From 3d99a81397abb8bb7b95aee794d6644e174e174f Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Wed, 12 Jun 2019 19:42:38 -0400 Subject: Fix incorrect printing of queries with duplicated join names. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Given a query in which multiple JOIN nodes used the same alias (which'd necessarily be in different sub-SELECTs), ruleutils.c would assign the JOIN nodes distinct aliases for clarity ... but then it forgot to print the modified aliases when dumping the JOIN nodes themselves. This results in a dump/reload hazard for views, because the emitted query is flat-out incorrect: Vars will be printed with table names that have no referent. This has been wrong for a long time, so back-patch to all supported branches. Philip Dubé Discussion: https://postgr.es/m/CY4PR2101MB080246F2955FF58A6ED1FEAC98140@CY4PR2101MB0802.namprd21.prod.outlook.com --- src/backend/utils/adt/ruleutils.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'src/backend/utils/adt/ruleutils.c') diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c index 9dda4820afd..b9fdd99db8e 100644 --- a/src/backend/utils/adt/ruleutils.c +++ b/src/backend/utils/adt/ruleutils.c @@ -10309,8 +10309,16 @@ get_from_clause_item(Node *jtnode, Query *query, deparse_context *context) /* Yes, it's correct to put alias after the right paren ... */ if (j->alias != NULL) { + /* + * Note that it's correct to emit an alias clause if and only if + * there was one originally. Otherwise we'd be converting a named + * join to unnamed or vice versa, which creates semantic + * subtleties we don't want. However, we might print a different + * alias name than was there originally. + */ appendStringInfo(buf, " %s", - quote_identifier(j->alias->aliasname)); + quote_identifier(get_rtable_name(j->rtindex, + context))); get_column_alias_list(colinfo, context); } } -- cgit v1.2.3