diff options
Diffstat (limited to 'src/backend/optimizer/plan/planner.c')
| -rw-r--r-- | src/backend/optimizer/plan/planner.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c index 07301c77fbf..620888cbb86 100644 --- a/src/backend/optimizer/plan/planner.c +++ b/src/backend/optimizer/plan/planner.c @@ -341,13 +341,22 @@ subquery_planner(PlannerGlobal *glob, Query *parse, inline_set_returning_functions(root); /* - * Check to see if any subqueries in the rangetable can be merged into + * Check to see if any subqueries in the jointree can be merged into * this query. */ parse->jointree = (FromExpr *) pull_up_subqueries(root, (Node *) parse->jointree, NULL, NULL); /* + * If this is a simple UNION ALL query, flatten it into an appendrel. + * We do this now because it requires applying pull_up_subqueries to the + * leaf queries of the UNION ALL, which weren't touched above because they + * weren't referenced by the jointree (they will be after we do this). + */ + if (parse->setOperations) + flatten_simple_union_all(root); + + /* * Detect whether any rangetable entries are RTE_JOIN kind; if not, we can * avoid the expense of doing flatten_join_alias_vars(). Also check for * outer joins --- if none, we can skip reduce_outer_joins(). This must be |