execute(
+            "search_rooms_count", self.db_pool.cursor_to_dict, count_sql, *count_args
+        )
+
+        count = sum(row["count"] for row in count_results if row["room_id"] in room_ids)
+
+        return {
+            "results": [
+                {
+                    "event": event_map[r["event_id"]],
+                    "rank": r["rank"],
+                    "pagination_token": "%s,%s"
+                    % (r["origin_server_ts"], r["stream_ordering"]),
+                }
+                for r in results
+                if r["event_id"] in event_map
+            ],
+            "highlights": highlights,
+            "count": count,
+        }
+
+    def _find_highlights_in_postgres(self, search_query, events):
+        """Given a list of events and a search term, return a list of words
+        that match from the content of the event.
+
+        This is used to give a list of words that clients can match against to
+        highlight the matching parts.
+
+        Args:
+            search_query (str)
+            events (list): A list of events
+
+        Returns:
+            deferred : A set of strings.
+        """
+
+        def f(txn):
+            highlight_words = set()
+            for event in events:
+                # As a hack we simply join values of all possible keys. This is
+                # fine since we're only using them to find possible highlights.
+                values = []
+                for key in ("body", "name", "topic"):
+                    v = event.content.get(key, None)
+                    if v:
+                        values.append(v)
+
+                if not values:
+                    continue
+
+                value = " ".join(values)
+
+                # We need to find some values for StartSel and StopSel that
+                # aren't in the value so that we can pick results out.
+                start_sel = "<"
+                stop_sel = ">"
+
+                while start_sel in value:
+                    start_sel += "<"
+                while stop_sel in value:
+                    stop_sel += ">"
+
+                query = "SELECT ts_headline(?, to_tsquery('english', ?), %s)" % (
+                    _to_postgres_options(
+                        {
+                            "StartSel": start_sel,
+                            "StopSel": stop_sel,
+                            "MaxFragments": "50",
+                        }
+                    )
+                )
+                txn.execute(query, (value, search_query))
+                (headline,) = txn.fetchall()[0]
+
+                # Now we need to pick the possible highlights out of the haedline
+                # result.
+                matcher_regex = "%s(.*?)%s" % (
+                    re.escape(start_sel),
+                    re.escape(stop_sel),
+                )
+
+                res = re.findall(matcher_regex, headline)
+                highlight_words.update([r.lower() for r in res])
+
+            return highlight_words
+
+        return self.db_pool.runInteraction("_find_highlights", f)
+
+
+def _to_postgres_options(options_dict):
+    return "'%s'" % (",".join("%s=%s" % (k, v) for k, v in options_dict.items()),)
+
+
+def _parse_query(database_engine, search_term):
+    """Takes a plain unicode string from the user and converts it into a form
+    that can be passed to database.
+    We use this so that we can add prefix matching, which isn't something
+    that is supported by default.
+    """
+
+    # Pull out the individual words, discarding any non-word characters.
+    results = re.findall(r"([\w\-]+)", search_term, re.UNICODE)
+
+    if isinstance(database_engine, PostgresEngine):
+        return " & ".join(result + ":*" for result in results)
+    elif isinstance(database_engine, Sqlite3Engine):
+        return " & ".join(result + "*" for result in results)
+    else:
+        # This should be unreachable.
+        raise Exception("Unrecognized database engine")
diff --git a/synapse/storage/databases/main/signatures.py b/synapse/storage/databases/main/signatures.py
new file mode 100644
index 0000000000..dae8e8bd29
--- /dev/null
+++ b/synapse/storage/databases/main/signatures.py
@@ -0,0 +1,71 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from unpaddedbase64 import encode_base64
+
+from twisted.internet import defer
+
+from synapse.storage._base import SQLBaseStore
+from synapse.util.caches.descriptors import cached, cachedList
+
+
+class SignatureWorkerStore(SQLBaseStore):
+    @cached()
+    def get_event_reference_hash(self, event_id):
+        # This is a dummy function to allow get_event_reference_hashes
+        # to use its cache
+        raise NotImplementedError()
+
+    @cachedList(
+        cached_method_name="get_event_reference_hash", list_name="event_ids", num_args=1
+    )
+    def get_event_reference_hashes(self, event_ids):
+        def f(txn):
+            return {
+                event_id: self._get_event_reference_hashes_txn(txn, event_id)
+                for event_id in event_ids
+            }
+
+        return self.db_pool.runInteraction("get_event_reference_hashes", f)
+
+    @defer.inlineCallbacks
+    def add_event_hashes(self, event_ids):
+        hashes = yield self.get_event_reference_hashes(event_ids)
+        hashes = {
+            e_id: {k: encode_base64(v) for k, v in h.items() if k == "sha256"}
+            for e_id, h in hashes.items()
+        }
+
+        return list(hashes.items())
+
+    def _get_event_reference_hashes_txn(self, txn, event_id):
+        """Get all the hashes for a given PDU.
+        Args:
+            txn (cursor):
+            event_id (str): Id for the Event.
+        Returns:
+            A dict[unicode, bytes] of algorithm -> hash.
+        """
+        query = (
+            "SELECT algorithm, hash"
+            " FROM event_reference_hashes"
+            " WHERE event_id = ?"
+        )
+        txn.execute(query, (event_id,))
+        return {k: v for k, v in txn}
+
+
+class SignatureStore(SignatureWorkerStore):
+    """Persistence for event signatures and hashes"""
diff --git a/synapse/storage/databases/main/state.py b/synapse/storage/databases/main/state.py
new file mode 100644
index 0000000000..96e0378e50
--- /dev/null
+++ b/synapse/storage/databases/main/state.py
@@ -0,0 +1,509 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2020 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+import collections.abc
+import logging
+from collections import namedtuple
+from typing import Iterable, Optional, Set
+
+from synapse.api.constants import EventTypes, Membership
+from synapse.api.errors import NotFoundError, UnsupportedRoomVersionError
+from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, RoomVersion
+from synapse.events import EventBase
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.events_worker import EventsWorkerStore
+from synapse.storage.databases.main.roommember import RoomMemberWorkerStore
+from synapse.storage.state import StateFilter
+from synapse.util.caches import intern_string
+from synapse.util.caches.descriptors import cached, cachedList
+
+logger = logging.getLogger(__name__)
+
+
+MAX_STATE_DELTA_HOPS = 100
+
+
+class _GetStateGroupDelta(
+    namedtuple("_GetStateGroupDelta", ("prev_group", "delta_ids"))
+):
+    """Return type of get_state_group_delta that implements __len__, which lets
+    us use the itrable flag when caching
+    """
+
+    __slots__ = []
+
+    def __len__(self):
+        return len(self.delta_ids) if self.delta_ids else 0
+
+
+# this inherits from EventsWorkerStore because it calls self.get_events
+class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
+    """The parts of StateGroupStore that can be called from workers.
+    """
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(StateGroupWorkerStore, self).__init__(database, db_conn, hs)
+
+    async def get_room_version(self, room_id: str) -> RoomVersion:
+        """Get the room_version of a given room
+
+        Raises:
+            NotFoundError: if the room is unknown
+
+            UnsupportedRoomVersionError: if the room uses an unknown room version.
+                Typically this happens if support for the room's version has been
+                removed from Synapse.
+        """
+        room_version_id = await self.get_room_version_id(room_id)
+        v = KNOWN_ROOM_VERSIONS.get(room_version_id)
+
+        if not v:
+            raise UnsupportedRoomVersionError(
+                "Room %s uses a room version %s which is no longer supported"
+                % (room_id, room_version_id)
+            )
+
+        return v
+
+    @cached(max_entries=10000)
+    async def get_room_version_id(self, room_id: str) -> str:
+        """Get the room_version of a given room
+
+        Raises:
+            NotFoundError: if the room is unknown
+        """
+
+        # First we try looking up room version from the database, but for old
+        # rooms we might not have added the room version to it yet so we fall
+        # back to previous behaviour and look in current state events.
+
+        # We really should have an entry in the rooms table for every room we
+        # care about, but let's be a bit paranoid (at least while the background
+        # update is happening) to avoid breaking existing rooms.
+        version = await self.db_pool.simple_select_one_onecol(
+            table="rooms",
+            keyvalues={"room_id": room_id},
+            retcol="room_version",
+            desc="get_room_version",
+            allow_none=True,
+        )
+
+        if version is not None:
+            return version
+
+        # Retrieve the room's create event
+        create_event = await self.get_create_event_for_room(room_id)
+        return create_event.content.get("room_version", "1")
+
+    async def get_room_predecessor(self, room_id: str) -> Optional[dict]:
+        """Get the predecessor of an upgraded room if it exists.
+        Otherwise return None.
+
+        Args:
+            room_id: The room ID.
+
+        Returns:
+            A dictionary containing the structure of the predecessor
+            field from the room's create event. The structure is subject to other servers,
+            but it is expected to be:
+                * room_id (str): The room ID of the predecessor room
+                * event_id (str): The ID of the tombstone event in the predecessor room
+
+            None if a predecessor key is not found, or is not a dictionary.
+
+        Raises:
+            NotFoundError if the given room is unknown
+        """
+        # Retrieve the room's create event
+        create_event = await self.get_create_event_for_room(room_id)
+
+        # Retrieve the predecessor key of the create event
+        predecessor = create_event.content.get("predecessor", None)
+
+        # Ensure the key is a dictionary
+        if not isinstance(predecessor, collections.abc.Mapping):
+            return None
+
+        return predecessor
+
+    async def get_create_event_for_room(self, room_id: str) -> EventBase:
+        """Get the create state event for a room.
+
+        Args:
+            room_id: The room ID.
+
+        Returns:
+            The room creation event.
+
+        Raises:
+            NotFoundError if the room is unknown
+        """
+        state_ids = await self.get_current_state_ids(room_id)
+        create_id = state_ids.get((EventTypes.Create, ""))
+
+        # If we can't find the create event, assume we've hit a dead end
+        if not create_id:
+            raise NotFoundError("Unknown room %s" % (room_id,))
+
+        # Retrieve the room's create event and return
+        create_event = await self.get_event(create_id)
+        return create_event
+
+    @cached(max_entries=100000, iterable=True)
+    def get_current_state_ids(self, room_id):
+        """Get the current state event ids for a room based on the
+        current_state_events table.
+
+        Args:
+            room_id (str)
+
+        Returns:
+            deferred: dict of (type, state_key) -> event_id
+        """
+
+        def _get_current_state_ids_txn(txn):
+            txn.execute(
+                """SELECT type, state_key, event_id FROM current_state_events
+                WHERE room_id = ?
+                """,
+                (room_id,),
+            )
+
+            return {(intern_string(r[0]), intern_string(r[1])): r[2] for r in txn}
+
+        return self.db_pool.runInteraction(
+            "get_current_state_ids", _get_current_state_ids_txn
+        )
+
+    # FIXME: how should this be cached?
+    def get_filtered_current_state_ids(
+        self, room_id: str, state_filter: StateFilter = StateFilter.all()
+    ):
+        """Get the current state event of a given type for a room based on the
+        current_state_events table.  This may not be as up-to-date as the result
+        of doing a fresh state resolution as per state_handler.get_current_state
+
+        Args:
+            room_id
+            state_filter: The state filter used to fetch state
+                from the database.
+
+        Returns:
+            defer.Deferred[StateMap[str]]: Map from type/state_key to event ID.
+        """
+
+        where_clause, where_args = state_filter.make_sql_filter_clause()
+
+        if not where_clause:
+            # We delegate to the cached version
+            return self.get_current_state_ids(room_id)
+
+        def _get_filtered_current_state_ids_txn(txn):
+            results = {}
+            sql = """
+                SELECT type, state_key, event_id FROM current_state_events
+                WHERE room_id = ?
+            """
+
+            if where_clause:
+                sql += " AND (%s)" % (where_clause,)
+
+            args = [room_id]
+            args.extend(where_args)
+            txn.execute(sql, args)
+            for row in txn:
+                typ, state_key, event_id = row
+                key = (intern_string(typ), intern_string(state_key))
+                results[key] = event_id
+
+            return results
+
+        return self.db_pool.runInteraction(
+            "get_filtered_current_state_ids", _get_filtered_current_state_ids_txn
+        )
+
+    async def get_canonical_alias_for_room(self, room_id: str) -> Optional[str]:
+        """Get canonical alias for room, if any
+
+        Args:
+            room_id: The room ID
+
+        Returns:
+            The canonical alias, if any
+        """
+
+        state = await self.get_filtered_current_state_ids(
+            room_id, StateFilter.from_types([(EventTypes.CanonicalAlias, "")])
+        )
+
+        event_id = state.get((EventTypes.CanonicalAlias, ""))
+        if not event_id:
+            return
+
+        event = await self.get_event(event_id, allow_none=True)
+        if not event:
+            return
+
+        return event.content.get("canonical_alias")
+
+    @cached(max_entries=50000)
+    def _get_state_group_for_event(self, event_id):
+        return self.db_pool.simple_select_one_onecol(
+            table="event_to_state_groups",
+            keyvalues={"event_id": event_id},
+            retcol="state_group",
+            allow_none=True,
+            desc="_get_state_group_for_event",
+        )
+
+    @cachedList(
+        cached_method_name="_get_state_group_for_event",
+        list_name="event_ids",
+        num_args=1,
+        inlineCallbacks=True,
+    )
+    def _get_state_group_for_events(self, event_ids):
+        """Returns mapping event_id -> state_group
+        """
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="event_to_state_groups",
+            column="event_id",
+            iterable=event_ids,
+            keyvalues={},
+            retcols=("event_id", "state_group"),
+            desc="_get_state_group_for_events",
+        )
+
+        return {row["event_id"]: row["state_group"] for row in rows}
+
+    async def get_referenced_state_groups(
+        self, state_groups: Iterable[int]
+    ) -> Set[int]:
+        """Check if the state groups are referenced by events.
+
+        Args:
+            state_groups
+
+        Returns:
+            The subset of state groups that are referenced.
+        """
+
+        rows = await self.db_pool.simple_select_many_batch(
+            table="event_to_state_groups",
+            column="state_group",
+            iterable=state_groups,
+            keyvalues={},
+            retcols=("DISTINCT state_group",),
+            desc="get_referenced_state_groups",
+        )
+
+        return {row["state_group"] for row in rows}
+
+
+class MainStateBackgroundUpdateStore(RoomMemberWorkerStore):
+
+    CURRENT_STATE_INDEX_UPDATE_NAME = "current_state_members_idx"
+    EVENT_STATE_GROUP_INDEX_UPDATE_NAME = "event_to_state_groups_sg_index"
+    DELETE_CURRENT_STATE_UPDATE_NAME = "delete_old_current_state_events"
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(MainStateBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        self.server_name = hs.hostname
+
+        self.db_pool.updates.register_background_index_update(
+            self.CURRENT_STATE_INDEX_UPDATE_NAME,
+            index_name="current_state_events_member_index",
+            table="current_state_events",
+            columns=["state_key"],
+            where_clause="type='m.room.member'",
+        )
+        self.db_pool.updates.register_background_index_update(
+            self.EVENT_STATE_GROUP_INDEX_UPDATE_NAME,
+            index_name="event_to_state_groups_sg_index",
+            table="event_to_state_groups",
+            columns=["state_group"],
+        )
+        self.db_pool.updates.register_background_update_handler(
+            self.DELETE_CURRENT_STATE_UPDATE_NAME, self._background_remove_left_rooms,
+        )
+
+    async def _background_remove_left_rooms(self, progress, batch_size):
+        """Background update to delete rows from `current_state_events` and
+        `event_forward_extremities` tables of rooms that the server is no
+        longer joined to.
+        """
+
+        last_room_id = progress.get("last_room_id", "")
+
+        def _background_remove_left_rooms_txn(txn):
+            # get a batch of room ids to consider
+            sql = """
+                SELECT DISTINCT room_id FROM current_state_events
+                WHERE room_id > ? ORDER BY room_id LIMIT ?
+            """
+
+            txn.execute(sql, (last_room_id, batch_size))
+            room_ids = [row[0] for row in txn]
+            if not room_ids:
+                return True, set()
+
+            ###########################################################################
+            #
+            # exclude rooms where we have active members
+
+            sql = """
+                SELECT room_id
+                FROM local_current_membership
+                WHERE
+                    room_id > ? AND room_id <= ?
+                    AND membership = 'join'
+                GROUP BY room_id
+            """
+
+            txn.execute(sql, (last_room_id, room_ids[-1]))
+            joined_room_ids = {row[0] for row in txn}
+            to_delete = set(room_ids) - joined_room_ids
+
+            ###########################################################################
+            #
+            # exclude rooms which we are in the process of constructing; these otherwise
+            # qualify as "rooms with no local users", and would have their
+            # forward extremities cleaned up.
+
+            # the following query will return a list of rooms which have forward
+            # extremities that are *not* also the create event in the room - ie
+            # those that are not being created currently.
+
+            sql = """
+                SELECT DISTINCT efe.room_id
+                FROM event_forward_extremities efe
+                LEFT JOIN current_state_events cse ON
+                    cse.event_id = efe.event_id
+                    AND cse.type = 'm.room.create'
+                    AND cse.state_key = ''
+                WHERE
+                    cse.event_id IS NULL
+                    AND efe.room_id > ? AND efe.room_id <= ?
+            """
+
+            txn.execute(sql, (last_room_id, room_ids[-1]))
+
+            # build a set of those rooms within `to_delete` that do not appear in
+            # the above, leaving us with the rooms in `to_delete` that *are* being
+            # created.
+            creating_rooms = to_delete.difference(row[0] for row in txn)
+            logger.info("skipping rooms which are being created: %s", creating_rooms)
+
+            # now remove the rooms being created from the list of those to delete.
+            #
+            # (we could have just taken the intersection of `to_delete` with the result
+            # of the sql query, but it's useful to be able to log `creating_rooms`; and
+            # having done so, it's quicker to remove the (few) creating rooms from
+            # `to_delete` than it is to form the intersection with the (larger) list of
+            # not-creating-rooms)
+
+            to_delete -= creating_rooms
+
+            ###########################################################################
+            #
+            # now clear the state for the rooms
+
+            logger.info("Deleting current state left rooms: %r", to_delete)
+
+            # First we get all users that we still think were joined to the
+            # room. This is so that we can mark those device lists as
+            # potentially stale, since there may have been a period where the
+            # server didn't share a room with the remote user and therefore may
+            # have missed any device updates.
