From 317aba70ef83464c0e592be733e38e4b8897c0b5 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 12 Mar 2025 11:27:59 -0400 Subject: [PATCH] Preserve RangeTblEntry.relid when expanding a view RTE. When the rewriter converts an RTE_RELATION RTE for a view into an RTE_SUBQUERY RTE containing the view's defining query, leave the relid field alone instead of zeroing it. This allows the planner to tell that the subquery came from a view rather than having been written in-line, which is needed to support an upcoming planner bug fix. We cannot change the behavior of the outfuncs/readfuncs code in released branches, so the relid field will not survive in plans passed to parallel workers; therefore this info should not be relied on in the executor. This back-patches a portion of the data structure definitional changes made in v16 and up by commit 47bb9db75. It's being committed separately for visibility in the commit log, but with luck it will not actually matter to anyone. While it's not inconceivable that this change will break code expecting relid to be zero in a subquery RTE, we can hope that such code has already been adjusted to cope with v16 and up. Reported-by: Duncan Sands Diagnosed-by: Tender Wang Author: Tom Lane Reviewed-by: Dean Rasheed Discussion: https://postgr.es/m/3518c50a-ab18-482f-b916-a37263622501@deepbluecap.com Backpatch-through: 13-15 --- src/backend/rewrite/rewriteHandler.c | 8 ++++++-- src/include/nodes/parsenodes.h | 6 ++++++ 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/src/backend/rewrite/rewriteHandler.c b/src/backend/rewrite/rewriteHandler.c index d2a0e501d1e..30ae22e43df 100644 --- a/src/backend/rewrite/rewriteHandler.c +++ b/src/backend/rewrite/rewriteHandler.c @@ -1859,8 +1859,12 @@ ApplyRetrieveRule(Query *parsetree, rte->rtekind = RTE_SUBQUERY; rte->subquery = rule_action; rte->security_barrier = RelationIsSecurityView(relation); - /* Clear fields that should not be set in a subquery RTE */ - rte->relid = InvalidOid; + + /* + * Clear fields that should not be set in a subquery RTE. However, we + * retain the relid to support correct operation of makeWholeRowVar during + * planning. + */ rte->relkind = 0; rte->rellockmode = 0; rte->tablesample = NULL; diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index 6944362c7ac..abc87c59e6f 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -1017,6 +1017,12 @@ typedef struct RangeTblEntry /* * Fields valid for a plain relation RTE (else zero): * + * As a special case, relid can also be set in RTE_SUBQUERY RTEs. This + * happens when an RTE_RELATION RTE for a view is transformed to an + * RTE_SUBQUERY during rewriting. We keep the relid because it is useful + * during planning, cf makeWholeRowVar. (It cannot be relied on during + * execution, because it will not propagate to parallel workers.) + * * As a special case, RTE_NAMEDTUPLESTORE can also set relid to indicate * that the tuple format of the tuplestore is the same as the referenced * relation. This allows plans referencing AFTER trigger transition