diff options
Diffstat (limited to 'src/backend/optimizer/plan')
| -rw-r--r-- | src/backend/optimizer/plan/planner.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 80ad6bf..2ffef1b 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -7349,13 +7349,24 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel) { ListCell *lc; Path *cheapest_partial_path; + List *groupby_pathkeys; + + /* + * This occurs after any partial aggregation has taken place, so trim off + * any pathkeys added for ORDER BY / DISTINCT aggregates. + */ + if (list_length(root->group_pathkeys) > root->num_groupby_pathkeys) + groupby_pathkeys = list_copy_head(root->group_pathkeys, + root->num_groupby_pathkeys); + else + groupby_pathkeys = root->group_pathkeys; /* Try Gather for unordered paths and Gather Merge for ordered ones. */ generate_useful_gather_paths(root, rel, true); /* Try cheapest partial path + explicit Sort + Gather Merge. */ cheapest_partial_path = linitial(rel->partial_pathlist); - if (!pathkeys_contained_in(root->group_pathkeys, + if (!pathkeys_contained_in(groupby_pathkeys, cheapest_partial_path->pathkeys)) { Path *path; @@ -7364,14 +7375,14 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel) total_groups = cheapest_partial_path->rows * cheapest_partial_path->parallel_workers; path = (Path *) create_sort_path(root, rel, cheapest_partial_path, - root->group_pathkeys, + groupby_pathkeys, -1.0); path = (Path *) create_gather_merge_path(root, rel, path, rel->reltarget, - root->group_pathkeys, + groupby_pathkeys, NULL, &total_groups); @@ -7382,10 +7393,10 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel) * Consider incremental sort on all partial paths, if enabled. * * We can also skip the entire loop when we only have a single-item - * group_pathkeys because then we can't possibly have a presorted prefix + * groupby_pathkeys because then we can't possibly have a presorted prefix * of the list without having the list be fully sorted. */ - if (!enable_incremental_sort || list_length(root->group_pathkeys) == 1) + if (!enable_incremental_sort || list_length(groupby_pathkeys) == 1) return; /* also consider incremental sort on partial paths, if enabled */ @@ -7396,7 +7407,7 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel) int presorted_keys; double total_groups; - is_sorted = pathkeys_count_contained_in(root->group_pathkeys, + is_sorted = pathkeys_count_contained_in(groupby_pathkeys, path->pathkeys, &presorted_keys); @@ -7409,7 +7420,7 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel) path = (Path *) create_incremental_sort_path(root, rel, path, - root->group_pathkeys, + groupby_pathkeys, presorted_keys, -1.0); @@ -7418,7 +7429,7 @@ gather_grouping_paths(PlannerInfo *root, RelOptInfo *rel) rel, path, rel->reltarget, - root->group_pathkeys, + groupby_pathkeys, NULL, &total_groups); |