+            rows = self.db_pool.simple_select_many_txn(
+                txn,
+                table="current_state_events",
+                column="room_id",
+                iterable=to_delete,
+                keyvalues={"type": EventTypes.Member, "membership": Membership.JOIN},
+                retcols=("state_key",),
+            )
+
+            potentially_left_users = {row["state_key"] for row in rows}
+
+            # Now lets actually delete the rooms from the DB.
+            self.db_pool.simple_delete_many_txn(
+                txn,
+                table="current_state_events",
+                column="room_id",
+                iterable=to_delete,
+                keyvalues={},
+            )
+
+            self.db_pool.simple_delete_many_txn(
+                txn,
+                table="event_forward_extremities",
+                column="room_id",
+                iterable=to_delete,
+                keyvalues={},
+            )
+
+            self.db_pool.updates._background_update_progress_txn(
+                txn,
+                self.DELETE_CURRENT_STATE_UPDATE_NAME,
+                {"last_room_id": room_ids[-1]},
+            )
+
+            return False, potentially_left_users
+
+        finished, potentially_left_users = await self.db_pool.runInteraction(
+            "_background_remove_left_rooms", _background_remove_left_rooms_txn
+        )
+
+        if finished:
+            await self.db_pool.updates._end_background_update(
+                self.DELETE_CURRENT_STATE_UPDATE_NAME
+            )
+
+        # Now go and check if we still share a room with the remote users in
+        # the deleted rooms. If not mark their device lists as stale.
+        joined_users = await self.get_users_server_still_shares_room_with(
+            potentially_left_users
+        )
+
+        for user_id in potentially_left_users - joined_users:
+            await self.mark_remote_user_device_list_as_unsubscribed(user_id)
+
+        return batch_size
+
+
+class StateStore(StateGroupWorkerStore, MainStateBackgroundUpdateStore):
+    """ Keeps track of the state at a given event.
+
+    This is done by the concept of `state groups`. Every event is a assigned
+    a state group (identified by an arbitrary string), which references a
+    collection of state events. The current state of an event is then the
+    collection of state events referenced by the event's state group.
+
+    Hence, every change in the current state causes a new state group to be
+    generated. However, if no change happens (e.g., if we get a message event
+    with only one parent it inherits the state group from its parent.)
+
+    There are three tables:
+      * `state_groups`: Stores group name, first event with in the group and
+        room id.
+      * `event_to_state_groups`: Maps events to state groups.
+      * `state_groups_state`: Maps state group to state events.
+    """
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(StateStore, self).__init__(database, db_conn, hs)
diff --git a/synapse/storage/databases/main/state_deltas.py b/synapse/storage/databases/main/state_deltas.py
new file mode 100644
index 0000000000..0d963c98ff
--- /dev/null
+++ b/synapse/storage/databases/main/state_deltas.py
@@ -0,0 +1,121 @@
+# -*- coding: utf-8 -*-
+# Copyright 2018 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+
+from twisted.internet import defer
+
+from synapse.storage._base import SQLBaseStore
+
+logger = logging.getLogger(__name__)
+
+
+class StateDeltasStore(SQLBaseStore):
+    def get_current_state_deltas(self, prev_stream_id: int, max_stream_id: int):
+        """Fetch a list of room state changes since the given stream id
+
+        Each entry in the result contains the following fields:
+            - stream_id (int)
+            - room_id (str)
+            - type (str): event type
+            - state_key (str):
+            - event_id (str|None): new event_id for this state key. None if the
+                state has been deleted.
+            - prev_event_id (str|None): previous event_id for this state key. None
+                if it's new state.
+
+        Args:
+            prev_stream_id (int): point to get changes since (exclusive)
+            max_stream_id (int): the point that we know has been correctly persisted
+               - ie, an upper limit to return changes from.
+
+        Returns:
+            Deferred[tuple[int, list[dict]]: A tuple consisting of:
+               - the stream id which these results go up to
+               - list of current_state_delta_stream rows. If it is empty, we are
+                 up to date.
+        """
+        prev_stream_id = int(prev_stream_id)
+
+        # check we're not going backwards
+        assert prev_stream_id <= max_stream_id
+
+        if not self._curr_state_delta_stream_cache.has_any_entity_changed(
+            prev_stream_id
+        ):
+            # if the CSDs haven't changed between prev_stream_id and now, we
+            # know for certain that they haven't changed between prev_stream_id and
+            # max_stream_id.
+            return defer.succeed((max_stream_id, []))
+
+        def get_current_state_deltas_txn(txn):
+            # First we calculate the max stream id that will give us less than
+            # N results.
+            # We arbitarily limit to 100 stream_id entries to ensure we don't
+            # select toooo many.
+            sql = """
+                SELECT stream_id, count(*)
+                FROM current_state_delta_stream
+                WHERE stream_id > ? AND stream_id <= ?
+                GROUP BY stream_id
+                ORDER BY stream_id ASC
+                LIMIT 100
+            """
+            txn.execute(sql, (prev_stream_id, max_stream_id))
+
+            total = 0
+
+            for stream_id, count in txn:
+                total += count
+                if total > 100:
+                    # We arbitarily limit to 100 entries to ensure we don't
+                    # select toooo many.
+                    logger.debug(
+                        "Clipping current_state_delta_stream rows to stream_id %i",
+                        stream_id,
+                    )
+                    clipped_stream_id = stream_id
+                    break
+            else:
+                # if there's no problem, we may as well go right up to the max_stream_id
+                clipped_stream_id = max_stream_id
+
+            # Now actually get the deltas
+            sql = """
+                SELECT stream_id, room_id, type, state_key, event_id, prev_event_id
+                FROM current_state_delta_stream
+                WHERE ? < stream_id AND stream_id <= ?
+                ORDER BY stream_id ASC
+            """
+            txn.execute(sql, (prev_stream_id, clipped_stream_id))
+            return clipped_stream_id, self.db_pool.cursor_to_dict(txn)
+
+        return self.db_pool.runInteraction(
+            "get_current_state_deltas", get_current_state_deltas_txn
+        )
+
+    def _get_max_stream_id_in_current_state_deltas_txn(self, txn):
+        return self.db_pool.simple_select_one_onecol_txn(
+            txn,
+            table="current_state_delta_stream",
+            keyvalues={},
+            retcol="COALESCE(MAX(stream_id), -1)",
+        )
+
+    def get_max_stream_id_in_current_state_deltas(self):
+        return self.db_pool.runInteraction(
+            "get_max_stream_id_in_current_state_deltas",
+            self._get_max_stream_id_in_current_state_deltas_txn,
+        )
diff --git a/synapse/storage/databases/main/stats.py b/synapse/storage/databases/main/stats.py
new file mode 100644
index 0000000000..802c9019b9
--- /dev/null
+++ b/synapse/storage/databases/main/stats.py
@@ -0,0 +1,886 @@
+# -*- coding: utf-8 -*-
+# Copyright 2018, 2019 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from itertools import chain
+from typing import Tuple
+
+from twisted.internet.defer import DeferredLock
+
+from synapse.api.constants import EventTypes, Membership
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.state_deltas import StateDeltasStore
+from synapse.storage.engines import PostgresEngine
+from synapse.util.caches.descriptors import cached
+
+logger = logging.getLogger(__name__)
+
+# these fields track absolutes (e.g. total number of rooms on the server)
+# You can think of these as Prometheus Gauges.
+# You can draw these stats on a line graph.
+# Example: number of users in a room
+ABSOLUTE_STATS_FIELDS = {
+    "room": (
+        "current_state_events",
+        "joined_members",
+        "invited_members",
+        "left_members",
+        "banned_members",
+        "local_users_in_room",
+    ),
+    "user": ("joined_rooms",),
+}
+
+# these fields are per-timeslice and so should be reset to 0 upon a new slice
+# You can draw these stats on a histogram.
+# Example: number of events sent locally during a time slice
+PER_SLICE_FIELDS = {
+    "room": ("total_events", "total_event_bytes"),
+    "user": ("invites_sent", "rooms_created", "total_events", "total_event_bytes"),
+}
+
+TYPE_TO_TABLE = {"room": ("room_stats", "room_id"), "user": ("user_stats", "user_id")}
+
+# these are the tables (& ID columns) which contain our actual subjects
+TYPE_TO_ORIGIN_TABLE = {"room": ("rooms", "room_id"), "user": ("users", "name")}
+
+
+class StatsStore(StateDeltasStore):
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(StatsStore, self).__init__(database, db_conn, hs)
+
+        self.server_name = hs.hostname
+        self.clock = self.hs.get_clock()
+        self.stats_enabled = hs.config.stats_enabled
+        self.stats_bucket_size = hs.config.stats_bucket_size
+
+        self.stats_delta_processing_lock = DeferredLock()
+
+        self.db_pool.updates.register_background_update_handler(
+            "populate_stats_process_rooms", self._populate_stats_process_rooms
+        )
+        self.db_pool.updates.register_background_update_handler(
+            "populate_stats_process_rooms_2", self._populate_stats_process_rooms_2
+        )
+        self.db_pool.updates.register_background_update_handler(
+            "populate_stats_process_users", self._populate_stats_process_users
+        )
+        # we no longer need to perform clean-up, but we will give ourselves
+        # the potential to reintroduce it in the future – so documentation
+        # will still encourage the use of this no-op handler.
+        self.db_pool.updates.register_noop_background_update("populate_stats_cleanup")
+        self.db_pool.updates.register_noop_background_update("populate_stats_prepare")
+
+    def quantise_stats_time(self, ts):
+        """
+        Quantises a timestamp to be a multiple of the bucket size.
+
+        Args:
+            ts (int): the timestamp to quantise, in milliseconds since the Unix
+                Epoch
+
+        Returns:
+            int: a timestamp which
+              - is divisible by the bucket size;
+              - is no later than `ts`; and
+              - is the largest such timestamp.
+        """
+        return (ts // self.stats_bucket_size) * self.stats_bucket_size
+
+    async def _populate_stats_process_users(self, progress, batch_size):
+        """
+        This is a background update which regenerates statistics for users.
+        """
+        if not self.stats_enabled:
+            await self.db_pool.updates._end_background_update(
+                "populate_stats_process_users"
+            )
+            return 1
+
+        last_user_id = progress.get("last_user_id", "")
+
+        def _get_next_batch(txn):
+            sql = """
+                    SELECT DISTINCT name FROM users
+                    WHERE name > ?
+                    ORDER BY name ASC
+                    LIMIT ?
+                """
+            txn.execute(sql, (last_user_id, batch_size))
+            return [r for r, in txn]
+
+        users_to_work_on = await self.db_pool.runInteraction(
+            "_populate_stats_process_users", _get_next_batch
+        )
+
+        # No more rooms -- complete the transaction.
+        if not users_to_work_on:
+            await self.db_pool.updates._end_background_update(
+                "populate_stats_process_users"
+            )
+            return 1
+
+        for user_id in users_to_work_on:
+            await self._calculate_and_set_initial_state_for_user(user_id)
+            progress["last_user_id"] = user_id
+
+        await self.db_pool.runInteraction(
+            "populate_stats_process_users",
+            self.db_pool.updates._background_update_progress_txn,
+            "populate_stats_process_users",
+            progress,
+        )
+
+        return len(users_to_work_on)
+
+    async def _populate_stats_process_rooms(self, progress, batch_size):
+        """
+        This was a background update which regenerated statistics for rooms.
+
+        It has been replaced by StatsStore._populate_stats_process_rooms_2. This background
+        job has been scheduled to run as part of Synapse v1.0.0, and again now. To ensure
+        someone upgrading from <v1.0.0, this background task has been turned into a no-op
+        so that the potentially expensive task is not run twice.
+
+        Further context: https://github.com/matrix-org/synapse/pull/7977
+        """
+        await self.db_pool.updates._end_background_update(
+            "populate_stats_process_rooms"
+        )
+        return 1
+
+    async def _populate_stats_process_rooms_2(self, progress, batch_size):
+        """
+        This is a background update which regenerates statistics for rooms.
+
+        It replaces StatsStore._populate_stats_process_rooms. See its docstring for the
+        reasoning.
+        """
+        if not self.stats_enabled:
+            await self.db_pool.updates._end_background_update(
+                "populate_stats_process_rooms_2"
+            )
+            return 1
+
+        last_room_id = progress.get("last_room_id", "")
+
+        def _get_next_batch(txn):
+            sql = """
+                    SELECT DISTINCT room_id FROM current_state_events
+                    WHERE room_id > ?
+                    ORDER BY room_id ASC
+                    LIMIT ?
+                """
+            txn.execute(sql, (last_room_id, batch_size))
+            return [r for r, in txn]
+
+        rooms_to_work_on = await self.db_pool.runInteraction(
+            "populate_stats_rooms_2_get_batch", _get_next_batch
+        )
+
+        # No more rooms -- complete the transaction.
+        if not rooms_to_work_on:
+            await self.db_pool.updates._end_background_update(
+                "populate_stats_process_rooms_2"
+            )
+            return 1
+
+        for room_id in rooms_to_work_on:
+            await self._calculate_and_set_initial_state_for_room(room_id)
+            progress["last_room_id"] = room_id
+
+        await self.db_pool.runInteraction(
+            "_populate_stats_process_rooms_2",
+            self.db_pool.updates._background_update_progress_txn,
+            "populate_stats_process_rooms_2",
+            progress,
+        )
+
+        return len(rooms_to_work_on)
+
+    def get_stats_positions(self):
+        """
+        Returns the stats processor positions.
+        """
+        return self.db_pool.simple_select_one_onecol(
+            table="stats_incremental_position",
+            keyvalues={},
+            retcol="stream_id",
+            desc="stats_incremental_position",
+        )
+
+    def update_room_state(self, room_id, fields):
+        """
+        Args:
+            room_id (str)
+            fields (dict[str:Any])
+        """
+
+        # For whatever reason some of the fields may contain null bytes, which
+        # postgres isn't a fan of, so we replace those fields with null.
+        for col in (
+            "join_rules",
+            "history_visibility",
+            "encryption",
+            "name",
+            "topic",
+            "avatar",
+            "canonical_alias",
+        ):
+            field = fields.get(col)
+            if field and "\0" in field:
+                fields[col] = None
+
+        return self.db_pool.simple_upsert(
+            table="room_stats_state",
+            keyvalues={"room_id": room_id},
+            values=fields,
+            desc="update_room_state",
+        )
+
+    def get_statistics_for_subject(self, stats_type, stats_id, start, size=100):
+        """
+        Get statistics for a given subject.
+
+        Args:
+            stats_type (str): The type of subject
+            stats_id (str): The ID of the subject (e.g. room_id or user_id)
+            start (int): Pagination start. Number of entries, not timestamp.
+            size (int): How many entries to return.
+
+        Returns:
+            Deferred[list[dict]], where the dict has the keys of
+            ABSOLUTE_STATS_FIELDS[stats_type],  and "bucket_size" and "end_ts".
+        """
+        return self.db_pool.runInteraction(
+            "get_statistics_for_subject",
+            self._get_statistics_for_subject_txn,
+            stats_type,
+            stats_id,
+            start,
+            size,
+        )
+
+    def _get_statistics_for_subject_txn(
+        self, txn, stats_type, stats_id, start, size=100
+    ):
+        """
+        Transaction-bound version of L{get_statistics_for_subject}.
+        """
+
+        table, id_col = TYPE_TO_TABLE[stats_type]
+        selected_columns = list(
+            ABSOLUTE_STATS_FIELDS[stats_type] + PER_SLICE_FIELDS[stats_type]
+        )
+
+        slice_list = self.db_pool.simple_select_list_paginate_txn(
+            txn,
+            table + "_historical",
+            "end_ts",
+            start,
+            size,
+            retcols=selected_columns + ["bucket_size", "end_ts"],
+            keyvalues={id_col: stats_id},
+            order_direction="DESC",
+        )
+
+        return slice_list
+
+    @cached()
+    def get_earliest_token_for_stats(self, stats_type, id):
+        """
+        Fetch the "earliest token". This is used by the room stats delta
+        processor to ignore deltas that have been processed between the
+        start of the background task and any particular room's stats
+        being calculated.
+
+        Returns:
+            Deferred[int]
+        """
+        table, id_col = TYPE_TO_TABLE[stats_type]
+
+        return self.db_pool.simple_select_one_onecol(
+            "%s_current" % (table,),
+            keyvalues={id_col: id},
+            retcol="completed_delta_stream_id",
+            allow_none=True,
+        )
+
+    def bulk_update_stats_delta(self, ts, updates, stream_id):
+        """Bulk update stats tables for a given stream_id and updates the stats
+        incremental position.
+
+        Args:
+            ts (int): Current timestamp in ms
+            updates(dict[str, dict[str, dict[str, Counter]]]): The updates to
+                commit as a mapping stats_type -> stats_id -> field -> delta.
+            stream_id (int): Current position.
+
+        Returns:
+            Deferred
+        """
+
+        def _bulk_update_stats_delta_txn(txn):
+            for stats_type, stats_updates in updates.items():
+                for stats_id, fields in stats_updates.items():
+                    logger.debug(
+                        "Updating %s stats for %s: %s", stats_type, stats_id, fields
+                    )
+                    self._update_stats_delta_txn(
+                        txn,
+                        ts=ts,
+                        stats_type=stats_type,
+                        stats_id=stats_id,
+                        fields=fields,
+                        complete_with_stream_id=stream_id,
+                    )
+
+            self.db_pool.simple_update_one_txn(
+                txn,
+                table="stats_incremental_position",
+                keyvalues={},
+                updatevalues={"stream_id": stream_id},
+            )
+
+        return self.db_pool.runInteraction(
+            "bulk_update_stats_delta", _bulk_update_stats_delta_txn
+        )
+
+    def update_stats_delta(
+        self,
+        ts,
+        stats_type,
+        stats_id,
+        fields,
+        complete_with_stream_id,
+        absolute_field_overrides=None,
+    ):
+        """
+        Updates the statistics for a subject, with a delta (difference/relative
+        change).
