From 1cbc17aaca82b2e262912da96c49b2e1d2f492e7 Mon Sep 17 00:00:00 2001 From: Robert Haas Date: Fri, 1 Dec 2017 10:58:08 -0500 Subject: [PATCH] Try to exclude partitioned tables in toto. Ashutosh Bapat, reviewed by Jeevan Chalke. Comment by me. Discussion: http://postgr.es/m/CAFjFpRcuRaydz88CY_aQekmuvmN2A9ax5z0k=ppT+s8KS8xMRA@mail.gmail.com --- src/backend/optimizer/util/plancat.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index 199a2631a1..f7438714c4 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -1414,8 +1414,18 @@ relation_excluded_by_constraints(PlannerInfo *root, if (predicate_refuted_by(safe_restrictions, safe_restrictions, false)) return true; - /* Only plain relations have constraints */ - if (rte->rtekind != RTE_RELATION || rte->inh) + /* + * Only plain relations have constraints. In a partitioning hierarchy, + * but not with regular table inheritance, it's OK to assume that any + * constraints that hold for the parent also hold for every child; for + * instance, table inheritance allows the parent to have constraints + * marked NO INHERIT, but table partitioning does not. We choose to check + * whether the partitioning parents can be excluded here; doing so + * consumes some cycles, but potentially saves us the work of excluding + * each child individually. + */ + if (rte->rtekind != RTE_RELATION || + (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)) return false; /* -- 2.40.0