diff --git a/src/github.com/matrix-org/dendrite/syncserver/storage/output_room_events_table.go b/src/github.com/matrix-org/dendrite/syncserver/storage/output_room_events_table.go
index 9f2e3b4a9..5d9fba9b4 100644
--- a/src/github.com/matrix-org/dendrite/syncserver/storage/output_room_events_table.go
+++ b/src/github.com/matrix-org/dendrite/syncserver/storage/output_room_events_table.go
@@ -50,7 +50,7 @@ const selectMaxIDSQL = "" +
 // In order for us to apply the state updates correctly, rows need to be ordered in the order they were received (id).
 const selectStateInRangeSQL = "" +
 	"SELECT event_json, add_state_ids, remove_state_ids FROM output_room_events" +
-	" WHERE id > $1 AND id < $2 AND add_state_ids IS NOT NULL OR remove_state_ids IS NOT NULL" +
+	" WHERE (id > $1 AND id < $2) AND (add_state_ids IS NOT NULL OR remove_state_ids IS NOT NULL)" +
 	" ORDER BY id ASC"
 
 type outputRoomEventsStatements struct {