+
+        Args:
+            ts (int): timestamp of the change
+            stats_type (str): "room" or "user" – the kind of subject
+            stats_id (str): the subject's ID (room ID or user ID)
+            fields (dict[str, int]): Deltas of stats values.
+            complete_with_stream_id (int, optional):
+                If supplied, converts an incomplete row into a complete row,
+                with the supplied stream_id marked as the stream_id where the
+                row was completed.
+            absolute_field_overrides (dict[str, int]): Current stats values
+                (i.e. not deltas) of absolute fields.
+                Does not work with per-slice fields.
+        """
+
+        return self.db_pool.runInteraction(
+            "update_stats_delta",
+            self._update_stats_delta_txn,
+            ts,
+            stats_type,
+            stats_id,
+            fields,
+            complete_with_stream_id=complete_with_stream_id,
+            absolute_field_overrides=absolute_field_overrides,
+        )
+
+    def _update_stats_delta_txn(
+        self,
+        txn,
+        ts,
+        stats_type,
+        stats_id,
+        fields,
+        complete_with_stream_id,
+        absolute_field_overrides=None,
+    ):
+        if absolute_field_overrides is None:
+            absolute_field_overrides = {}
+
+        table, id_col = TYPE_TO_TABLE[stats_type]
+
+        quantised_ts = self.quantise_stats_time(int(ts))
+        end_ts = quantised_ts + self.stats_bucket_size
+
+        # Lets be paranoid and check that all the given field names are known
+        abs_field_names = ABSOLUTE_STATS_FIELDS[stats_type]
+        slice_field_names = PER_SLICE_FIELDS[stats_type]
+        for field in chain(fields.keys(), absolute_field_overrides.keys()):
+            if field not in abs_field_names and field not in slice_field_names:
+                # guard against potential SQL injection dodginess
+                raise ValueError(
+                    "%s is not a recognised field"
+                    " for stats type %s" % (field, stats_type)
+                )
+
+        # Per slice fields do not get added to the _current table
+
+        # This calculates the deltas (`field = field + ?` values)
+        # for absolute fields,
+        # * defaulting to 0 if not specified
+        #     (required for the INSERT part of upserting to work)
+        # * omitting overrides specified in `absolute_field_overrides`
+        deltas_of_absolute_fields = {
+            key: fields.get(key, 0)
+            for key in abs_field_names
+            if key not in absolute_field_overrides
+        }
+
+        # Keep the delta stream ID field up to date
+        absolute_field_overrides = absolute_field_overrides.copy()
+        absolute_field_overrides["completed_delta_stream_id"] = complete_with_stream_id
+
+        # first upsert the `_current` table
+        self._upsert_with_additive_relatives_txn(
+            txn=txn,
+            table=table + "_current",
+            keyvalues={id_col: stats_id},
+            absolutes=absolute_field_overrides,
+            additive_relatives=deltas_of_absolute_fields,
+        )
+
+        per_slice_additive_relatives = {
+            key: fields.get(key, 0) for key in slice_field_names
+        }
+        self._upsert_copy_from_table_with_additive_relatives_txn(
+            txn=txn,
+            into_table=table + "_historical",
+            keyvalues={id_col: stats_id},
+            extra_dst_insvalues={"bucket_size": self.stats_bucket_size},
+            extra_dst_keyvalues={"end_ts": end_ts},
+            additive_relatives=per_slice_additive_relatives,
+            src_table=table + "_current",
+            copy_columns=abs_field_names,
+        )
+
+    def _upsert_with_additive_relatives_txn(
+        self, txn, table, keyvalues, absolutes, additive_relatives
+    ):
+        """Used to update values in the stats tables.
+
+        This is basically a slightly convoluted upsert that *adds* to any
+        existing rows.
+
+        Args:
+            txn
+            table (str): Table name
+            keyvalues (dict[str, any]): Row-identifying key values
+            absolutes (dict[str, any]): Absolute (set) fields
+            additive_relatives (dict[str, int]): Fields that will be added onto
+                if existing row present.
+        """
+        if self.database_engine.can_native_upsert:
+            absolute_updates = [
+                "%(field)s = EXCLUDED.%(field)s" % {"field": field}
+                for field in absolutes.keys()
+            ]
+
+            relative_updates = [
+                "%(field)s = EXCLUDED.%(field)s + %(table)s.%(field)s"
+                % {"table": table, "field": field}
+                for field in additive_relatives.keys()
+            ]
+
+            insert_cols = []
+            qargs = []
+
+            for (key, val) in chain(
+                keyvalues.items(), absolutes.items(), additive_relatives.items()
+            ):
+                insert_cols.append(key)
+                qargs.append(val)
+
+            sql = """
+                INSERT INTO %(table)s (%(insert_cols_cs)s)
+                VALUES (%(insert_vals_qs)s)
+                ON CONFLICT (%(key_columns)s) DO UPDATE SET %(updates)s
+            """ % {
+                "table": table,
+                "insert_cols_cs": ", ".join(insert_cols),
+                "insert_vals_qs": ", ".join(
+                    ["?"] * (len(keyvalues) + len(absolutes) + len(additive_relatives))
+                ),
+                "key_columns": ", ".join(keyvalues),
+                "updates": ", ".join(chain(absolute_updates, relative_updates)),
+            }
+
+            txn.execute(sql, qargs)
+        else:
+            self.database_engine.lock_table(txn, table)
+            retcols = list(chain(absolutes.keys(), additive_relatives.keys()))
+            current_row = self.db_pool.simple_select_one_txn(
+                txn, table, keyvalues, retcols, allow_none=True
+            )
+            if current_row is None:
+                merged_dict = {**keyvalues, **absolutes, **additive_relatives}
+                self.db_pool.simple_insert_txn(txn, table, merged_dict)
+            else:
+                for (key, val) in additive_relatives.items():
+                    current_row[key] += val
+                current_row.update(absolutes)
+                self.db_pool.simple_update_one_txn(txn, table, keyvalues, current_row)
+
+    def _upsert_copy_from_table_with_additive_relatives_txn(
+        self,
+        txn,
+        into_table,
+        keyvalues,
+        extra_dst_keyvalues,
+        extra_dst_insvalues,
+        additive_relatives,
+        src_table,
+        copy_columns,
+    ):
+        """Updates the historic stats table with latest updates.
+
+        This involves copying "absolute" fields from the `_current` table, and
+        adding relative fields to any existing values.
+
+        Args:
+             txn: Transaction
+             into_table (str): The destination table to UPSERT the row into
+             keyvalues (dict[str, any]): Row-identifying key values
+             extra_dst_keyvalues (dict[str, any]): Additional keyvalues
+                for `into_table`.
+             extra_dst_insvalues (dict[str, any]): Additional values to insert
+                on new row creation for `into_table`.
+             additive_relatives (dict[str, any]): Fields that will be added onto
+                if existing row present. (Must be disjoint from copy_columns.)
+             src_table (str): The source table to copy from
+             copy_columns (iterable[str]): The list of columns to copy
+        """
+        if self.database_engine.can_native_upsert:
+            ins_columns = chain(
+                keyvalues,
+                copy_columns,
+                additive_relatives,
+                extra_dst_keyvalues,
+                extra_dst_insvalues,
+            )
+            sel_exprs = chain(
+                keyvalues,
+                copy_columns,
+                (
+                    "?"
+                    for _ in chain(
+                        additive_relatives, extra_dst_keyvalues, extra_dst_insvalues
+                    )
+                ),
+            )
+            keyvalues_where = ("%s = ?" % f for f in keyvalues)
+
+            sets_cc = ("%s = EXCLUDED.%s" % (f, f) for f in copy_columns)
+            sets_ar = (
+                "%s = EXCLUDED.%s + %s.%s" % (f, f, into_table, f)
+                for f in additive_relatives
+            )
+
+            sql = """
+                INSERT INTO %(into_table)s (%(ins_columns)s)
+                SELECT %(sel_exprs)s
+                FROM %(src_table)s
+                WHERE %(keyvalues_where)s
+                ON CONFLICT (%(keyvalues)s)
+                DO UPDATE SET %(sets)s
+            """ % {
+                "into_table": into_table,
+                "ins_columns": ", ".join(ins_columns),
+                "sel_exprs": ", ".join(sel_exprs),
+                "keyvalues_where": " AND ".join(keyvalues_where),
+                "src_table": src_table,
+                "keyvalues": ", ".join(
+                    chain(keyvalues.keys(), extra_dst_keyvalues.keys())
+                ),
+                "sets": ", ".join(chain(sets_cc, sets_ar)),
+            }
+
+            qargs = list(
+                chain(
+                    additive_relatives.values(),
+                    extra_dst_keyvalues.values(),
+                    extra_dst_insvalues.values(),
+                    keyvalues.values(),
+                )
+            )
+            txn.execute(sql, qargs)
+        else:
+            self.database_engine.lock_table(txn, into_table)
+            src_row = self.db_pool.simple_select_one_txn(
+                txn, src_table, keyvalues, copy_columns
+            )
+            all_dest_keyvalues = {**keyvalues, **extra_dst_keyvalues}
+            dest_current_row = self.db_pool.simple_select_one_txn(
+                txn,
+                into_table,
+                keyvalues=all_dest_keyvalues,
+                retcols=list(chain(additive_relatives.keys(), copy_columns)),
+                allow_none=True,
+            )
+
+            if dest_current_row is None:
+                merged_dict = {
+                    **keyvalues,
+                    **extra_dst_keyvalues,
+                    **extra_dst_insvalues,
+                    **src_row,
+                    **additive_relatives,
+                }
+                self.db_pool.simple_insert_txn(txn, into_table, merged_dict)
+            else:
+                for (key, val) in additive_relatives.items():
+                    src_row[key] = dest_current_row[key] + val
+                self.db_pool.simple_update_txn(
+                    txn, into_table, all_dest_keyvalues, src_row
+                )
+
+    def get_changes_room_total_events_and_bytes(self, min_pos, max_pos):
+        """Fetches the counts of events in the given range of stream IDs.
+
+        Args:
+            min_pos (int)
+            max_pos (int)
+
+        Returns:
+            Deferred[dict[str, dict[str, int]]]: Mapping of room ID to field
+            changes.
+        """
+
+        return self.db_pool.runInteraction(
+            "stats_incremental_total_events_and_bytes",
+            self.get_changes_room_total_events_and_bytes_txn,
+            min_pos,
+            max_pos,
+        )
+
+    def get_changes_room_total_events_and_bytes_txn(self, txn, low_pos, high_pos):
+        """Gets the total_events and total_event_bytes counts for rooms and
+        senders, in a range of stream_orderings (including backfilled events).
+
+        Args:
+            txn
+            low_pos (int): Low stream ordering
+            high_pos (int): High stream ordering
+
+        Returns:
+            tuple[dict[str, dict[str, int]], dict[str, dict[str, int]]]: The
+            room and user deltas for total_events/total_event_bytes in the
+            format of `stats_id` -> fields
+        """
+
+        if low_pos >= high_pos:
+            # nothing to do here.
+            return {}, {}
+
+        if isinstance(self.database_engine, PostgresEngine):
+            new_bytes_expression = "OCTET_LENGTH(json)"
+        else:
+            new_bytes_expression = "LENGTH(CAST(json AS BLOB))"
+
+        sql = """
+            SELECT events.room_id, COUNT(*) AS new_events, SUM(%s) AS new_bytes
+            FROM events INNER JOIN event_json USING (event_id)
+            WHERE (? < stream_ordering AND stream_ordering <= ?)
+                OR (? <= stream_ordering AND stream_ordering <= ?)
+            GROUP BY events.room_id
+        """ % (
+            new_bytes_expression,
+        )
+
+        txn.execute(sql, (low_pos, high_pos, -high_pos, -low_pos))
+
+        room_deltas = {
+            room_id: {"total_events": new_events, "total_event_bytes": new_bytes}
+            for room_id, new_events, new_bytes in txn
+        }
+
+        sql = """
+            SELECT events.sender, COUNT(*) AS new_events, SUM(%s) AS new_bytes
+            FROM events INNER JOIN event_json USING (event_id)
+            WHERE (? < stream_ordering AND stream_ordering <= ?)
+                OR (? <= stream_ordering AND stream_ordering <= ?)
+            GROUP BY events.sender
+        """ % (
+            new_bytes_expression,
+        )
+
+        txn.execute(sql, (low_pos, high_pos, -high_pos, -low_pos))
+
+        user_deltas = {
+            user_id: {"total_events": new_events, "total_event_bytes": new_bytes}
+            for user_id, new_events, new_bytes in txn
+            if self.hs.is_mine_id(user_id)
+        }
+
+        return room_deltas, user_deltas
+
+    async def _calculate_and_set_initial_state_for_room(
+        self, room_id: str
+    ) -> Tuple[dict, dict, int]:
+        """Calculate and insert an entry into room_stats_current.
+
+        Args:
+            room_id: The room ID under calculation.
+
+        Returns:
+            A tuple of room state, membership counts and stream position.
+        """
+
+        def _fetch_current_state_stats(txn):
+            pos = self.get_room_max_stream_ordering()
+
+            rows = self.db_pool.simple_select_many_txn(
+                txn,
+                table="current_state_events",
+                column="type",
+                iterable=[
+                    EventTypes.Create,
+                    EventTypes.JoinRules,
+                    EventTypes.RoomHistoryVisibility,
+                    EventTypes.RoomEncryption,
+                    EventTypes.Name,
+                    EventTypes.Topic,
+                    EventTypes.RoomAvatar,
+                    EventTypes.CanonicalAlias,
+                ],
+                keyvalues={"room_id": room_id, "state_key": ""},
+                retcols=["event_id"],
+            )
+
+            event_ids = [row["event_id"] for row in rows]
+
+            txn.execute(
+                """
+                    SELECT membership, count(*) FROM current_state_events
+                    WHERE room_id = ? AND type = 'm.room.member'
+                    GROUP BY membership
+                """,
+                (room_id,),
+            )
+            membership_counts = {membership: cnt for membership, cnt in txn}
+
+            txn.execute(
+                """
+                    SELECT COALESCE(count(*), 0) FROM current_state_events
+                    WHERE room_id = ?
+                """,
+                (room_id,),
+            )
+
+            (current_state_events_count,) = txn.fetchone()
+
+            users_in_room = self.get_users_in_room_txn(txn, room_id)
+
+            return (
+                event_ids,
+                membership_counts,
+                current_state_events_count,
+                users_in_room,
+                pos,
+            )
+
+        (
+            event_ids,
+            membership_counts,
+            current_state_events_count,
+            users_in_room,
+            pos,
+        ) = await self.db_pool.runInteraction(
+            "get_initial_state_for_room", _fetch_current_state_stats
+        )
+
+        state_event_map = await self.get_events(event_ids, get_prev_content=False)
+
+        room_state = {
+            "join_rules": None,
+            "history_visibility": None,
+            "encryption": None,
+            "name": None,
+            "topic": None,
+            "avatar": None,
+            "canonical_alias": None,
+            "is_federatable": True,
+        }
+
+        for event in state_event_map.values():
+            if event.type == EventTypes.JoinRules:
+                room_state["join_rules"] = event.content.get("join_rule")
+            elif event.type == EventTypes.RoomHistoryVisibility:
+                room_state["history_visibility"] = event.content.get(
+                    "history_visibility"
+                )
+            elif event.type == EventTypes.RoomEncryption:
+                room_state["encryption"] = event.content.get("algorithm")
+            elif event.type == EventTypes.Name:
+                room_state["name"] = event.content.get("name")
+            elif event.type == EventTypes.Topic:
+                room_state["topic"] = event.content.get("topic")
+            elif event.type == EventTypes.RoomAvatar:
+                room_state["avatar"] = event.content.get("url")
+            elif event.type == EventTypes.CanonicalAlias:
+                room_state["canonical_alias"] = event.content.get("alias")
+            elif event.type == EventTypes.Create:
+                room_state["is_federatable"] = (
+                    event.content.get("m.federate", True) is True
+                )
+
+        await self.update_room_state(room_id, room_state)
+
+        local_users_in_room = [u for u in users_in_room if self.hs.is_mine_id(u)]
+
+        await self.update_stats_delta(
+            ts=self.clock.time_msec(),
+            stats_type="room",
+            stats_id=room_id,
+            fields={},
+            complete_with_stream_id=pos,
+            absolute_field_overrides={
+                "current_state_events": current_state_events_count,
+                "joined_members": membership_counts.get(Membership.JOIN, 0),
+                "invited_members": membership_counts.get(Membership.INVITE, 0),
+                "left_members": membership_counts.get(Membership.LEAVE, 0),
+                "banned_members": membership_counts.get(Membership.BAN, 0),
+                "local_users_in_room": len(local_users_in_room),
+            },
+        )
+
+    async def _calculate_and_set_initial_state_for_user(self, user_id):
+        def _calculate_and_set_initial_state_for_user_txn(txn):
+            pos = self._get_max_stream_id_in_current_state_deltas_txn(txn)
+
+            txn.execute(
+                """
+                SELECT COUNT(distinct room_id) FROM current_state_events
+                    WHERE type = 'm.room.member' AND state_key = ?
+                        AND membership = 'join'
+                """,
+                (user_id,),
+            )
+            (count,) = txn.fetchone()
+            return count, pos
+
+        joined_rooms, pos = await self.db_pool.runInteraction(
+            "calculate_and_set_initial_state_for_user",
+            _calculate_and_set_initial_state_for_user_txn,
+        )
+
+        await self.update_stats_delta(
+            ts=self.clock.time_msec(),
+            stats_type="user",
+            stats_id=user_id,
+            fields={},
+            complete_with_stream_id=pos,
+            absolute_field_overrides={"joined_rooms": joined_rooms},
+        )
diff --git a/synapse/storage/databases/main/stream.py b/synapse/storage/databases/main/stream.py
new file mode 100644
index 0000000000..aaf225894e
--- /dev/null
+++ b/synapse/storage/databases/main/stream.py
@@ -0,0 +1,1064 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2017 Vector Creations Ltd
+# Copyright 2018-2019 New Vector Ltd
+# Copyright 2019 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+""" This module is responsible for getting events from the DB for pagination
+and event streaming.
