diff options
Diffstat (limited to 'src/backend/optimizer/util/plancat.c')
| -rw-r--r-- | src/backend/optimizer/util/plancat.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index b799e249db8..7c4cd8a7f9c 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -1421,7 +1421,11 @@ relation_excluded_by_constraints(PlannerInfo *root, safe_restrictions = lappend(safe_restrictions, rinfo->clause); } - if (predicate_refuted_by(safe_restrictions, safe_restrictions, false)) + /* + * We can use weak refutation here, since we're comparing restriction + * clauses with restriction clauses. + */ + if (predicate_refuted_by(safe_restrictions, safe_restrictions, true)) return true; /* @@ -1469,6 +1473,9 @@ relation_excluded_by_constraints(PlannerInfo *root, * an obvious optimization. Some of the clauses might be OR clauses that * have volatile and nonvolatile subclauses, and it's OK to make * deductions with the nonvolatile parts. + * + * We need strong refutation because we have to prove that the constraints + * would yield false, not just NULL. */ if (predicate_refuted_by(safe_constraints, rel->baserestrictinfo, false)) return true; |