From 18661c67e96ff4a81ab3844843a73676d161db0c Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 23 Oct 2011 00:43:45 -0400 Subject: Don't trust deferred-unique indexes for join removal. The uniqueness condition might fail to hold intra-transaction, and assuming it does can give incorrect query results. Per report from Marti Raudsepp, though this is not his proposed patch. Back-patch to 9.0, where both these features were introduced. In the released branches, add the new IndexOptInfo field to the end of the struct, to try to minimize ABI breakage for third-party code that may be examining that struct. --- src/backend/optimizer/path/indxpath.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'src/backend/optimizer/path/indxpath.c') diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c index fc96f4f1dac..58b8797b738 100644 --- a/src/backend/optimizer/path/indxpath.c +++ b/src/backend/optimizer/path/indxpath.c @@ -2179,10 +2179,11 @@ relation_has_unique_index_for(PlannerInfo *root, RelOptInfo *rel, int c; /* - * If the index is not unique or if it's a partial index that doesn't - * match the query, it's useless here. + * If the index is not unique, or not immediately enforced, or if it's + * a partial index that doesn't match the query, it's useless here. */ - if (!ind->unique || (ind->indpred != NIL && !ind->predOK)) + if (!ind->unique || !ind->immediate || + (ind->indpred != NIL && !ind->predOK)) continue; /* -- cgit v1.2.3