+
+The order it returns events in depend on whether we are streaming forwards or
+are paginating backwards. We do this because we want to handle out of order
+messages nicely, while still returning them in the correct order when we
+paginate bacwards.
+
+This is implemented by keeping two ordering columns: stream_ordering and
+topological_ordering. Stream ordering is basically insertion/received order
+(except for events from backfill requests). The topological_ordering is a
+weak ordering of events based on the pdu graph.
+
+This means that we have to have two different types of tokens, depending on
+what sort order was used:
+    - stream tokens are of the form: "s%d", which maps directly to the column
+    - topological tokems: "t%d-%d", where the integers map to the topological
+      and stream ordering columns respectively.
+"""
+
+import abc
+import logging
+from collections import namedtuple
+from typing import Optional
+
+from twisted.internet import defer
+
+from synapse.logging.context import make_deferred_yieldable, run_in_background
+from synapse.storage._base import SQLBaseStore
+from synapse.storage.database import DatabasePool, make_in_list_sql_clause
+from synapse.storage.databases.main.events_worker import EventsWorkerStore
+from synapse.storage.engines import PostgresEngine
+from synapse.types import RoomStreamToken
+from synapse.util.caches.stream_change_cache import StreamChangeCache
+
+logger = logging.getLogger(__name__)
+
+
+MAX_STREAM_SIZE = 1000
+
+
+_STREAM_TOKEN = "stream"
+_TOPOLOGICAL_TOKEN = "topological"
+
+
+# Used as return values for pagination APIs
+_EventDictReturn = namedtuple(
+    "_EventDictReturn", ("event_id", "topological_ordering", "stream_ordering")
+)
+
+
+def generate_pagination_where_clause(
+    direction, column_names, from_token, to_token, engine
+):
+    """Creates an SQL expression to bound the columns by the pagination
+    tokens.
+
+    For example creates an SQL expression like:
+
+        (6, 7) >= (topological_ordering, stream_ordering)
+        AND (5, 3) < (topological_ordering, stream_ordering)
+
+    would be generated for dir=b, from_token=(6, 7) and to_token=(5, 3).
+
+    Note that tokens are considered to be after the row they are in, e.g. if
+    a row A has a token T, then we consider A to be before T. This convention
+    is important when figuring out inequalities for the generated SQL, and
+    produces the following result:
+        - If paginating forwards then we exclude any rows matching the from
+          token, but include those that match the to token.
+        - If paginating backwards then we include any rows matching the from
+          token, but include those that match the to token.
+
+    Args:
+        direction (str): Whether we're paginating backwards("b") or
+            forwards ("f").
+        column_names (tuple[str, str]): The column names to bound. Must *not*
+            be user defined as these get inserted directly into the SQL
+            statement without escapes.
+        from_token (tuple[int, int]|None): The start point for the pagination.
+            This is an exclusive minimum bound if direction is "f", and an
+            inclusive maximum bound if direction is "b".
+        to_token (tuple[int, int]|None): The endpoint point for the pagination.
+            This is an inclusive maximum bound if direction is "f", and an
+            exclusive minimum bound if direction is "b".
+        engine: The database engine to generate the clauses for
+
+    Returns:
+        str: The sql expression
+    """
+    assert direction in ("b", "f")
+
+    where_clause = []
+    if from_token:
+        where_clause.append(
+            _make_generic_sql_bound(
+                bound=">=" if direction == "b" else "<",
+                column_names=column_names,
+                values=from_token,
+                engine=engine,
+            )
+        )
+
+    if to_token:
+        where_clause.append(
+            _make_generic_sql_bound(
+                bound="<" if direction == "b" else ">=",
+                column_names=column_names,
+                values=to_token,
+                engine=engine,
+            )
+        )
+
+    return " AND ".join(where_clause)
+
+
+def _make_generic_sql_bound(bound, column_names, values, engine):
+    """Create an SQL expression that bounds the given column names by the
+    values, e.g. create the equivalent of `(1, 2) < (col1, col2)`.
+
+    Only works with two columns.
+
+    Older versions of SQLite don't support that syntax so we have to expand it
+    out manually.
+
+    Args:
+        bound (str): The comparison operator to use. One of ">", "<", ">=",
+            "<=", where the values are on the left and columns on the right.
+        names (tuple[str, str]): The column names. Must *not* be user defined
+            as these get inserted directly into the SQL statement without
+            escapes.
+        values (tuple[int|None, int]): The values to bound the columns by. If
+            the first value is None then only creates a bound on the second
+            column.
+        engine: The database engine to generate the SQL for
+
+    Returns:
+        str
+    """
+
+    assert bound in (">", "<", ">=", "<=")
+
+    name1, name2 = column_names
+    val1, val2 = values
+
+    if val1 is None:
+        val2 = int(val2)
+        return "(%d %s %s)" % (val2, bound, name2)
+
+    val1 = int(val1)
+    val2 = int(val2)
+
+    if isinstance(engine, PostgresEngine):
+        # Postgres doesn't optimise ``(x < a) OR (x=a AND y<b)`` as well
+        # as it optimises ``(x,y) < (a,b)`` on multicolumn indexes. So we
+        # use the later form when running against postgres.
+        return "((%d,%d) %s (%s,%s))" % (val1, val2, bound, name1, name2)
+
+    # We want to generate queries of e.g. the form:
+    #
+    #   (val1 < name1 OR (val1 = name1 AND val2 <= name2))
+    #
+    # which is equivalent to (val1, val2) < (name1, name2)
+
+    return """(
+        {val1:d} {strict_bound} {name1}
+        OR ({val1:d} = {name1} AND {val2:d} {bound} {name2})
+    )""".format(
+        name1=name1,
+        val1=val1,
+        name2=name2,
+        val2=val2,
+        strict_bound=bound[0],  # The first bound must always be strict equality here
+        bound=bound,
+    )
+
+
+def filter_to_clause(event_filter):
+    # NB: This may create SQL clauses that don't optimise well (and we don't
+    # have indices on all possible clauses). E.g. it may create
+    # "room_id == X AND room_id != X", which postgres doesn't optimise.
+
+    if not event_filter:
+        return "", []
+
+    clauses = []
+    args = []
+
+    if event_filter.types:
+        clauses.append("(%s)" % " OR ".join("type = ?" for _ in event_filter.types))
+        args.extend(event_filter.types)
+
+    for typ in event_filter.not_types:
+        clauses.append("type != ?")
+        args.append(typ)
+
+    if event_filter.senders:
+        clauses.append("(%s)" % " OR ".join("sender = ?" for _ in event_filter.senders))
+        args.extend(event_filter.senders)
+
+    for sender in event_filter.not_senders:
+        clauses.append("sender != ?")
+        args.append(sender)
+
+    if event_filter.rooms:
+        clauses.append("(%s)" % " OR ".join("room_id = ?" for _ in event_filter.rooms))
+        args.extend(event_filter.rooms)
+
+    for room_id in event_filter.not_rooms:
+        clauses.append("room_id != ?")
+        args.append(room_id)
+
+    if event_filter.contains_url:
+        clauses.append("contains_url = ?")
+        args.append(event_filter.contains_url)
+
+    # We're only applying the "labels" filter on the database query, because applying the
+    # "not_labels" filter via a SQL query is non-trivial. Instead, we let
+    # event_filter.check_fields apply it, which is not as efficient but makes the
+    # implementation simpler.
+    if event_filter.labels:
+        clauses.append("(%s)" % " OR ".join("label = ?" for _ in event_filter.labels))
+        args.extend(event_filter.labels)
+
+    return " AND ".join(clauses), args
+
+
+class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
+    """This is an abstract base class where subclasses must implement
+    `get_room_max_stream_ordering` and `get_room_min_stream_ordering`
+    which can be called in the initializer.
+    """
+
+    __metaclass__ = abc.ABCMeta
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(StreamWorkerStore, self).__init__(database, db_conn, hs)
+
+        self._instance_name = hs.get_instance_name()
+        self._send_federation = hs.should_send_federation()
+        self._federation_shard_config = hs.config.worker.federation_shard_config
+
+        # If we're a process that sends federation we may need to reset the
+        # `federation_stream_position` table to match the current sharding
+        # config. We don't do this now as otherwise two processes could conflict
+        # during startup which would cause one to die.
+        self._need_to_reset_federation_stream_positions = self._send_federation
+
+        events_max = self.get_room_max_stream_ordering()
+        event_cache_prefill, min_event_val = self.db_pool.get_cache_dict(
+            db_conn,
+            "events",
+            entity_column="room_id",
+            stream_column="stream_ordering",
+            max_value=events_max,
+        )
+        self._events_stream_cache = StreamChangeCache(
+            "EventsRoomStreamChangeCache",
+            min_event_val,
+            prefilled_cache=event_cache_prefill,
+        )
+        self._membership_stream_cache = StreamChangeCache(
+            "MembershipStreamChangeCache", events_max
+        )
+
+        self._stream_order_on_start = self.get_room_max_stream_ordering()
+
+    @abc.abstractmethod
+    def get_room_max_stream_ordering(self):
+        raise NotImplementedError()
+
+    @abc.abstractmethod
+    def get_room_min_stream_ordering(self):
+        raise NotImplementedError()
+
+    @defer.inlineCallbacks
+    def get_room_events_stream_for_rooms(
+        self, room_ids, from_key, to_key, limit=0, order="DESC"
+    ):
+        """Get new room events in stream ordering since `from_key`.
+
+        Args:
+            room_id (str)
+            from_key (str): Token from which no events are returned before
+            to_key (str): Token from which no events are returned after. (This
+                is typically the current stream token)
+            limit (int): Maximum number of events to return
+            order (str): Either "DESC" or "ASC". Determines which events are
+                returned when the result is limited. If "DESC" then the most
+                recent `limit` events are returned, otherwise returns the
+                oldest `limit` events.
+
+        Returns:
+            Deferred[dict[str,tuple[list[FrozenEvent], str]]]
+                A map from room id to a tuple containing:
+                    - list of recent events in the room
+                    - stream ordering key for the start of the chunk of events returned.
+        """
+        from_id = RoomStreamToken.parse_stream_token(from_key).stream
+
+        room_ids = yield self._events_stream_cache.get_entities_changed(
+            room_ids, from_id
+        )
+
+        if not room_ids:
+            return {}
+
+        results = {}
+        room_ids = list(room_ids)
+        for rm_ids in (room_ids[i : i + 20] for i in range(0, len(room_ids), 20)):
+            res = yield make_deferred_yieldable(
+                defer.gatherResults(
+                    [
+                        run_in_background(
+                            self.get_room_events_stream_for_room,
+                            room_id,
+                            from_key,
+                            to_key,
+                            limit,
+                            order=order,
+                        )
+                        for room_id in rm_ids
+                    ],
+                    consumeErrors=True,
+                )
+            )
+            results.update(dict(zip(rm_ids, res)))
+
+        return results
+
+    def get_rooms_that_changed(self, room_ids, from_key):
+        """Given a list of rooms and a token, return rooms where there may have
+        been changes.
+
+        Args:
+            room_ids (list)
+            from_key (str): The room_key portion of a StreamToken
+        """
+        from_key = RoomStreamToken.parse_stream_token(from_key).stream
+        return {
+            room_id
+            for room_id in room_ids
+            if self._events_stream_cache.has_entity_changed(room_id, from_key)
+        }
+
+    @defer.inlineCallbacks
+    def get_room_events_stream_for_room(
+        self, room_id, from_key, to_key, limit=0, order="DESC"
+    ):
+
+        """Get new room events in stream ordering since `from_key`.
+
+        Args:
+            room_id (str)
+            from_key (str): Token from which no events are returned before
+            to_key (str): Token from which no events are returned after. (This
+                is typically the current stream token)
+            limit (int): Maximum number of events to return
+            order (str): Either "DESC" or "ASC". Determines which events are
+                returned when the result is limited. If "DESC" then the most
+                recent `limit` events are returned, otherwise returns the
+                oldest `limit` events.
+
+        Returns:
+            Deferred[tuple[list[FrozenEvent], str]]: Returns the list of
+            events (in ascending order) and the token from the start of
+            the chunk of events returned.
+        """
+        if from_key == to_key:
+            return [], from_key
+
+        from_id = RoomStreamToken.parse_stream_token(from_key).stream
+        to_id = RoomStreamToken.parse_stream_token(to_key).stream
+
+        has_changed = yield self._events_stream_cache.has_entity_changed(
+            room_id, from_id
+        )
+
+        if not has_changed:
+            return [], from_key
+
+        def f(txn):
+            sql = (
+                "SELECT event_id, stream_ordering FROM events WHERE"
+                " room_id = ?"
+                " AND not outlier"
+                " AND stream_ordering > ? AND stream_ordering <= ?"
+                " ORDER BY stream_ordering %s LIMIT ?"
+            ) % (order,)
+            txn.execute(sql, (room_id, from_id, to_id, limit))
+
+            rows = [_EventDictReturn(row[0], None, row[1]) for row in txn]
+            return rows
+
+        rows = yield self.db_pool.runInteraction("get_room_events_stream_for_room", f)
+
+        ret = yield self.get_events_as_list(
+            [r.event_id for r in rows], get_prev_content=True
+        )
+
+        self._set_before_and_after(ret, rows, topo_order=from_id is None)
+
+        if order.lower() == "desc":
+            ret.reverse()
+
+        if rows:
+            key = "s%d" % min(r.stream_ordering for r in rows)
+        else:
+            # Assume we didn't get anything because there was nothing to
+            # get.
+            key = from_key
+
+        return ret, key
+
+    @defer.inlineCallbacks
+    def get_membership_changes_for_user(self, user_id, from_key, to_key):
+        from_id = RoomStreamToken.parse_stream_token(from_key).stream
+        to_id = RoomStreamToken.parse_stream_token(to_key).stream
+
+        if from_key == to_key:
+            return []
+
+        if from_id:
+            has_changed = self._membership_stream_cache.has_entity_changed(
+                user_id, int(from_id)
+            )
+            if not has_changed:
+                return []
+
+        def f(txn):
+            sql = (
+                "SELECT m.event_id, stream_ordering FROM events AS e,"
+                " room_memberships AS m"
+                " WHERE e.event_id = m.event_id"
+                " AND m.user_id = ?"
+                " AND e.stream_ordering > ? AND e.stream_ordering <= ?"
+                " ORDER BY e.stream_ordering ASC"
+            )
+            txn.execute(sql, (user_id, from_id, to_id))
+
+            rows = [_EventDictReturn(row[0], None, row[1]) for row in txn]
+
+            return rows
+
+        rows = yield self.db_pool.runInteraction("get_membership_changes_for_user", f)
+
+        ret = yield self.get_events_as_list(
+            [r.event_id for r in rows], get_prev_content=True
+        )
+
+        self._set_before_and_after(ret, rows, topo_order=False)
+
+        return ret
+
+    @defer.inlineCallbacks
+    def get_recent_events_for_room(self, room_id, limit, end_token):
+        """Get the most recent events in the room in topological ordering.
+
+        Args:
+            room_id (str)
+            limit (int)
+            end_token (str): The stream token representing now.
+
+        Returns:
+            Deferred[tuple[list[FrozenEvent], str]]: Returns a list of
+            events and a token pointing to the start of the returned
+            events.
+            The events returned are in ascending order.
+        """
+
+        rows, token = yield self.get_recent_event_ids_for_room(
+            room_id, limit, end_token
+        )
+
+        events = yield self.get_events_as_list(
+            [r.event_id for r in rows], get_prev_content=True
+        )
+
+        self._set_before_and_after(events, rows)
+
+        return (events, token)
+
+    @defer.inlineCallbacks
+    def get_recent_event_ids_for_room(self, room_id, limit, end_token):
+        """Get the most recent events in the room in topological ordering.
+
+        Args:
+            room_id (str)
+            limit (int)
+            end_token (str): The stream token representing now.
+
+        Returns:
+            Deferred[tuple[list[_EventDictReturn], str]]: Returns a list of
+            _EventDictReturn and a token pointing to the start of the returned
+            events.
+            The events returned are in ascending order.
+        """
+        # Allow a zero limit here, and no-op.
+        if limit == 0:
+            return [], end_token
+
+        end_token = RoomStreamToken.parse(end_token)
+
+        rows, token = yield self.db_pool.runInteraction(
+            "get_recent_event_ids_for_room",
+            self._paginate_room_events_txn,
+            room_id,
+            from_token=end_token,
+            limit=limit,
+        )
+
+        # We want to return the results in ascending order.
+        rows.reverse()
+
+        return rows, token
+
+    def get_room_event_before_stream_ordering(self, room_id, stream_ordering):
+        """Gets details of the first event in a room at or before a stream ordering
+
+        Args:
+            room_id (str):
+            stream_ordering (int):
+
+        Returns:
+            Deferred[(int, int, str)]:
+                (stream ordering, topological ordering, event_id)
+        """
+
+        def _f(txn):
+            sql = (
+                "SELECT stream_ordering, topological_ordering, event_id"
+                " FROM events"
+                " WHERE room_id = ? AND stream_ordering <= ?"
+                " AND NOT outlier"
+                " ORDER BY stream_ordering DESC"
+                " LIMIT 1"
+            )
+            txn.execute(sql, (room_id, stream_ordering))
+            return txn.fetchone()
+
+        return self.db_pool.runInteraction("get_room_event_before_stream_ordering", _f)
+
+    async def get_room_events_max_id(self, room_id: Optional[str] = None) -> str:
+        """Returns the current token for rooms stream.
+
+        By default, it returns the current global stream token. Specifying a
+        `room_id` causes it to return the current room specific topological
+        token.
+        """
+        token = self.get_room_max_stream_ordering()
+        if room_id is None:
+            return "s%d" % (token,)
+        else:
+            topo = await self.db_pool.runInteraction(
+                "_get_max_topological_txn", self._get_max_topological_txn, room_id
+            )
+            return "t%d-%d" % (topo, token)
+
+    def get_stream_token_for_event(self, event_id):
+        """The stream token for an event
+        Args:
+            event_id(str): The id of the event to look up a stream token for.
+        Raises:
+            StoreError if the event wasn't in the database.
+        Returns:
+            A deferred "s%d" stream token.
