diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/optimizer/plan/planner.c | 3 | ||||
| -rw-r--r-- | src/backend/optimizer/util/pathnode.c | 45 | ||||
| -rw-r--r-- | src/test/regress/expected/select_parallel.out | 25 | ||||
| -rw-r--r-- | src/test/regress/sql/select_parallel.sql | 13 |
4 files changed, 69 insertions, 17 deletions
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 607f7cd2518..90fd9cc9598 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -5060,7 +5060,8 @@ create_ordered_paths(PlannerInfo *root, path = (Path *) create_gather_merge_path(root, ordered_rel, path, - target, root->sort_pathkeys, NULL, + path->pathtarget, + root->sort_pathkeys, NULL, &total_groups); /* Add projection step if needed */ diff --git a/src/backend/optimizer/util/pathnode.c b/src/backend/optimizer/util/pathnode.c index 36ec025b05b..68dee0f5010 100644 --- a/src/backend/optimizer/util/pathnode.c +++ b/src/backend/optimizer/util/pathnode.c @@ -2368,9 +2368,9 @@ create_projection_path(PlannerInfo *root, * knows that the given path isn't referenced elsewhere and so can be modified * in-place. * - * If the input path is a GatherPath, we try to push the new target down to - * its input as well; this is a yet more invasive modification of the input - * path, which create_projection_path() can't do. + * If the input path is a GatherPath or GatherMergePath, we try to push the + * new target down to its input as well; this is a yet more invasive + * modification of the input path, which create_projection_path() can't do. * * Note that we mustn't change the source path's parent link; so when it is * add_path'd to "rel" things will be a bit inconsistent. So far that has @@ -2407,31 +2407,44 @@ apply_projection_to_path(PlannerInfo *root, (target->cost.per_tuple - oldcost.per_tuple) * path->rows; /* - * If the path happens to be a Gather path, we'd like to arrange for the - * subpath to return the required target list so that workers can help - * project. But if there is something that is not parallel-safe in the - * target expressions, then we can't. + * If the path happens to be a Gather or GatherMerge path, we'd like to + * arrange for the subpath to return the required target list so that + * workers can help project. But if there is something that is not + * parallel-safe in the target expressions, then we can't. */ - if (IsA(path, GatherPath) && + if ((IsA(path, GatherPath) || IsA(path, GatherMergePath)) && is_parallel_safe(root, (Node *) target->exprs)) { - GatherPath *gpath = (GatherPath *) path; - /* * We always use create_projection_path here, even if the subpath is * projection-capable, so as to avoid modifying the subpath in place. * It seems unlikely at present that there could be any other * references to the subpath, but better safe than sorry. * - * Note that we don't change the GatherPath's cost estimates; it might + * Note that we don't change the parallel path's cost estimates; it might * be appropriate to do so, to reflect the fact that the bulk of the * target evaluation will happen in workers. */ - gpath->subpath = (Path *) - create_projection_path(root, - gpath->subpath->parent, - gpath->subpath, - target); + if (IsA(path, GatherPath)) + { + GatherPath *gpath = (GatherPath *) path; + + gpath->subpath = (Path *) + create_projection_path(root, + gpath->subpath->parent, + gpath->subpath, + target); + } + else + { + GatherMergePath *gmpath = (GatherMergePath *) path; + + gmpath->subpath = (Path *) + create_projection_path(root, + gmpath->subpath->parent, + gmpath->subpath, + target); + } } else if (path->parallel_safe && !is_parallel_safe(root, (Node *) target->exprs)) diff --git a/src/test/regress/expected/select_parallel.out b/src/test/regress/expected/select_parallel.out index ac9ad0668d1..6f04769e3ea 100644 --- a/src/test/regress/expected/select_parallel.out +++ b/src/test/regress/expected/select_parallel.out @@ -375,6 +375,31 @@ select count(*) from tenk1 group by twenty; 500 (20 rows) +--test expressions in targetlist are pushed down for gather merge +create or replace function simple_func(var1 integer) returns integer +as $$ +begin + return var1 + 10; +end; +$$ language plpgsql PARALLEL SAFE; +explain (costs off, verbose) + select ten, simple_func(ten) from tenk1 where ten < 100 order by ten; + QUERY PLAN +----------------------------------------------------- + Gather Merge + Output: ten, (simple_func(ten)) + Workers Planned: 4 + -> Result + Output: ten, simple_func(ten) + -> Sort + Output: ten + Sort Key: tenk1.ten + -> Parallel Seq Scan on public.tenk1 + Output: ten + Filter: (tenk1.ten < 100) +(11 rows) + +drop function simple_func(integer); --test rescan behavior of gather merge set enable_material = false; explain (costs off) diff --git a/src/test/regress/sql/select_parallel.sql b/src/test/regress/sql/select_parallel.sql index 495f0335dcc..9c1b87abdfc 100644 --- a/src/test/regress/sql/select_parallel.sql +++ b/src/test/regress/sql/select_parallel.sql @@ -144,6 +144,19 @@ explain (costs off) select count(*) from tenk1 group by twenty; +--test expressions in targetlist are pushed down for gather merge +create or replace function simple_func(var1 integer) returns integer +as $$ +begin + return var1 + 10; +end; +$$ language plpgsql PARALLEL SAFE; + +explain (costs off, verbose) + select ten, simple_func(ten) from tenk1 where ten < 100 order by ten; + +drop function simple_func(integer); + --test rescan behavior of gather merge set enable_material = false; |