From f18d7546c63ae30c4058d1ec6ab2d5c3b001d257 Mon Sep 17 00:00:00 2001 From: Mark Haines Date: Mon, 4 Jul 2016 15:48:25 +0100 Subject: [PATCH] Use a query that postgresql optimises better for get_events_around --- synapse/storage/stream.py | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/synapse/storage/stream.py b/synapse/storage/stream.py index b9ad965fd..4dd11284e 100644 --- a/synapse/storage/stream.py +++ b/synapse/storage/stream.py @@ -591,25 +591,28 @@ class StreamStore(SQLBaseStore): query_before = ( "SELECT topological_ordering, stream_ordering, event_id FROM events" - " WHERE room_id = ? AND (topological_ordering < ?" - " OR (topological_ordering = ? AND stream_ordering < ?))" - " ORDER BY topological_ordering DESC, stream_ordering DESC" - " LIMIT ?" + " WHERE room_id = ? AND topological_ordering < ?" + " UNION ALL " + " SELECT topological_ordering, stream_ordering, event_id FROM events" + " WHERE room_id = ? AND topological_ordering = ? AND stream_ordering < ?" + " ORDER BY topological_ordering DESC, stream_ordering DESC LIMIT ?" ) query_after = ( "SELECT topological_ordering, stream_ordering, event_id FROM events" - " WHERE room_id = ? AND (topological_ordering > ?" - " OR (topological_ordering = ? AND stream_ordering > ?))" - " ORDER BY topological_ordering ASC, stream_ordering ASC" - " LIMIT ?" + " WHERE room_id = ? AND topological_ordering > ?" + " UNION ALL" + " SELECT topological_ordering, stream_ordering, event_id FROM events" + " WHERE room_id = ? AND topological_ordering = ? AND stream_ordering > ?" + " ORDER BY topological_ordering ASC, stream_ordering ASC LIMIT ?" ) txn.execute( query_before, ( - room_id, topological_ordering, topological_ordering, - stream_ordering, before_limit, + room_id, topological_ordering, + room_id, topological_ordering, stream_ordering, + before_limit, ) ) @@ -630,8 +633,9 @@ class StreamStore(SQLBaseStore): txn.execute( query_after, ( - room_id, topological_ordering, topological_ordering, - stream_ordering, after_limit, + room_id, topological_ordering, + room_id, topological_ordering, stream_ordering, + after_limit, ) )