+        """
+        return self.db_pool.simple_select_one_onecol(
+            table="events", keyvalues={"event_id": event_id}, retcol="stream_ordering"
+        ).addCallback(lambda row: "s%d" % (row,))
+
+    def get_topological_token_for_event(self, event_id):
+        """The stream token for an event
+        Args:
+            event_id(str): The id of the event to look up a stream token for.
+        Raises:
+            StoreError if the event wasn't in the database.
+        Returns:
+            A deferred "t%d-%d" topological token.
+        """
+        return self.db_pool.simple_select_one(
+            table="events",
+            keyvalues={"event_id": event_id},
+            retcols=("stream_ordering", "topological_ordering"),
+            desc="get_topological_token_for_event",
+        ).addCallback(
+            lambda row: "t%d-%d" % (row["topological_ordering"], row["stream_ordering"])
+        )
+
+    def get_max_topological_token(self, room_id, stream_key):
+        """Get the max topological token in a room before the given stream
+        ordering.
+
+        Args:
+            room_id (str)
+            stream_key (int)
+
+        Returns:
+            Deferred[int]
+        """
+        sql = (
+            "SELECT coalesce(max(topological_ordering), 0) FROM events"
+            " WHERE room_id = ? AND stream_ordering < ?"
+        )
+        return self.db_pool.execute(
+            "get_max_topological_token", None, sql, room_id, stream_key
+        ).addCallback(lambda r: r[0][0] if r else 0)
+
+    def _get_max_topological_txn(self, txn, room_id):
+        txn.execute(
+            "SELECT MAX(topological_ordering) FROM events WHERE room_id = ?",
+            (room_id,),
+        )
+
+        rows = txn.fetchall()
+        return rows[0][0] if rows else 0
+
+    @staticmethod
+    def _set_before_and_after(events, rows, topo_order=True):
+        """Inserts ordering information to events' internal metadata from
+        the DB rows.
+
+        Args:
+            events (list[FrozenEvent])
+            rows (list[_EventDictReturn])
+            topo_order (bool): Whether the events were ordered topologically
+                or by stream ordering. If true then all rows should have a non
+                null topological_ordering.
+        """
+        for event, row in zip(events, rows):
+            stream = row.stream_ordering
+            if topo_order and row.topological_ordering:
+                topo = row.topological_ordering
+            else:
+                topo = None
+            internal = event.internal_metadata
+            internal.before = str(RoomStreamToken(topo, stream - 1))
+            internal.after = str(RoomStreamToken(topo, stream))
+            internal.order = (int(topo) if topo else 0, int(stream))
+
+    @defer.inlineCallbacks
+    def get_events_around(
+        self, room_id, event_id, before_limit, after_limit, event_filter=None
+    ):
+        """Retrieve events and pagination tokens around a given event in a
+        room.
+
+        Args:
+            room_id (str)
+            event_id (str)
+            before_limit (int)
+            after_limit (int)
+            event_filter (Filter|None)
+
+        Returns:
+            dict
+        """
+
+        results = yield self.db_pool.runInteraction(
+            "get_events_around",
+            self._get_events_around_txn,
+            room_id,
+            event_id,
+            before_limit,
+            after_limit,
+            event_filter,
+        )
+
+        events_before = yield self.get_events_as_list(
+            list(results["before"]["event_ids"]), get_prev_content=True
+        )
+
+        events_after = yield self.get_events_as_list(
+            list(results["after"]["event_ids"]), get_prev_content=True
+        )
+
+        return {
+            "events_before": events_before,
+            "events_after": events_after,
+            "start": results["before"]["token"],
+            "end": results["after"]["token"],
+        }
+
+    def _get_events_around_txn(
+        self, txn, room_id, event_id, before_limit, after_limit, event_filter
+    ):
+        """Retrieves event_ids and pagination tokens around a given event in a
+        room.
+
+        Args:
+            room_id (str)
+            event_id (str)
+            before_limit (int)
+            after_limit (int)
+            event_filter (Filter|None)
+
+        Returns:
+            dict
+        """
+
+        results = self.db_pool.simple_select_one_txn(
+            txn,
+            "events",
+            keyvalues={"event_id": event_id, "room_id": room_id},
+            retcols=["stream_ordering", "topological_ordering"],
+        )
+
+        # Paginating backwards includes the event at the token, but paginating
+        # forward doesn't.
+        before_token = RoomStreamToken(
+            results["topological_ordering"] - 1, results["stream_ordering"]
+        )
+
+        after_token = RoomStreamToken(
+            results["topological_ordering"], results["stream_ordering"]
+        )
+
+        rows, start_token = self._paginate_room_events_txn(
+            txn,
+            room_id,
+            before_token,
+            direction="b",
+            limit=before_limit,
+            event_filter=event_filter,
+        )
+        events_before = [r.event_id for r in rows]
+
+        rows, end_token = self._paginate_room_events_txn(
+            txn,
+            room_id,
+            after_token,
+            direction="f",
+            limit=after_limit,
+            event_filter=event_filter,
+        )
+        events_after = [r.event_id for r in rows]
+
+        return {
+            "before": {"event_ids": events_before, "token": start_token},
+            "after": {"event_ids": events_after, "token": end_token},
+        }
+
+    @defer.inlineCallbacks
+    def get_all_new_events_stream(self, from_id, current_id, limit):
+        """Get all new events
+
+         Returns all events with from_id < stream_ordering <= current_id.
+
+         Args:
+             from_id (int):  the stream_ordering of the last event we processed
+             current_id (int):  the stream_ordering of the most recently processed event
+             limit (int): the maximum number of events to return
+
+         Returns:
+             Deferred[Tuple[int, list[FrozenEvent]]]: A tuple of (next_id, events), where
+             `next_id` is the next value to pass as `from_id` (it will either be the
+             stream_ordering of the last returned event, or, if fewer than `limit` events
+             were found, `current_id`.
+         """
+
+        def get_all_new_events_stream_txn(txn):
+            sql = (
+                "SELECT e.stream_ordering, e.event_id"
+                " FROM events AS e"
+                " WHERE"
+                " ? < e.stream_ordering AND e.stream_ordering <= ?"
+                " ORDER BY e.stream_ordering ASC"
+                " LIMIT ?"
+            )
+
+            txn.execute(sql, (from_id, current_id, limit))
+            rows = txn.fetchall()
+
+            upper_bound = current_id
+            if len(rows) == limit:
+                upper_bound = rows[-1][0]
+
+            return upper_bound, [row[1] for row in rows]
+
+        upper_bound, event_ids = yield self.db_pool.runInteraction(
+            "get_all_new_events_stream", get_all_new_events_stream_txn
+        )
+
+        events = yield self.get_events_as_list(event_ids)
+
+        return upper_bound, events
+
+    async def get_federation_out_pos(self, typ: str) -> int:
+        if self._need_to_reset_federation_stream_positions:
+            await self.db_pool.runInteraction(
+                "_reset_federation_positions_txn", self._reset_federation_positions_txn
+            )
+            self._need_to_reset_federation_stream_positions = False
+
+        return await self.db_pool.simple_select_one_onecol(
+            table="federation_stream_position",
+            retcol="stream_id",
+            keyvalues={"type": typ, "instance_name": self._instance_name},
+            desc="get_federation_out_pos",
+        )
+
+    async def update_federation_out_pos(self, typ, stream_id):
+        if self._need_to_reset_federation_stream_positions:
+            await self.db_pool.runInteraction(
+                "_reset_federation_positions_txn", self._reset_federation_positions_txn
+            )
+            self._need_to_reset_federation_stream_positions = False
+
+        return await self.db_pool.simple_update_one(
+            table="federation_stream_position",
+            keyvalues={"type": typ, "instance_name": self._instance_name},
+            updatevalues={"stream_id": stream_id},
+            desc="update_federation_out_pos",
+        )
+
+    def _reset_federation_positions_txn(self, txn):
+        """Fiddles with the `federation_stream_position` table to make it match
+        the configured federation sender instances during start up.
+        """
+
+        # The federation sender instances may have changed, so we need to
+        # massage the `federation_stream_position` table to have a row per type
+        # per instance sending federation. If there is a mismatch we update the
+        # table with the correct rows using the *minimum* stream ID seen. This
+        # may result in resending of events/EDUs to remote servers, but that is
+        # preferable to dropping them.
+
+        if not self._send_federation:
+            return
+
+        # Pull out the configured instances. If we don't have a shard config then
+        # we assume that we're the only instance sending.
+        configured_instances = self._federation_shard_config.instances
+        if not configured_instances:
+            configured_instances = [self._instance_name]
+        elif self._instance_name not in configured_instances:
+            return
+
+        instances_in_table = self.db_pool.simple_select_onecol_txn(
+            txn,
+            table="federation_stream_position",
+            keyvalues={},
+            retcol="instance_name",
+        )
+
+        if set(instances_in_table) == set(configured_instances):
+            # Nothing to do
+            return
+
+        sql = """
+            SELECT type, MIN(stream_id) FROM federation_stream_position
+            GROUP BY type
+        """
+        txn.execute(sql)
+        min_positions = dict(txn)  # Map from type -> min position
+
+        # Ensure we do actually have some values here
+        assert set(min_positions) == {"federation", "events"}
+
+        sql = """
+            DELETE FROM federation_stream_position
+            WHERE NOT (%s)
+        """
+        clause, args = make_in_list_sql_clause(
+            txn.database_engine, "instance_name", configured_instances
+        )
+        txn.execute(sql % (clause,), args)
+
+        for typ, stream_id in min_positions.items():
+            self.db_pool.simple_upsert_txn(
+                txn,
+                table="federation_stream_position",
+                keyvalues={"type": typ, "instance_name": self._instance_name},
+                values={"stream_id": stream_id},
+            )
+
+    def has_room_changed_since(self, room_id, stream_id):
+        return self._events_stream_cache.has_entity_changed(room_id, stream_id)
+
+    def _paginate_room_events_txn(
+        self,
+        txn,
+        room_id,
+        from_token,
+        to_token=None,
+        direction="b",
+        limit=-1,
+        event_filter=None,
+    ):
+        """Returns list of events before or after a given token.
+
+        Args:
+            txn
+            room_id (str)
+            from_token (RoomStreamToken): The token used to stream from
+            to_token (RoomStreamToken|None): A token which if given limits the
+                results to only those before
+            direction(char): Either 'b' or 'f' to indicate whether we are
+                paginating forwards or backwards from `from_key`.
+            limit (int): The maximum number of events to return.
+            event_filter (Filter|None): If provided filters the events to
+                those that match the filter.
+
+        Returns:
+            Deferred[tuple[list[_EventDictReturn], str]]: Returns the results
+            as a list of _EventDictReturn and a token that points to the end
+            of the result set. If no events are returned then the end of the
+            stream has been reached (i.e. there are no events between
+            `from_token` and `to_token`), or `limit` is zero.
+        """
+
+        assert int(limit) >= 0
+
+        # Tokens really represent positions between elements, but we use
+        # the convention of pointing to the event before the gap. Hence
+        # we have a bit of asymmetry when it comes to equalities.
+        args = [False, room_id]
+        if direction == "b":
+            order = "DESC"
+        else:
+            order = "ASC"
+
+        bounds = generate_pagination_where_clause(
+            direction=direction,
+            column_names=("topological_ordering", "stream_ordering"),
+            from_token=from_token,
+            to_token=to_token,
+            engine=self.database_engine,
+        )
+
+        filter_clause, filter_args = filter_to_clause(event_filter)
+
+        if filter_clause:
+            bounds += " AND " + filter_clause
+            args.extend(filter_args)
+
+        args.append(int(limit))
+
+        select_keywords = "SELECT"
+        join_clause = ""
+        if event_filter and event_filter.labels:
+            # If we're not filtering on a label, then joining on event_labels will
+            # return as many row for a single event as the number of labels it has. To
+            # avoid this, only join if we're filtering on at least one label.
+            join_clause = """
+                LEFT JOIN event_labels
+                USING (event_id, room_id, topological_ordering)
+            """
+            if len(event_filter.labels) > 1:
+                # Using DISTINCT in this SELECT query is quite expensive, because it
+                # requires the engine to sort on the entire (not limited) result set,
+                # i.e. the entire events table. We only need to use it when we're
+                # filtering on more than two labels, because that's the only scenario
+                # in which we can possibly to get multiple times the same event ID in
+                # the results.
+                select_keywords += "DISTINCT"
+
+        sql = """
+            %(select_keywords)s event_id, topological_ordering, stream_ordering
+            FROM events
+            %(join_clause)s
+            WHERE outlier = ? AND room_id = ? AND %(bounds)s
+            ORDER BY topological_ordering %(order)s,
+            stream_ordering %(order)s LIMIT ?
+        """ % {
+            "select_keywords": select_keywords,
+            "join_clause": join_clause,
+            "bounds": bounds,
+            "order": order,
+        }
+
+        txn.execute(sql, args)
+
+        rows = [_EventDictReturn(row[0], row[1], row[2]) for row in txn]
+
+        if rows:
+            topo = rows[-1].topological_ordering
+            toke = rows[-1].stream_ordering
+            if direction == "b":
+                # Tokens are positions between events.
+                # This token points *after* the last event in the chunk.
+                # We need it to point to the event before it in the chunk
+                # when we are going backwards so we subtract one from the
+                # stream part.
+                toke -= 1
+            next_token = RoomStreamToken(topo, toke)
+        else:
+            # TODO (erikj): We should work out what to do here instead.
+            next_token = to_token if to_token else from_token
+
+        return rows, str(next_token)
+
+    @defer.inlineCallbacks
+    def paginate_room_events(
+        self, room_id, from_key, to_key=None, direction="b", limit=-1, event_filter=None
+    ):
+        """Returns list of events before or after a given token.
+
+        Args:
+            room_id (str)
+            from_key (str): The token used to stream from
+            to_key (str|None): A token which if given limits the results to
+                only those before
+            direction(char): Either 'b' or 'f' to indicate whether we are
+                paginating forwards or backwards from `from_key`.
+            limit (int): The maximum number of events to return.
+            event_filter (Filter|None): If provided filters the events to
+                those that match the filter.
+
+        Returns:
+            tuple[list[FrozenEvent], str]: Returns the results as a list of
+            events and a token that points to the end of the result set. If no
+            events are returned then the end of the stream has been reached
+            (i.e. there are no events between `from_key` and `to_key`).
+        """
+
+        from_key = RoomStreamToken.parse(from_key)
+        if to_key:
+            to_key = RoomStreamToken.parse(to_key)
+
+        rows, token = yield self.db_pool.runInteraction(
+            "paginate_room_events",
+            self._paginate_room_events_txn,
+            room_id,
+            from_key,
+            to_key,
+            direction,
+            limit,
+            event_filter,
+        )
+
+        events = yield self.get_events_as_list(
+            [r.event_id for r in rows], get_prev_content=True
+        )
+
+        self._set_before_and_after(events, rows)
+
+        return (events, token)
+
+
+class StreamStore(StreamWorkerStore):
+    def get_room_max_stream_ordering(self):
+        return self._stream_id_gen.get_current_token()
+
+    def get_room_min_stream_ordering(self):
+        return self._backfill_id_gen.get_current_token()
diff --git a/synapse/storage/databases/main/tags.py b/synapse/storage/databases/main/tags.py
new file mode 100644
index 0000000000..eedd2d96c3
--- /dev/null
+++ b/synapse/storage/databases/main/tags.py
@@ -0,0 +1,288 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from typing import List, Tuple
+
+from canonicaljson import json
+
+from twisted.internet import defer
+
+from synapse.storage._base import db_to_json
+from synapse.storage.databases.main.account_data import AccountDataWorkerStore
+from synapse.util.caches.descriptors import cached
+
+logger = logging.getLogger(__name__)
+
+
+class TagsWorkerStore(AccountDataWorkerStore):
+    @cached()
+    def get_tags_for_user(self, user_id):
+        """Get all the tags for a user.
+
+
+        Args:
+            user_id(str): The user to get the tags for.
+        Returns:
+            A deferred dict mapping from room_id strings to dicts mapping from
+            tag strings to tag content.
+        """
+
+        deferred = self.db_pool.simple_select_list(
+            "room_tags", {"user_id": user_id}, ["room_id", "tag", "content"]
+        )
+
+        @deferred.addCallback
+        def tags_by_room(rows):
+            tags_by_room = {}
+            for row in rows:
+                room_tags = tags_by_room.setdefault(row["room_id"], {})
+                room_tags[row["tag"]] = db_to_json(row["content"])
+            return tags_by_room
+
+        return deferred
+
+    async def get_all_updated_tags(
+        self, instance_name: str, last_id: int, current_id: int, limit: int
+    ) -> Tuple[List[Tuple[int, tuple]], int, bool]:
+        """Get updates for tags replication stream.
+
+        Args:
+            instance_name: The writer we want to fetch updates from. Unused
+                here since there is only ever one writer.
+            last_id: The token to fetch updates from. Exclusive.
+            current_id: The token to fetch updates up to. Inclusive.
+            limit: The requested limit for the number of rows to return. The
+                function may return more or fewer rows.
+
+        Returns:
+            A tuple consisting of: the updates, a token to use to fetch
+            subsequent updates, and whether we returned fewer rows than exists
+            between the requested tokens due to the limit.
+
+            The token returned can be used in a subsequent call to this
+            function to get further updatees.
+
+            The updates are a list of 2-tuples of stream ID and the row data
+        """
+
+        if last_id == current_id:
+            return [], current_id, False
+
+        def get_all_updated_tags_txn(txn):
+            sql = (
+                "SELECT stream_id, user_id, room_id"
+                " FROM room_tags_revisions as r"
+                " WHERE ? < stream_id AND stream_id <= ?"
+                " ORDER BY stream_id ASC LIMIT ?"
+            )
+            txn.execute(sql, (last_id, current_id, limit))
+            return txn.fetchall()
+
+        tag_ids = await self.db_pool.runInteraction(
+            "get_all_updated_tags", get_all_updated_tags_txn
+        )
+
+        def get_tag_content(txn, tag_ids):
+            sql = "SELECT tag, content FROM room_tags WHERE user_id=? AND room_id=?"
