From 01c544e1afb99bc2a76803870010b7cd2907f3b5 Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Thu, 9 Jul 2026 10:10:07 +0200 Subject: [PATCH] Prohibit locking clauses on GRAPH_TABLE Specifying a locking clause (FOR UPDATE/SHARE) that names a GRAPH_TABLE alias currently results in an unhelpful "unrecognized RTE type: 8" error. This commit explicitly prohibits specifying a locking clause on a GRAPH_TABLE alias, raising a more user-friendly error instead. (Locking clause support for GRAPH_TABLE could be added as a separate feature in the future.) Author: SATYANARAYANA NARLAPURAM Author: Ayush Tiwari Reviewed-by: Ashutosh Bapat Discussion: https://www.postgresql.org/message-id/flat/CAHg%2BQDcE9wp6nOEC3SCRQ90nrCO%3DQF%2BOZq1MG8Qc6hnusmogqw%40mail.gmail.com --- src/backend/parser/analyze.c | 9 +++++++++ src/test/regress/expected/graph_table.out | 13 +++++++++++++ src/test/regress/sql/graph_table.sql | 4 ++++ 3 files changed, 26 insertions(+) diff --git a/src/backend/parser/analyze.c b/src/backend/parser/analyze.c index 739ea13d5db..ea97d236ea8 100644 --- a/src/backend/parser/analyze.c +++ b/src/backend/parser/analyze.c @@ -4002,6 +4002,15 @@ transformLockingClause(ParseState *pstate, Query *qry, LockingClause *lc, LCS_asString(lc->strength)), parser_errposition(pstate, thisrel->location))); break; + case RTE_GRAPH_TABLE: + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + /*------ + translator: %s is a SQL row locking clause such as FOR UPDATE */ + errmsg("%s cannot be applied to GRAPH_TABLE", + LCS_asString(lc->strength)), + parser_errposition(pstate, thisrel->location))); + break; /* Shouldn't be possible to see RTE_RESULT here */ diff --git a/src/test/regress/expected/graph_table.out b/src/test/regress/expected/graph_table.out index a3d78a7ac43..46566b2e32f 100644 --- a/src/test/regress/expected/graph_table.out +++ b/src/test/regress/expected/graph_table.out @@ -1106,4 +1106,17 @@ SELECT src.vname, count(*) FROM v1 AS src v13 | 1 (3 rows) +-- Locking clause on GRAPH_TABLE +SELECT * FROM GRAPH_TABLE (g1 MATCH (src IS vl1) COLUMNS (src.vname)) gt FOR UPDATE OF gt; -- not supported +ERROR: FOR UPDATE cannot be applied to GRAPH_TABLE +LINE 1: ...MATCH (src IS vl1) COLUMNS (src.vname)) gt FOR UPDATE OF gt; + ^ +SELECT * FROM GRAPH_TABLE (g1 MATCH (src IS vl1) COLUMNS (src.vname)) gt FOR UPDATE; -- ignored + vname +------- + v11 + v12 + v13 +(3 rows) + -- leave the objects behind for pg_upgrade/pg_dump tests diff --git a/src/test/regress/sql/graph_table.sql b/src/test/regress/sql/graph_table.sql index 6aacc2d4aa5..3fb0e50ddb2 100644 --- a/src/test/regress/sql/graph_table.sql +++ b/src/test/regress/sql/graph_table.sql @@ -619,4 +619,8 @@ SELECT src.vname, count(*) FROM v1 AS src HAVING count(*) >= (SELECT count(*) FROM GRAPH_TABLE (g1 MATCH (a IS vl1 | vl2) COLUMNS (a.vname AS n)) WHERE n = src.vname) ORDER BY vname; +-- Locking clause on GRAPH_TABLE +SELECT * FROM GRAPH_TABLE (g1 MATCH (src IS vl1) COLUMNS (src.vname)) gt FOR UPDATE OF gt; -- not supported +SELECT * FROM GRAPH_TABLE (g1 MATCH (src IS vl1) COLUMNS (src.vname)) gt FOR UPDATE; -- ignored + -- leave the objects behind for pg_upgrade/pg_dump tests