diff options
Diffstat (limited to 'src/backend/optimizer/plan/planner.c')
| -rw-r--r-- | src/backend/optimizer/plan/planner.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 6b24098cdd3..5de096e8319 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.261 2009/10/28 14:55:38 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/plan/planner.c,v 1.262 2009/12/15 17:57:46 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -1096,11 +1096,12 @@ grouping_planner(PlannerInfo *root, double tuple_fraction) bool can_sort; /* - * Executor doesn't support hashed aggregation with DISTINCT - * aggregates. (Doing so would imply storing *all* the input - * values in the hash table, which seems like a certain loser.) + * Executor doesn't support hashed aggregation with DISTINCT or + * ORDER BY aggregates. (Doing so would imply storing *all* the + * input values in the hash table, and/or running many sorts in + * parallel, either of which seems like a certain loser.) */ - can_hash = (agg_counts.numDistinctAggs == 0 && + can_hash = (agg_counts.numOrderedAggs == 0 && grouping_is_hashable(parse->groupClause)); can_sort = grouping_is_sortable(parse->groupClause); if (can_hash && can_sort) |