diff options
| -rw-r--r-- | synapse/storage/state.py | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/synapse/storage/state.py b/synapse/storage/state.py index 0730399b80..d6643473db 100644 --- a/synapse/storage/state.py +++ b/synapse/storage/state.py @@ -315,6 +315,10 @@ class StateStore(SQLBaseStore): # against `state_groups_state` to fetch the latest state. # It assumes that previous state groups are always numerically # lesser. + # The PARTITION is used to get the event_id in the greatest state + # group for the given type, state_key. + # This may return multiple rows per (type, state_key), but last_value + # should be the same. sql = (""" WITH RECURSIVE state(state_group) AS ( VALUES(?::bigint) @@ -322,11 +326,12 @@ class StateStore(SQLBaseStore): SELECT prev_state_group FROM state_group_edges e, state s WHERE s.state_group = e.state_group ) - SELECT type, state_key, event_id FROM state_groups_state - WHERE ROW(type, state_key, state_group) IN ( - SELECT type, state_key, max(state_group) FROM state - INNER JOIN state_groups_state USING (state_group) - GROUP BY type, state_key + SELECT type, state_key, last_value(event_id) OVER ( + PARTITION BY type, state_key ORDER BY state_group ASC + ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING + ) AS event_id FROM state_groups_state + WHERE state_group IN ( + SELECT state_group FROM state ) %s; """) % (where_clause,) |