From c7468c73f7b6e842a53c12eaee5578a76a8fa7a6 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Mon, 13 Feb 2023 12:19:58 -0500 Subject: [PATCH] Fix buggy recursion in flatten_rtes_walker(). Must save-and-restore the context we are modifying. Oversight in commit a61b1f748. Tender Wang Discussion: https://postgr.es/m/CAHewXNnnNySD_YcKNuFpQDV2gxWA7_YLWqHmYVcyoOYxn8kY2A@mail.gmail.com Discussion: https://postgr.es/m/20230212233711.GA1316@telsasoft.com --- src/backend/optimizer/plan/setrefs.c | 13 +++++++++---- src/test/regress/expected/join.out | 12 ++++++++++++ src/test/regress/sql/join.sql | 6 ++++++ 3 files changed, 27 insertions(+), 4 deletions(-) diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c index 186fc8014b620..5cc8366af6685 100644 --- a/src/backend/optimizer/plan/setrefs.c +++ b/src/backend/optimizer/plan/setrefs.c @@ -536,11 +536,16 @@ flatten_rtes_walker(Node *node, flatten_rtes_walker_context *cxt) * Recurse into subselects. Must update cxt->query to this query so * that the rtable and rteperminfos correspond with each other. */ + Query *save_query = cxt->query; + bool result; + cxt->query = (Query *) node; - return query_tree_walker((Query *) node, - flatten_rtes_walker, - (void *) cxt, - QTW_EXAMINE_RTES_BEFORE); + result = query_tree_walker((Query *) node, + flatten_rtes_walker, + (void *) cxt, + QTW_EXAMINE_RTES_BEFORE); + cxt->query = save_query; + return result; } return expression_tree_walker(node, flatten_rtes_walker, (void *) cxt); diff --git a/src/test/regress/expected/join.out b/src/test/regress/expected/join.out index db9512969f373..16318d9da22d7 100644 --- a/src/test/regress/expected/join.out +++ b/src/test/regress/expected/join.out @@ -5569,6 +5569,18 @@ select atts.relid::regclass, s.* from pg_stats s join ERROR: column atts.relid does not exist LINE 1: select atts.relid::regclass, s.* from pg_stats s join ^ +-- Test bug in rangetable flattening +explain (verbose, costs off) +select 1 from + (select * from int8_tbl where q1 <> (select 42) offset 0) ss +where false; + QUERY PLAN +-------------------------- + Result + Output: 1 + One-Time Filter: false +(3 rows) + -- -- Test LATERAL -- diff --git a/src/test/regress/sql/join.sql b/src/test/regress/sql/join.sql index 2ff68879d2287..2b2e09495505f 100644 --- a/src/test/regress/sql/join.sql +++ b/src/test/regress/sql/join.sql @@ -2086,6 +2086,12 @@ select atts.relid::regclass, s.* from pg_stats s join indexrelid from pg_index i) atts on atts.attnum = a.attnum where schemaname != 'pg_catalog'; +-- Test bug in rangetable flattening +explain (verbose, costs off) +select 1 from + (select * from int8_tbl where q1 <> (select 42) offset 0) ss +where false; + -- -- Test LATERAL --