Revert "Reintroduce membership tables event stream ordering (#15128)" (#15347)

This reverts commit e6af49fbea939d9e69ed05e0a0ced5948c722ea4.

2 files changed, 0 insertions, 99 deletions

diff --git a/synapse/storage/schema/main/delta/74/01membership_tables_event_stream_ordering.sql b/synapse/storage/schema/main/delta/74/01membership_tables_event_stream_ordering.sql
deleted file mode 100644
index e2608f3a2e..0000000000
--- a/synapse/storage/schema/main/delta/74/01membership_tables_event_stream_ordering.sql
+++ /dev/null
@@ -1,20 +0,0 @@
-/* Copyright 2022 Beeper
- *
- * 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.
- */
-
--- Each of these are denormalised copies of `stream_ordering` from the corresponding row in` events` which
--- we use to improve database performance by reduring JOINs.
-ALTER TABLE current_state_events ADD COLUMN event_stream_ordering BIGINT REFERENCES events(stream_ordering);
-ALTER TABLE local_current_membership ADD COLUMN event_stream_ordering BIGINT REFERENCES events(stream_ordering);
-ALTER TABLE room_memberships ADD COLUMN event_stream_ordering BIGINT REFERENCES events(stream_ordering);
diff --git a/synapse/storage/schema/main/delta/74/02membership_tables_event_stream_ordering_triggers.py b/synapse/storage/schema/main/delta/74/02membership_tables_event_stream_ordering_triggers.py
deleted file mode 100644
index e32e9083b3..0000000000
--- a/synapse/storage/schema/main/delta/74/02membership_tables_event_stream_ordering_triggers.py
+++ /dev/null
@@ -1,79 +0,0 @@
-# Copyright 2022 Beeper
-#
-# 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 adds triggers to the room membership tables to enforce consistency.
-Triggers cannot be expressed in .sql files, so we have to use a separate file.
-"""
-from synapse.storage.engines import BaseDatabaseEngine, PostgresEngine, Sqlite3Engine
-from synapse.storage.types import Cursor
-
-
-def run_create(cur: Cursor, database_engine: BaseDatabaseEngine, *args, **kwargs):
-    # Complain if the `event_stream_ordering` in membership tables doesn't match
-    # the `stream_ordering` row with the same `event_id` in `events`.
-    if isinstance(database_engine, Sqlite3Engine):
-        for table in (
-            "current_state_events",
-            "local_current_membership",
-            "room_memberships",
-        ):
-            cur.execute(
-                f"""
-                CREATE TRIGGER IF NOT EXISTS {table}_bad_event_stream_ordering
-                BEFORE INSERT ON {table}
-                FOR EACH ROW
-                BEGIN
-                    SELECT RAISE(ABORT, 'Incorrect event_stream_ordering in {table}')
-                    WHERE EXISTS (
-                        SELECT 1 FROM events
-                        WHERE events.event_id = NEW.event_id
-                           AND events.stream_ordering != NEW.event_stream_ordering
-                    );
-                END;
-                """
-            )
-    elif isinstance(database_engine, PostgresEngine):
-        cur.execute(
-            """
-            CREATE OR REPLACE FUNCTION check_event_stream_ordering() RETURNS trigger AS $BODY$
-            BEGIN
-                IF EXISTS (
-                    SELECT 1 FROM events
-                    WHERE events.event_id = NEW.event_id
-                       AND events.stream_ordering != NEW.event_stream_ordering
-                ) THEN
-                    RAISE EXCEPTION 'Incorrect event_stream_ordering';
-                END IF;
-                RETURN NEW;
-            END;
-            $BODY$ LANGUAGE plpgsql;
-            """
-        )
-
-        for table in (
-            "current_state_events",
-            "local_current_membership",
-            "room_memberships",
-        ):
-            cur.execute(
-                f"""
-                CREATE TRIGGER check_event_stream_ordering BEFORE INSERT OR UPDATE ON {table}
-                FOR EACH ROW
-                EXECUTE PROCEDURE check_event_stream_ordering()
-                """
-            )
-    else:
-        raise NotImplementedError("Unknown database engine")