+            results = []
+            for stream_id, user_id, room_id in tag_ids:
+                txn.execute(sql, (user_id, room_id))
+                tags = []
+                for tag, content in txn:
+                    tags.append(json.dumps(tag) + ":" + content)
+                tag_json = "{" + ",".join(tags) + "}"
+                results.append((stream_id, (user_id, room_id, tag_json)))
+
+            return results
+
+        batch_size = 50
+        results = []
+        for i in range(0, len(tag_ids), batch_size):
+            tags = await self.db_pool.runInteraction(
+                "get_all_updated_tag_content",
+                get_tag_content,
+                tag_ids[i : i + batch_size],
+            )
+            results.extend(tags)
+
+        limited = False
+        upto_token = current_id
+        if len(results) >= limit:
+            upto_token = results[-1][0]
+            limited = True
+
+        return results, upto_token, limited
+
+    @defer.inlineCallbacks
+    def get_updated_tags(self, user_id, stream_id):
+        """Get all the tags for the rooms where the tags have changed since the
+        given version
+
+        Args:
+            user_id(str): The user to get the tags for.
+            stream_id(int): The earliest update to get for the user.
+        Returns:
+            A deferred dict mapping from room_id strings to lists of tag
+            strings for all the rooms that changed since the stream_id token.
+        """
+
+        def get_updated_tags_txn(txn):
+            sql = (
+                "SELECT room_id from room_tags_revisions"
+                " WHERE user_id = ? AND stream_id > ?"
+            )
+            txn.execute(sql, (user_id, stream_id))
+            room_ids = [row[0] for row in txn]
+            return room_ids
+
+        changed = self._account_data_stream_cache.has_entity_changed(
+            user_id, int(stream_id)
+        )
+        if not changed:
+            return {}
+
+        room_ids = yield self.db_pool.runInteraction(
+            "get_updated_tags", get_updated_tags_txn
+        )
+
+        results = {}
+        if room_ids:
+            tags_by_room = yield self.get_tags_for_user(user_id)
+            for room_id in room_ids:
+                results[room_id] = tags_by_room.get(room_id, {})
+
+        return results
+
+    def get_tags_for_room(self, user_id, room_id):
+        """Get all the tags for the given room
+        Args:
+            user_id(str): The user to get tags for
+            room_id(str): The room to get tags for
+        Returns:
+            A deferred list of string tags.
+        """
+        return self.db_pool.simple_select_list(
+            table="room_tags",
+            keyvalues={"user_id": user_id, "room_id": room_id},
+            retcols=("tag", "content"),
+            desc="get_tags_for_room",
+        ).addCallback(
+            lambda rows: {row["tag"]: db_to_json(row["content"]) for row in rows}
+        )
+
+
+class TagsStore(TagsWorkerStore):
+    @defer.inlineCallbacks
+    def add_tag_to_room(self, user_id, room_id, tag, content):
+        """Add a tag to a room for a user.
+        Args:
+            user_id(str): The user to add a tag for.
+            room_id(str): The room to add a tag for.
+            tag(str): The tag name to add.
+            content(dict): A json object to associate with the tag.
+        Returns:
+            A deferred that completes once the tag has been added.
+        """
+        content_json = json.dumps(content)
+
+        def add_tag_txn(txn, next_id):
+            self.db_pool.simple_upsert_txn(
+                txn,
+                table="room_tags",
+                keyvalues={"user_id": user_id, "room_id": room_id, "tag": tag},
+                values={"content": content_json},
+            )
+            self._update_revision_txn(txn, user_id, room_id, next_id)
+
+        with self._account_data_id_gen.get_next() as next_id:
+            yield self.db_pool.runInteraction("add_tag", add_tag_txn, next_id)
+
+        self.get_tags_for_user.invalidate((user_id,))
+
+        result = self._account_data_id_gen.get_current_token()
+        return result
+
+    @defer.inlineCallbacks
+    def remove_tag_from_room(self, user_id, room_id, tag):
+        """Remove a tag from a room for a user.
+        Returns:
+            A deferred that completes once the tag has been removed
+        """
+
+        def remove_tag_txn(txn, next_id):
+            sql = (
+                "DELETE FROM room_tags "
+                " WHERE user_id = ? AND room_id = ? AND tag = ?"
+            )
+            txn.execute(sql, (user_id, room_id, tag))
+            self._update_revision_txn(txn, user_id, room_id, next_id)
+
+        with self._account_data_id_gen.get_next() as next_id:
+            yield self.db_pool.runInteraction("remove_tag", remove_tag_txn, next_id)
+
+        self.get_tags_for_user.invalidate((user_id,))
+
+        result = self._account_data_id_gen.get_current_token()
+        return result
+
+    def _update_revision_txn(self, txn, user_id, room_id, next_id):
+        """Update the latest revision of the tags for the given user and room.
+
+        Args:
+            txn: The database cursor
+            user_id(str): The ID of the user.
+            room_id(str): The ID of the room.
+            next_id(int): The the revision to advance to.
+        """
+
+        txn.call_after(
+            self._account_data_stream_cache.entity_has_changed, user_id, next_id
+        )
+
+        # Note: This is only here for backwards compat to allow admins to
+        # roll back to a previous Synapse version. Next time we update the
+        # database version we can remove this table.
+        update_max_id_sql = (
+            "UPDATE account_data_max_stream_id"
+            " SET stream_id = ?"
+            " WHERE stream_id < ?"
+        )
+        txn.execute(update_max_id_sql, (next_id, next_id))
+
+        update_sql = (
+            "UPDATE room_tags_revisions"
+            " SET stream_id = ?"
+            " WHERE user_id = ?"
+            " AND room_id = ?"
+        )
+        txn.execute(update_sql, (next_id, user_id, room_id))
+
+        if txn.rowcount == 0:
+            insert_sql = (
+                "INSERT INTO room_tags_revisions (user_id, room_id, stream_id)"
+                " VALUES (?, ?, ?)"
+            )
+            try:
+                txn.execute(insert_sql, (user_id, room_id, next_id))
+            except self.database_engine.module.IntegrityError:
+                # Ignore insertion errors. It doesn't matter if the row wasn't
+                # inserted because if two updates happend concurrently the one
+                # with the higher stream_id will not be reported to a client
+                # unless the previous update has completed. It doesn't matter
+                # which stream_id ends up in the table, as long as it is higher
+                # than the id that the client has.
+                pass
diff --git a/synapse/storage/databases/main/transactions.py b/synapse/storage/databases/main/transactions.py
new file mode 100644
index 0000000000..8804c0e4ac
--- /dev/null
+++ b/synapse/storage/databases/main/transactions.py
@@ -0,0 +1,269 @@
+# -*- coding: utf-8 -*-
+# Copyright 2014-2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+from collections import namedtuple
+
+from canonicaljson import encode_canonical_json
+
+from twisted.internet import defer
+
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.storage.database import DatabasePool
+from synapse.util.caches.expiringcache import ExpiringCache
+
+db_binary_type = memoryview
+
+logger = logging.getLogger(__name__)
+
+
+_TransactionRow = namedtuple(
+    "_TransactionRow",
+    ("id", "transaction_id", "destination", "ts", "response_code", "response_json"),
+)
+
+_UpdateTransactionRow = namedtuple(
+    "_TransactionRow", ("response_code", "response_json")
+)
+
+SENTINEL = object()
+
+
+class TransactionStore(SQLBaseStore):
+    """A collection of queries for handling PDUs.
+    """
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(TransactionStore, self).__init__(database, db_conn, hs)
+
+        self._clock.looping_call(self._start_cleanup_transactions, 30 * 60 * 1000)
+
+        self._destination_retry_cache = ExpiringCache(
+            cache_name="get_destination_retry_timings",
+            clock=self._clock,
+            expiry_ms=5 * 60 * 1000,
+        )
+
+    def get_received_txn_response(self, transaction_id, origin):
+        """For an incoming transaction from a given origin, check if we have
+        already responded to it. If so, return the response code and response
+        body (as a dict).
+
+        Args:
+            transaction_id (str)
+            origin(str)
+
+        Returns:
+            tuple: None if we have not previously responded to
+            this transaction or a 2-tuple of (int, dict)
+        """
+
+        return self.db_pool.runInteraction(
+            "get_received_txn_response",
+            self._get_received_txn_response,
+            transaction_id,
+            origin,
+        )
+
+    def _get_received_txn_response(self, txn, transaction_id, origin):
+        result = self.db_pool.simple_select_one_txn(
+            txn,
+            table="received_transactions",
+            keyvalues={"transaction_id": transaction_id, "origin": origin},
+            retcols=(
+                "transaction_id",
+                "origin",
+                "ts",
+                "response_code",
+                "response_json",
+                "has_been_referenced",
+            ),
+            allow_none=True,
+        )
+
+        if result and result["response_code"]:
+            return result["response_code"], db_to_json(result["response_json"])
+
+        else:
+            return None
+
+    def set_received_txn_response(self, transaction_id, origin, code, response_dict):
+        """Persist the response we returened for an incoming transaction, and
+        should return for subsequent transactions with the same transaction_id
+        and origin.
+
+        Args:
+            txn
+            transaction_id (str)
+            origin (str)
+            code (int)
+            response_json (str)
+        """
+
+        return self.db_pool.simple_insert(
+            table="received_transactions",
+            values={
+                "transaction_id": transaction_id,
+                "origin": origin,
+                "response_code": code,
+                "response_json": db_binary_type(encode_canonical_json(response_dict)),
+                "ts": self._clock.time_msec(),
+            },
+            or_ignore=True,
+            desc="set_received_txn_response",
+        )
+
+    @defer.inlineCallbacks
+    def get_destination_retry_timings(self, destination):
+        """Gets the current retry timings (if any) for a given destination.
+
+        Args:
+            destination (str)
+
+        Returns:
+            None if not retrying
+            Otherwise a dict for the retry scheme
+        """
+
+        result = self._destination_retry_cache.get(destination, SENTINEL)
+        if result is not SENTINEL:
+            return result
+
+        result = yield self.db_pool.runInteraction(
+            "get_destination_retry_timings",
+            self._get_destination_retry_timings,
+            destination,
+        )
+
+        # We don't hugely care about race conditions between getting and
+        # invalidating the cache, since we time out fairly quickly anyway.
+        self._destination_retry_cache[destination] = result
+        return result
+
+    def _get_destination_retry_timings(self, txn, destination):
+        result = self.db_pool.simple_select_one_txn(
+            txn,
+            table="destinations",
+            keyvalues={"destination": destination},
+            retcols=("destination", "failure_ts", "retry_last_ts", "retry_interval"),
+            allow_none=True,
+        )
+
+        if result and result["retry_last_ts"] > 0:
+            return result
+        else:
+            return None
+
+    def set_destination_retry_timings(
+        self, destination, failure_ts, retry_last_ts, retry_interval
+    ):
+        """Sets the current retry timings for a given destination.
+        Both timings should be zero if retrying is no longer occuring.
+
+        Args:
+            destination (str)
+            failure_ts (int|None) - when the server started failing (ms since epoch)
+            retry_last_ts (int) - time of last retry attempt in unix epoch ms
+            retry_interval (int) - how long until next retry in ms
+        """
+
+        self._destination_retry_cache.pop(destination, None)
+        return self.db_pool.runInteraction(
+            "set_destination_retry_timings",
+            self._set_destination_retry_timings,
+            destination,
+            failure_ts,
+            retry_last_ts,
+            retry_interval,
+        )
+
+    def _set_destination_retry_timings(
+        self, txn, destination, failure_ts, retry_last_ts, retry_interval
+    ):
+
+        if self.database_engine.can_native_upsert:
+            # Upsert retry time interval if retry_interval is zero (i.e. we're
+            # resetting it) or greater than the existing retry interval.
+
+            sql = """
+                INSERT INTO destinations (
+                    destination, failure_ts, retry_last_ts, retry_interval
+                )
+                    VALUES (?, ?, ?, ?)
+                ON CONFLICT (destination) DO UPDATE SET
+                        failure_ts = EXCLUDED.failure_ts,
+                        retry_last_ts = EXCLUDED.retry_last_ts,
+                        retry_interval = EXCLUDED.retry_interval
+                    WHERE
+                        EXCLUDED.retry_interval = 0
+                        OR destinations.retry_interval < EXCLUDED.retry_interval
+            """
+
+            txn.execute(sql, (destination, failure_ts, retry_last_ts, retry_interval))
+
+            return
+
+        self.database_engine.lock_table(txn, "destinations")
+
+        # We need to be careful here as the data may have changed from under us
+        # due to a worker setting the timings.
+
+        prev_row = self.db_pool.simple_select_one_txn(
+            txn,
+            table="destinations",
+            keyvalues={"destination": destination},
+            retcols=("failure_ts", "retry_last_ts", "retry_interval"),
+            allow_none=True,
+        )
+
+        if not prev_row:
+            self.db_pool.simple_insert_txn(
+                txn,
+                table="destinations",
+                values={
+                    "destination": destination,
+                    "failure_ts": failure_ts,
+                    "retry_last_ts": retry_last_ts,
+                    "retry_interval": retry_interval,
+                },
+            )
+        elif retry_interval == 0 or prev_row["retry_interval"] < retry_interval:
+            self.db_pool.simple_update_one_txn(
+                txn,
+                "destinations",
+                keyvalues={"destination": destination},
+                updatevalues={
+                    "failure_ts": failure_ts,
+                    "retry_last_ts": retry_last_ts,
+                    "retry_interval": retry_interval,
+                },
+            )
+
+    def _start_cleanup_transactions(self):
+        return run_as_background_process(
+            "cleanup_transactions", self._cleanup_transactions
+        )
+
+    def _cleanup_transactions(self):
+        now = self._clock.time_msec()
+        month_ago = now - 30 * 24 * 60 * 60 * 1000
+
+        def _cleanup_transactions_txn(txn):
+            txn.execute("DELETE FROM received_transactions WHERE ts < ?", (month_ago,))
+
+        return self.db_pool.runInteraction(
+            "_cleanup_transactions", _cleanup_transactions_txn
+        )
diff --git a/synapse/storage/databases/main/ui_auth.py b/synapse/storage/databases/main/ui_auth.py
new file mode 100644
index 0000000000..37276f73f8
--- /dev/null
+++ b/synapse/storage/databases/main/ui_auth.py
@@ -0,0 +1,300 @@
+# -*- coding: utf-8 -*-
+# Copyright 2020 Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from typing import Any, Dict, Optional, Union
+
+import attr
+from canonicaljson import json
+
+from synapse.api.errors import StoreError
+from synapse.storage._base import SQLBaseStore, db_to_json
+from synapse.types import JsonDict
+from synapse.util import stringutils as stringutils
+
+
+@attr.s
+class UIAuthSessionData:
+    session_id = attr.ib(type=str)
+    # The dictionary from the client root level, not the 'auth' key.
+    clientdict = attr.ib(type=JsonDict)
+    # The URI and method the session was intiatied with. These are checked at
+    # each stage of the authentication to ensure that the asked for operation
+    # has not changed.
+    uri = attr.ib(type=str)
+    method = attr.ib(type=str)
+    # A string description of the operation that the current authentication is
+    # authorising.
+    description = attr.ib(type=str)
+
+
+class UIAuthWorkerStore(SQLBaseStore):
+    """
+    Manage user interactive authentication sessions.
+    """
+
+    async def create_ui_auth_session(
+        self, clientdict: JsonDict, uri: str, method: str, description: str,
+    ) -> UIAuthSessionData:
+        """
+        Creates a new user interactive authentication session.
+
+        The session can be used to track the stages necessary to authenticate a
+        user across multiple HTTP requests.
+
+        Args:
+            clientdict:
+                The dictionary from the client root level, not the 'auth' key.
+            uri:
+                The URI this session was initiated with, this is checked at each
+                stage of the authentication to ensure that the asked for
+                operation has not changed.
+            method:
+                The method this session was initiated with, this is checked at each
+                stage of the authentication to ensure that the asked for
+                operation has not changed.
+            description:
+                A string description of the operation that the current
+                authentication is authorising.
+        Returns:
+            The newly created session.
+        Raises:
+            StoreError if a unique session ID cannot be generated.
+        """
+        # The clientdict gets stored as JSON.
+        clientdict_json = json.dumps(clientdict)
+
+        # autogen a session ID and try to create it. We may clash, so just
+        # try a few times till one goes through, giving up eventually.
+        attempts = 0
+        while attempts < 5:
+            session_id = stringutils.random_string(24)
+
+            try:
+                await self.db_pool.simple_insert(
+                    table="ui_auth_sessions",
+                    values={
+                        "session_id": session_id,
+                        "clientdict": clientdict_json,
+                        "uri": uri,
+                        "method": method,
+                        "description": description,
+                        "serverdict": "{}",
+                        "creation_time": self.hs.get_clock().time_msec(),
+                    },
+                    desc="create_ui_auth_session",
+                )
+                return UIAuthSessionData(
+                    session_id, clientdict, uri, method, description
+                )
+            except self.db_pool.engine.module.IntegrityError:
+                attempts += 1
+        raise StoreError(500, "Couldn't generate a session ID.")
+
+    async def get_ui_auth_session(self, session_id: str) -> UIAuthSessionData:
+        """Retrieve a UI auth session.
+
+        Args:
+            session_id: The ID of the session.
+        Returns:
+            A dict containing the device information.
+        Raises:
+            StoreError if the session is not found.
+        """
+        result = await self.db_pool.simple_select_one(
+            table="ui_auth_sessions",
+            keyvalues={"session_id": session_id},
+            retcols=("clientdict", "uri", "method", "description"),
+            desc="get_ui_auth_session",
+        )
+
+        result["clientdict"] = db_to_json(result["clientdict"])
+
+        return UIAuthSessionData(session_id, **result)
+
+    async def mark_ui_auth_stage_complete(
+        self, session_id: str, stage_type: str, result: Union[str, bool, JsonDict],
+    ):
+        """
+        Mark a session stage as completed.
+
+        Args:
+            session_id: The ID of the corresponding session.
+            stage_type: The completed stage type.
+            result: The result of the stage verification.
+        Raises:
+            StoreError if the session cannot be found.
+        """
+        # Add (or update) the results of the current stage to the database.
+        #
+        # Note that we need to allow for the same stage to complete multiple
+        # times here so that registration is idempotent.
