From 028a0c5a2913f18c954845cc014786912f39fa30 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Tue, 9 Aug 2011 00:48:58 -0400 Subject: Fix nested PlaceHolderVar expressions that appear only in targetlists. A PlaceHolderVar's expression might contain another, lower-level PlaceHolderVar. If the outer PlaceHolderVar is used, the inner one certainly will be also, and so we have to make sure that both of them get into the placeholder_list with correct ph_may_need values during the initial pre-scan of the query (before deconstruct_jointree starts). We did this correctly for PlaceHolderVars appearing in the query quals, but overlooked the issue for those appearing in the top-level targetlist; with the result that nested placeholders referenced only in the targetlist did not work correctly, as illustrated in bug #6154. While at it, add some error checking to find_placeholder_info to ensure that we don't try to create new placeholders after it's too late to do so; they have to all be created before deconstruct_jointree starts. Back-patch to 8.4 where the PlaceHolderVar mechanism was introduced. --- src/backend/optimizer/path/equivclass.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/backend/optimizer/path/equivclass.c') diff --git a/src/backend/optimizer/path/equivclass.c b/src/backend/optimizer/path/equivclass.c index f2beb410e73..acc4fb1a185 100644 --- a/src/backend/optimizer/path/equivclass.c +++ b/src/backend/optimizer/path/equivclass.c @@ -850,7 +850,7 @@ generate_base_implied_equalities_no_const(PlannerInfo *root, PVC_RECURSE_AGGREGATES, PVC_INCLUDE_PLACEHOLDERS); - add_vars_to_targetlist(root, vars, ec->ec_relids); + add_vars_to_targetlist(root, vars, ec->ec_relids, false); list_free(vars); } } -- cgit v1.2.3