diff options
Diffstat (limited to 'src/backend/optimizer/plan/createplan.c')
| -rw-r--r-- | src/backend/optimizer/plan/createplan.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c index 6b784cd75c1..109a0145475 100644 --- a/src/backend/optimizer/plan/createplan.c +++ b/src/backend/optimizer/plan/createplan.c @@ -10,7 +10,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.239 2008/04/13 20:51:20 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/plan/createplan.c,v 1.240 2008/04/17 21:22:14 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -115,6 +115,7 @@ static MergeJoin *make_mergejoin(List *tlist, static Sort *make_sort(PlannerInfo *root, Plan *lefttree, int numCols, AttrNumber *sortColIdx, Oid *sortOperators, bool *nullsFirst, double limit_tuples); +static Material *make_material(Plan *lefttree); /* @@ -616,12 +617,14 @@ create_unique_plan(PlannerInfo *root, UniquePath *best_path) * add any such expressions to the subplan's tlist. * * The subplan may have a "physical" tlist if it is a simple scan plan. - * This should be left as-is if we don't need to add any expressions; + * If we're going to sort, this should be reduced to the regular tlist, + * so that we don't sort more data than we need to. For hashing, the + * tlist should be left as-is if we don't need to add any expressions; * but if we do have to add expressions, then a projection step will be - * needed at runtime anyway, and so we may as well remove unneeded items. + * needed at runtime anyway, so we may as well remove unneeded items. * Therefore newtlist starts from build_relation_tlist() not just a * copy of the subplan's tlist; and we don't install it into the subplan - * unless stuff has to be added. + * unless we are sorting or stuff has to be added. * * To find the correct list of values to unique-ify, we look in the * information saved for IN expressions. If this code is ever used in @@ -669,7 +672,7 @@ create_unique_plan(PlannerInfo *root, UniquePath *best_path) } } - if (newitems) + if (newitems || best_path->umethod == UNIQUE_PATH_SORT) { /* * If the top plan node can't do projections, we need to add a Result @@ -2850,7 +2853,7 @@ make_sort_from_groupcols(PlannerInfo *root, sortColIdx, sortOperators, nullsFirst, -1.0); } -Material * +static Material * make_material(Plan *lefttree) { Material *node = makeNode(Material); |