+        try:
+            await self.db_pool.simple_upsert(
+                table="ui_auth_sessions_credentials",
+                keyvalues={"session_id": session_id, "stage_type": stage_type},
+                values={"result": json.dumps(result)},
+                desc="mark_ui_auth_stage_complete",
+            )
+        except self.db_pool.engine.module.IntegrityError:
+            raise StoreError(400, "Unknown session ID: %s" % (session_id,))
+
+    async def get_completed_ui_auth_stages(
+        self, session_id: str
+    ) -> Dict[str, Union[str, bool, JsonDict]]:
+        """
+        Retrieve the completed stages of a UI authentication session.
+
+        Args:
+            session_id: The ID of the session.
+        Returns:
+            The completed stages mapped to the result of the verification of
+            that auth-type.
+        """
+        results = {}
+        for row in await self.db_pool.simple_select_list(
+            table="ui_auth_sessions_credentials",
+            keyvalues={"session_id": session_id},
+            retcols=("stage_type", "result"),
+            desc="get_completed_ui_auth_stages",
+        ):
+            results[row["stage_type"]] = db_to_json(row["result"])
+
+        return results
+
+    async def set_ui_auth_clientdict(
+        self, session_id: str, clientdict: JsonDict
+    ) -> None:
+        """
+        Store an updated clientdict for a given session ID.
+
+        Args:
+            session_id: The ID of this session as returned from check_auth
+            clientdict:
+                The dictionary from the client root level, not the 'auth' key.
+        """
+        # The clientdict gets stored as JSON.
+        clientdict_json = json.dumps(clientdict)
+
+        await self.db_pool.simple_update_one(
+            table="ui_auth_sessions",
+            keyvalues={"session_id": session_id},
+            updatevalues={"clientdict": clientdict_json},
+            desc="set_ui_auth_client_dict",
+        )
+
+    async def set_ui_auth_session_data(self, session_id: str, key: str, value: Any):
+        """
+        Store a key-value pair into the sessions data associated with this
+        request. This data is stored server-side and cannot be modified by
+        the client.
+
+        Args:
+            session_id: The ID of this session as returned from check_auth
+            key: The key to store the data under
+            value: The data to store
+        Raises:
+            StoreError if the session cannot be found.
+        """
+        await self.db_pool.runInteraction(
+            "set_ui_auth_session_data",
+            self._set_ui_auth_session_data_txn,
+            session_id,
+            key,
+            value,
+        )
+
+    def _set_ui_auth_session_data_txn(self, txn, session_id: str, key: str, value: Any):
+        # Get the current value.
+        result = self.db_pool.simple_select_one_txn(
+            txn,
+            table="ui_auth_sessions",
+            keyvalues={"session_id": session_id},
+            retcols=("serverdict",),
+        )
+
+        # Update it and add it back to the database.
+        serverdict = db_to_json(result["serverdict"])
+        serverdict[key] = value
+
+        self.db_pool.simple_update_one_txn(
+            txn,
+            table="ui_auth_sessions",
+            keyvalues={"session_id": session_id},
+            updatevalues={"serverdict": json.dumps(serverdict)},
+        )
+
+    async def get_ui_auth_session_data(
+        self, session_id: str, key: str, default: Optional[Any] = None
+    ) -> Any:
+        """
+        Retrieve data stored with set_session_data
+
+        Args:
+            session_id: The ID of this session as returned from check_auth
+            key: The key to store the data under
+            default: Value to return if the key has not been set
+        Raises:
+            StoreError if the session cannot be found.
+        """
+        result = await self.db_pool.simple_select_one(
+            table="ui_auth_sessions",
+            keyvalues={"session_id": session_id},
+            retcols=("serverdict",),
+            desc="get_ui_auth_session_data",
+        )
+
+        serverdict = db_to_json(result["serverdict"])
+
+        return serverdict.get(key, default)
+
+
+class UIAuthStore(UIAuthWorkerStore):
+    def delete_old_ui_auth_sessions(self, expiration_time: int):
+        """
+        Remove sessions which were last used earlier than the expiration time.
+
+        Args:
+            expiration_time: The latest time that is still considered valid.
+                This is an epoch time in milliseconds.
+
+        """
+        return self.db_pool.runInteraction(
+            "delete_old_ui_auth_sessions",
+            self._delete_old_ui_auth_sessions_txn,
+            expiration_time,
+        )
+
+    def _delete_old_ui_auth_sessions_txn(self, txn, expiration_time: int):
+        # Get the expired sessions.
+        sql = "SELECT session_id FROM ui_auth_sessions WHERE creation_time <= ?"
+        txn.execute(sql, [expiration_time])
+        session_ids = [r[0] for r in txn.fetchall()]
+
+        # Delete the corresponding completed credentials.
+        self.db_pool.simple_delete_many_txn(
+            txn,
+            table="ui_auth_sessions_credentials",
+            column="session_id",
+            iterable=session_ids,
+            keyvalues={},
+        )
+
+        # Finally, delete the sessions.
+        self.db_pool.simple_delete_many_txn(
+            txn,
+            table="ui_auth_sessions",
+            column="session_id",
+            iterable=session_ids,
+            keyvalues={},
+        )
diff --git a/synapse/storage/databases/main/user_directory.py b/synapse/storage/databases/main/user_directory.py
new file mode 100644
index 0000000000..d73a8e8ab9
--- /dev/null
+++ b/synapse/storage/databases/main/user_directory.py
@@ -0,0 +1,847 @@
+# -*- coding: utf-8 -*-
+# Copyright 2017 Vector Creations Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import logging
+import re
+
+from twisted.internet import defer
+
+from synapse.api.constants import EventTypes, JoinRules
+from synapse.storage.database import DatabasePool
+from synapse.storage.databases.main.state import StateFilter
+from synapse.storage.databases.main.state_deltas import StateDeltasStore
+from synapse.storage.engines import PostgresEngine, Sqlite3Engine
+from synapse.types import get_domain_from_id, get_localpart_from_id
+from synapse.util.caches.descriptors import cached
+
+logger = logging.getLogger(__name__)
+
+
+TEMP_TABLE = "_temp_populate_user_directory"
+
+
+class UserDirectoryBackgroundUpdateStore(StateDeltasStore):
+
+    # How many records do we calculate before sending it to
+    # add_users_who_share_private_rooms?
+    SHARE_PRIVATE_WORKING_SET = 500
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(UserDirectoryBackgroundUpdateStore, self).__init__(database, db_conn, hs)
+
+        self.server_name = hs.hostname
+
+        self.db_pool.updates.register_background_update_handler(
+            "populate_user_directory_createtables",
+            self._populate_user_directory_createtables,
+        )
+        self.db_pool.updates.register_background_update_handler(
+            "populate_user_directory_process_rooms",
+            self._populate_user_directory_process_rooms,
+        )
+        self.db_pool.updates.register_background_update_handler(
+            "populate_user_directory_process_users",
+            self._populate_user_directory_process_users,
+        )
+        self.db_pool.updates.register_background_update_handler(
+            "populate_user_directory_cleanup", self._populate_user_directory_cleanup
+        )
+
+    @defer.inlineCallbacks
+    def _populate_user_directory_createtables(self, progress, batch_size):
+
+        # Get all the rooms that we want to process.
+        def _make_staging_area(txn):
+            sql = (
+                "CREATE TABLE IF NOT EXISTS "
+                + TEMP_TABLE
+                + "_rooms(room_id TEXT NOT NULL, events BIGINT NOT NULL)"
+            )
+            txn.execute(sql)
+
+            sql = (
+                "CREATE TABLE IF NOT EXISTS "
+                + TEMP_TABLE
+                + "_position(position TEXT NOT NULL)"
+            )
+            txn.execute(sql)
+
+            # Get rooms we want to process from the database
+            sql = """
+                SELECT room_id, count(*) FROM current_state_events
+                GROUP BY room_id
+            """
+            txn.execute(sql)
+            rooms = [{"room_id": x[0], "events": x[1]} for x in txn.fetchall()]
+            self.db_pool.simple_insert_many_txn(txn, TEMP_TABLE + "_rooms", rooms)
+            del rooms
+
+            # If search all users is on, get all the users we want to add.
+            if self.hs.config.user_directory_search_all_users:
+                sql = (
+                    "CREATE TABLE IF NOT EXISTS "
+                    + TEMP_TABLE
+                    + "_users(user_id TEXT NOT NULL)"
+                )
+                txn.execute(sql)
+
+                txn.execute("SELECT name FROM users")
+                users = [{"user_id": x[0]} for x in txn.fetchall()]
+
+                self.db_pool.simple_insert_many_txn(txn, TEMP_TABLE + "_users", users)
+
+        new_pos = yield self.get_max_stream_id_in_current_state_deltas()
+        yield self.db_pool.runInteraction(
+            "populate_user_directory_temp_build", _make_staging_area
+        )
+        yield self.db_pool.simple_insert(
+            TEMP_TABLE + "_position", {"position": new_pos}
+        )
+
+        yield self.db_pool.updates._end_background_update(
+            "populate_user_directory_createtables"
+        )
+        return 1
+
+    @defer.inlineCallbacks
+    def _populate_user_directory_cleanup(self, progress, batch_size):
+        """
+        Update the user directory stream position, then clean up the old tables.
+        """
+        position = yield self.db_pool.simple_select_one_onecol(
+            TEMP_TABLE + "_position", None, "position"
+        )
+        yield self.update_user_directory_stream_pos(position)
+
+        def _delete_staging_area(txn):
+            txn.execute("DROP TABLE IF EXISTS " + TEMP_TABLE + "_rooms")
+            txn.execute("DROP TABLE IF EXISTS " + TEMP_TABLE + "_users")
+            txn.execute("DROP TABLE IF EXISTS " + TEMP_TABLE + "_position")
+
+        yield self.db_pool.runInteraction(
+            "populate_user_directory_cleanup", _delete_staging_area
+        )
+
+        yield self.db_pool.updates._end_background_update(
+            "populate_user_directory_cleanup"
+        )
+        return 1
+
+    @defer.inlineCallbacks
+    def _populate_user_directory_process_rooms(self, progress, batch_size):
+        """
+        Args:
+            progress (dict)
+            batch_size (int): Maximum number of state events to process
+                per cycle.
+        """
+        state = self.hs.get_state_handler()
+
+        # If we don't have progress filed, delete everything.
+        if not progress:
+            yield self.delete_all_from_user_dir()
+
+        def _get_next_batch(txn):
+            # Only fetch 250 rooms, so we don't fetch too many at once, even
+            # if those 250 rooms have less than batch_size state events.
+            sql = """
+                SELECT room_id, events FROM %s
+                ORDER BY events DESC
+                LIMIT 250
+            """ % (
+                TEMP_TABLE + "_rooms",
+            )
+            txn.execute(sql)
+            rooms_to_work_on = txn.fetchall()
+
+            if not rooms_to_work_on:
+                return None
+
+            # Get how many are left to process, so we can give status on how
+            # far we are in processing
+            txn.execute("SELECT COUNT(*) FROM " + TEMP_TABLE + "_rooms")
+            progress["remaining"] = txn.fetchone()[0]
+
+            return rooms_to_work_on
+
+        rooms_to_work_on = yield self.db_pool.runInteraction(
+            "populate_user_directory_temp_read", _get_next_batch
+        )
+
+        # No more rooms -- complete the transaction.
+        if not rooms_to_work_on:
+            yield self.db_pool.updates._end_background_update(
+                "populate_user_directory_process_rooms"
+            )
+            return 1
+
+        logger.debug(
+            "Processing the next %d rooms of %d remaining"
+            % (len(rooms_to_work_on), progress["remaining"])
+        )
+
+        processed_event_count = 0
+
+        for room_id, event_count in rooms_to_work_on:
+            is_in_room = yield self.is_host_joined(room_id, self.server_name)
+
+            if is_in_room:
+                is_public = yield self.is_room_world_readable_or_publicly_joinable(
+                    room_id
+                )
+
+                users_with_profile = yield defer.ensureDeferred(
+                    state.get_current_users_in_room(room_id)
+                )
+                user_ids = set(users_with_profile)
+
+                # Update each user in the user directory.
+                for user_id, profile in users_with_profile.items():
+                    yield self.update_profile_in_user_dir(
+                        user_id, profile.display_name, profile.avatar_url
+                    )
+
+                to_insert = set()
+
+                if is_public:
+                    for user_id in user_ids:
+                        if self.get_if_app_services_interested_in_user(user_id):
+                            continue
+
+                        to_insert.add(user_id)
+
+                    if to_insert:
+                        yield self.add_users_in_public_rooms(room_id, to_insert)
+                        to_insert.clear()
+                else:
+                    for user_id in user_ids:
+                        if not self.hs.is_mine_id(user_id):
+                            continue
+
+                        if self.get_if_app_services_interested_in_user(user_id):
+                            continue
+
+                        for other_user_id in user_ids:
+                            if user_id == other_user_id:
+                                continue
+
+                            user_set = (user_id, other_user_id)
+                            to_insert.add(user_set)
+
+                            # If it gets too big, stop and write to the database
+                            # to prevent storing too much in RAM.
+                            if len(to_insert) >= self.SHARE_PRIVATE_WORKING_SET:
+                                yield self.add_users_who_share_private_room(
+                                    room_id, to_insert
+                                )
+                                to_insert.clear()
+
+                    if to_insert:
+                        yield self.add_users_who_share_private_room(room_id, to_insert)
+                        to_insert.clear()
+
+            # We've finished a room. Delete it from the table.
+            yield self.db_pool.simple_delete_one(
+                TEMP_TABLE + "_rooms", {"room_id": room_id}
+            )
+            # Update the remaining counter.
+            progress["remaining"] -= 1
+            yield self.db_pool.runInteraction(
+                "populate_user_directory",
+                self.db_pool.updates._background_update_progress_txn,
+                "populate_user_directory_process_rooms",
+                progress,
+            )
+
+            processed_event_count += event_count
+
+            if processed_event_count > batch_size:
+                # Don't process any more rooms, we've hit our batch size.
+                return processed_event_count
+
+        return processed_event_count
+
+    @defer.inlineCallbacks
+    def _populate_user_directory_process_users(self, progress, batch_size):
+        """
+        If search_all_users is enabled, add all of the users to the user directory.
+        """
+        if not self.hs.config.user_directory_search_all_users:
+            yield self.db_pool.updates._end_background_update(
+                "populate_user_directory_process_users"
+            )
+            return 1
+
+        def _get_next_batch(txn):
+            sql = "SELECT user_id FROM %s LIMIT %s" % (
+                TEMP_TABLE + "_users",
+                str(batch_size),
+            )
+            txn.execute(sql)
+            users_to_work_on = txn.fetchall()
+
+            if not users_to_work_on:
+                return None
+
+            users_to_work_on = [x[0] for x in users_to_work_on]
+
+            # Get how many are left to process, so we can give status on how
+            # far we are in processing
+            sql = "SELECT COUNT(*) FROM " + TEMP_TABLE + "_users"
+            txn.execute(sql)
+            progress["remaining"] = txn.fetchone()[0]
+
+            return users_to_work_on
+
+        users_to_work_on = yield self.db_pool.runInteraction(
+            "populate_user_directory_temp_read", _get_next_batch
+        )
+
+        # No more users -- complete the transaction.
+        if not users_to_work_on:
+            yield self.db_pool.updates._end_background_update(
+                "populate_user_directory_process_users"
+            )
+            return 1
+
+        logger.debug(
+            "Processing the next %d users of %d remaining"
+            % (len(users_to_work_on), progress["remaining"])
+        )
+
+        for user_id in users_to_work_on:
+            profile = yield self.get_profileinfo(get_localpart_from_id(user_id))
+            yield self.update_profile_in_user_dir(
+                user_id, profile.display_name, profile.avatar_url
+            )
+
+            # We've finished processing a user. Delete it from the table.
+            yield self.db_pool.simple_delete_one(
+                TEMP_TABLE + "_users", {"user_id": user_id}
+            )
+            # Update the remaining counter.
+            progress["remaining"] -= 1
+            yield self.db_pool.runInteraction(
+                "populate_user_directory",
+                self.db_pool.updates._background_update_progress_txn,
+                "populate_user_directory_process_users",
+                progress,
+            )
+
+        return len(users_to_work_on)
+
+    @defer.inlineCallbacks
+    def is_room_world_readable_or_publicly_joinable(self, room_id):
+        """Check if the room is either world_readable or publically joinable
+        """
+
+        # Create a state filter that only queries join and history state event
+        types_to_filter = (
+            (EventTypes.JoinRules, ""),
+            (EventTypes.RoomHistoryVisibility, ""),
+        )
+
+        current_state_ids = yield self.get_filtered_current_state_ids(
+            room_id, StateFilter.from_types(types_to_filter)
+        )
+
+        join_rules_id = current_state_ids.get((EventTypes.JoinRules, ""))
+        if join_rules_id:
+            join_rule_ev = yield self.get_event(join_rules_id, allow_none=True)
+            if join_rule_ev:
+                if join_rule_ev.content.get("join_rule") == JoinRules.PUBLIC:
+                    return True
+
+        hist_vis_id = current_state_ids.get((EventTypes.RoomHistoryVisibility, ""))
+        if hist_vis_id:
+            hist_vis_ev = yield self.get_event(hist_vis_id, allow_none=True)
+            if hist_vis_ev:
+                if hist_vis_ev.content.get("history_visibility") == "world_readable":
+                    return True
+
+        return False
+
+    def update_profile_in_user_dir(self, user_id, display_name, avatar_url):
+        """
+        Update or add a user's profile in the user directory.
+        """
+
+        def _update_profile_in_user_dir_txn(txn):
+            new_entry = self.db_pool.simple_upsert_txn(
+                txn,
+                table="user_directory",
+                keyvalues={"user_id": user_id},
+                values={"display_name": display_name, "avatar_url": avatar_url},
+                lock=False,  # We're only inserter
+            )
+
+            if isinstance(self.database_engine, PostgresEngine):
+                # We weight the localpart most highly, then display name and finally
+                # server name
+                if self.database_engine.can_native_upsert:
+                    sql = """
+                        INSERT INTO user_directory_search(user_id, vector)
+                        VALUES (?,
+                            setweight(to_tsvector('english', ?), 'A')
+                            || setweight(to_tsvector('english', ?), 'D')
+                            || setweight(to_tsvector('english', COALESCE(?, '')), 'B')
+                        ) ON CONFLICT (user_id) DO UPDATE SET vector=EXCLUDED.vector
+                    """
+                    txn.execute(
+                        sql,
+                        (
+                            user_id,
+                            get_localpart_from_id(user_id),
+                            get_domain_from_id(user_id),
+                            display_name,
+                        ),
+                    )
+                else:
+                    # TODO: Remove this code after we've bumped the minimum version
+                    # of postgres to always support upserts, so we can get rid of
+                    # `new_entry` usage
+                    if new_entry is True:
+                        sql = """
+                            INSERT INTO user_directory_search(user_id, vector)
+                            VALUES (?,
+                                setweight(to_tsvector('english', ?), 'A')
+                                || setweight(to_tsvector('english', ?), 'D')
+                                || setweight(to_tsvector('english', COALESCE(?, '')), 'B')
+                            )
+                        """
+                        txn.execute(
+                            sql,
+                            (
+                                user_id,
+                                get_localpart_from_id(user_id),
+                                get_domain_from_id(user_id),
+                                display_name,
+                            ),
+                        )
+                    elif new_entry is False:
+                        sql = """
+                            UPDATE user_directory_search
+                            SET vector = setweight(to_tsvector('english', ?), 'A')
+                                || setweight(to_tsvector('english', ?), 'D')
+                                || setweight(to_tsvector('english', COALESCE(?, '')), 'B')
+                            WHERE user_id = ?
+                        """
+                        txn.execute(
+                            sql,
+                            (
+                                get_localpart_from_id(user_id),
+                                get_domain_from_id(user_id),
+                                display_name,
+                                user_id,
+                            ),
+                        )
+                    else:
+                        raise RuntimeError(
+                            "upsert returned None when 'can_native_upsert' is False"
+                        )
+            elif isinstance(self.database_engine, Sqlite3Engine):
+                value = "%s %s" % (user_id, display_name) if display_name else user_id
+                self.db_pool.simple_upsert_txn(
+                    txn,
+                    table="user_directory_search",
+                    keyvalues={"user_id": user_id},
+                    values={"value": value},
+                    lock=False,  # We're only inserter
+                )
+            else:
+                # This should be unreachable.
+                raise Exception("Unrecognized database engine")
+
+            txn.call_after(self.get_user_in_directory.invalidate, (user_id,))
+
+        return self.db_pool.runInteraction(
+            "update_profile_in_user_dir", _update_profile_in_user_dir_txn
+        )
+
+    def add_users_who_share_private_room(self, room_id, user_id_tuples):
+        """Insert entries into the users_who_share_private_rooms table. The first
+        user should be a local user.
+
+        Args:
+            room_id (str)
+            user_id_tuples([(str, str)]): iterable of 2-tuple of user IDs.
+        """
+
+        def _add_users_who_share_room_txn(txn):
+            self.db_pool.simple_upsert_many_txn(
+                txn,
+                table="users_who_share_private_rooms",
+                key_names=["user_id", "other_user_id", "room_id"],
+                key_values=[
+                    (user_id, other_user_id, room_id)
+                    for user_id, other_user_id in user_id_tuples
+                ],
+                value_names=(),
+                value_values=None,
+            )
+
+        return self.db_pool.runInteraction(
+            "add_users_who_share_room", _add_users_who_share_room_txn
+        )
+
+    def add_users_in_public_rooms(self, room_id, user_ids):
+        """Insert entries into the users_who_share_private_rooms table. The first
+        user should be a local user.
+
+        Args:
+            room_id (str)
+            user_ids (list[str])
+        """
+
+        def _add_users_in_public_rooms_txn(txn):
+
+            self.db_pool.simple_upsert_many_txn(
+                txn,
+                table="users_in_public_rooms",
+                key_names=["user_id", "room_id"],
+                key_values=[(user_id, room_id) for user_id in user_ids],
+                value_names=(),
+                value_values=None,
+            )
+
+        return self.db_pool.runInteraction(
+            "add_users_in_public_rooms", _add_users_in_public_rooms_txn
+        )
+
+    def delete_all_from_user_dir(self):
+        """Delete the entire user directory
+        """
+
+        def _delete_all_from_user_dir_txn(txn):
+            txn.execute("DELETE FROM user_directory")
+            txn.execute("DELETE FROM user_directory_search")
+            txn.execute("DELETE FROM users_in_public_rooms")
+            txn.execute("DELETE FROM users_who_share_private_rooms")
+            txn.call_after(self.get_user_in_directory.invalidate_all)
+
+        return self.db_pool.runInteraction(
+            "delete_all_from_user_dir", _delete_all_from_user_dir_txn
+        )
+
+    @cached()
+    def get_user_in_directory(self, user_id):
+        return self.db_pool.simple_select_one(
+            table="user_directory",
+            keyvalues={"user_id": user_id},
+            retcols=("display_name", "avatar_url"),
+            allow_none=True,
+            desc="get_user_in_directory",
+        )
+
+    def update_user_directory_stream_pos(self, stream_id):
+        return self.db_pool.simple_update_one(
+            table="user_directory_stream_pos",
+            keyvalues={},
+            updatevalues={"stream_id": stream_id},
+            desc="update_user_directory_stream_pos",
+        )
+
+
+class UserDirectoryStore(UserDirectoryBackgroundUpdateStore):
+
+    # How many records do we calculate before sending it to
+    # add_users_who_share_private_rooms?
+    SHARE_PRIVATE_WORKING_SET = 500
+
+    def __init__(self, database: DatabasePool, db_conn, hs):
+        super(UserDirectoryStore, self).__init__(database, db_conn, hs)
+
+    def remove_from_user_dir(self, user_id):
+        def _remove_from_user_dir_txn(txn):
+            self.db_pool.simple_delete_txn(
+                txn, table="user_directory", keyvalues={"user_id": user_id}
+            )
+            self.db_pool.simple_delete_txn(
+                txn, table="user_directory_search", keyvalues={"user_id": user_id}
+            )
+            self.db_pool.simple_delete_txn(
+                txn, table="users_in_public_rooms", keyvalues={"user_id": user_id}
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="users_who_share_private_rooms",
+                keyvalues={"user_id": user_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="users_who_share_private_rooms",
+                keyvalues={"other_user_id": user_id},
+            )
+            txn.call_after(self.get_user_in_directory.invalidate, (user_id,))
+
+        return self.db_pool.runInteraction(
+            "remove_from_user_dir", _remove_from_user_dir_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_users_in_dir_due_to_room(self, room_id):
+        """Get all user_ids that are in the room directory because they're
+        in the given room_id
+        """
+        user_ids_share_pub = yield self.db_pool.simple_select_onecol(
+            table="users_in_public_rooms",
+            keyvalues={"room_id": room_id},
+            retcol="user_id",
+            desc="get_users_in_dir_due_to_room",
+        )
+
+        user_ids_share_priv = yield self.db_pool.simple_select_onecol(
+            table="users_who_share_private_rooms",
+            keyvalues={"room_id": room_id},
+            retcol="other_user_id",
+            desc="get_users_in_dir_due_to_room",
+        )
+
+        user_ids = set(user_ids_share_pub)
+        user_ids.update(user_ids_share_priv)
+
+        return user_ids
+
+    def remove_user_who_share_room(self, user_id, room_id):
+        """
+        Deletes entries in the users_who_share_*_rooms table. The first
+        user should be a local user.
+
+        Args:
+            user_id (str)
+            room_id (str)
+        """
+
+        def _remove_user_who_share_room_txn(txn):
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="users_who_share_private_rooms",
+                keyvalues={"user_id": user_id, "room_id": room_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="users_who_share_private_rooms",
+                keyvalues={"other_user_id": user_id, "room_id": room_id},
+            )
+            self.db_pool.simple_delete_txn(
+                txn,
+                table="users_in_public_rooms",
+                keyvalues={"user_id": user_id, "room_id": room_id},
+            )
+
+        return self.db_pool.runInteraction(
+            "remove_user_who_share_room", _remove_user_who_share_room_txn
+        )
+
+    @defer.inlineCallbacks
+    def get_user_dir_rooms_user_is_in(self, user_id):
+        """
+        Returns the rooms that a user is in.
+
+        Args:
+            user_id(str): Must be a local user
+
+        Returns:
+            list: user_id
+        """
+        rows = yield self.db_pool.simple_select_onecol(
+            table="users_who_share_private_rooms",
+            keyvalues={"user_id": user_id},
+            retcol="room_id",
+            desc="get_rooms_user_is_in",
+        )
+
+        pub_rows = yield self.db_pool.simple_select_onecol(
+            table="users_in_public_rooms",
+            keyvalues={"user_id": user_id},
+            retcol="room_id",
+            desc="get_rooms_user_is_in",
+        )
+
+        users = set(pub_rows)
+        users.update(rows)
+        return list(users)
+
+    @defer.inlineCallbacks
+    def get_rooms_in_common_for_users(self, user_id, other_user_id):
+        """Given two user_ids find out the list of rooms they share.
+        """
+        sql = """
+            SELECT room_id FROM (
+                SELECT c.room_id FROM current_state_events AS c
+                INNER JOIN room_memberships AS m USING (event_id)
+                WHERE type = 'm.room.member'
+                    AND m.membership = 'join'
+                    AND state_key = ?
+            ) AS f1 INNER JOIN (
+                SELECT c.room_id FROM current_state_events AS c
+                INNER JOIN room_memberships AS m USING (event_id)
+                WHERE type = 'm.room.member'
+                    AND m.membership = 'join'
+                    AND state_key = ?
+            ) f2 USING (room_id)
+        """
+
+        rows = yield self.db_pool.execute(
+            "get_rooms_in_common_for_users", None, sql, user_id, other_user_id
+        )
+
+        return [room_id for room_id, in rows]
+
+    def get_user_directory_stream_pos(self):
+        return self.db_pool.simple_select_one_onecol(
+            table="user_directory_stream_pos",
+            keyvalues={},
+            retcol="stream_id",
+            desc="get_user_directory_stream_pos",
+        )
+
+    @defer.inlineCallbacks
+    def search_user_dir(self, user_id, search_term, limit):
+        """Searches for users in directory
+
+        Returns:
+            dict of the form::
+
+                {
+                    "limited": <bool>,  # whether there were more results or not
+                    "results": [  # Ordered by best match first
+                        {
+                            "user_id": <user_id>,
+                            "display_name": <display_name>,
+                            "avatar_url": <avatar_url>
+                        }
+                    ]
+                }
+        """
+
+        if self.hs.config.user_directory_search_all_users:
+            join_args = (user_id,)
+            where_clause = "user_id != ?"
+        else:
+            join_args = (user_id,)
+            where_clause = """
+                (
+                    EXISTS (select 1 from users_in_public_rooms WHERE user_id = t.user_id)
+                    OR EXISTS (
+                        SELECT 1 FROM users_who_share_private_rooms
+                        WHERE user_id = ? AND other_user_id = t.user_id
+                    )
+                )
+            """
+
+        if isinstance(self.database_engine, PostgresEngine):
+            full_query, exact_query, prefix_query = _parse_query_postgres(search_term)
+
+            # We order by rank and then if they have profile info
+            # The ranking algorithm is hand tweaked for "best" results. Broadly
+            # the idea is we give a higher weight to exact matches.
+            # The array of numbers are the weights for the various part of the
+            # search: (domain, _, display name, localpart)
+            sql = """
+                SELECT d.user_id AS user_id, display_name, avatar_url
+                FROM user_directory_search as t
+                INNER JOIN user_directory AS d USING (user_id)
+                WHERE
+                    %s
+                    AND vector @@ to_tsquery('english', ?)
+                ORDER BY
+                    (CASE WHEN d.user_id IS NOT NULL THEN 4.0 ELSE 1.0 END)
+                    * (CASE WHEN display_name IS NOT NULL THEN 1.2 ELSE 1.0 END)
+                    * (CASE WHEN avatar_url IS NOT NULL THEN 1.2 ELSE 1.0 END)
+                    * (
+                        3 * ts_rank_cd(
+                            '{0.1, 0.1, 0.9, 1.0}',
+                            vector,
+                            to_tsquery('english', ?),
+                            8
+                        )
+                        + ts_rank_cd(
+                            '{0.1, 0.1, 0.9, 1.0}',
+                            vector,
+                            to_tsquery('english', ?),
+                            8
+                        )
+                    )
+                    DESC,
+                    display_name IS NULL,
+                    avatar_url IS NULL
+                LIMIT ?
+            """ % (
+                where_clause,
+            )
+            args = join_args + (full_query, exact_query, prefix_query, limit + 1)
+        elif isinstance(self.database_engine, Sqlite3Engine):
+            search_query = _parse_query_sqlite(search_term)
+
+            sql = """
+                SELECT d.user_id AS user_id, display_name, avatar_url
+                FROM user_directory_search as t
+                INNER JOIN user_directory AS d USING (user_id)
+                WHERE
+                    %s
+                    AND value MATCH ?
+                ORDER BY
+                    rank(matchinfo(user_directory_search)) DESC,
+                    display_name IS NULL,
+                    avatar_url IS NULL
+                LIMIT ?
+            """ % (
+                where_clause,
+            )
+            args = join_args + (search_query, limit + 1)
+        else:
+            # This should be unreachable.
+            raise Exception("Unrecognized database engine")
+
+        results = yield self.db_pool.execute(
+            "search_user_dir", self.db_pool.cursor_to_dict, sql, *args
+        )
+
+        limited = len(results) > limit
+
+        return {"limited": limited, "results": results}
+
+
+def _parse_query_sqlite(search_term):
+    """Takes a plain unicode string from the user and converts it into a form
+    that can be passed to database.
+    We use this so that we can add prefix matching, which isn't something
+    that is supported by default.
+
+    We specifically add both a prefix and non prefix matching term so that
+    exact matches get ranked higher.
+    """
+
+    # Pull out the individual words, discarding any non-word characters.
+    results = re.findall(r"([\w\-]+)", search_term, re.UNICODE)
+    return " & ".join("(%s* OR %s)" % (result, result) for result in results)
+
+
+def _parse_query_postgres(search_term):
+    """Takes a plain unicode string from the user and converts it into a form
+    that can be passed to database.
+    We use this so that we can add prefix matching, which isn't something
+    that is supported by default.
+    """
+
+    # Pull out the individual words, discarding any non-word characters.
+    results = re.findall(r"([\w\-]+)", search_term, re.UNICODE)
+
+    both = " & ".join("(%s:* | %s)" % (result, result) for result in results)
+    exact = " & ".join("%s" % (result,) for result in results)
+    prefix = " & ".join("%s:*" % (result,) for result in results)
+
+    return both, exact, prefix
diff --git a/synapse/storage/databases/main/user_erasure_store.py b/synapse/storage/databases/main/user_erasure_store.py
new file mode 100644
index 0000000000..ab6cb2c1f6
--- /dev/null
+++ b/synapse/storage/databases/main/user_erasure_store.py
@@ -0,0 +1,113 @@
+# -*- coding: utf-8 -*-
+# Copyright 2018 New Vector Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import operator
+
+from synapse.storage._base import SQLBaseStore
+from synapse.util.caches.descriptors import cached, cachedList
+
+
+class UserErasureWorkerStore(SQLBaseStore):
+    @cached()
+    def is_user_erased(self, user_id):
+        """
+        Check if the given user id has requested erasure
+
+        Args:
+            user_id (str): full user id to check
+
+        Returns:
+            Deferred[bool]: True if the user has requested erasure
+        """
+        return self.db_pool.simple_select_onecol(
+            table="erased_users",
+            keyvalues={"user_id": user_id},
+            retcol="1",
+            desc="is_user_erased",
+        ).addCallback(operator.truth)
+
+    @cachedList(
+        cached_method_name="is_user_erased", list_name="user_ids", inlineCallbacks=True
+    )
+    def are_users_erased(self, user_ids):
+        """
+        Checks which users in a list have requested erasure
+
+        Args:
+            user_ids (iterable[str]): full user id to check
+
+        Returns:
+            Deferred[dict[str, bool]]:
+                for each user, whether the user has requested erasure.
+        """
+        # this serves the dual purpose of (a) making sure we can do len and
+        # iterate it multiple times, and (b) avoiding duplicates.
+        user_ids = tuple(set(user_ids))
+
+        rows = yield self.db_pool.simple_select_many_batch(
+            table="erased_users",
+            column="user_id",
+            iterable=user_ids,
+            retcols=("user_id",),
+            desc="are_users_erased",
+        )
+        erased_users = {row["user_id"] for row in rows}
+
+        res = {u: u in erased_users for u in user_ids}
+        return res
+
+
+class UserErasureStore(UserErasureWorkerStore):
+    def mark_user_erased(self, user_id: str) -> None:
+        """Indicate that user_id wishes their message history to be erased.
+
+        Args:
+            user_id: full user_id to be erased
+        """
+
+        def f(txn):
+            # first check if they are already in the list
+            txn.execute("SELECT 1 FROM erased_users WHERE user_id = ?", (user_id,))
+            if txn.fetchone():
+                return
+
+            # they are not already there: do the insert.
+            txn.execute("INSERT INTO erased_users (user_id) VALUES (?)", (user_id,))
+
+            self._invalidate_cache_and_stream(txn, self.is_user_erased, (user_id,))
+
+        return self.db_pool.runInteraction("mark_user_erased", f)
+
+    def mark_user_not_erased(self, user_id: str) -> None:
+        """Indicate that user_id is no longer erased.
+
+        Args:
+            user_id: full user_id to be un-erased
+        """
+
+        def f(txn):
+            # first check if they are already in the list
+            txn.execute("SELECT 1 FROM erased_users WHERE user_id = ?", (user_id,))
+            if not txn.fetchone():
+                return
+
+            # They are there, delete them.
+            self.simple_delete_one_txn(
+                txn, "erased_users", keyvalues={"user_id": user_id}
+            )
+
+            self._invalidate_cache_and_stream(txn, self.is_user_erased, (user_id,))
+
+        return self.db_pool.runInteraction("mark_user_not_erased", f)