Avoid ERROR at ON COMMIT DELETE ROWS after relhassubclass=f.

nmisch · nmisch · commit d34b671a63e6 · 2025-04-20T08:28:53.000-07:00
Commit 7102070 fixed a similar bug, but it missed the case of database-wide ANALYZE ("use_own_xacts" mode). Commit a07e03f changed consequences from silent discard of a pg_class stats (relpages et al.) update to ERROR "tuple to be updated was already modified". Losing a relpages update of an ON COMMIT DELETE ROWS table was negligible, but a COMMIT-time error isn't negligible. Back-patch to v13 (all supported versions). Reported-by: Richard Guo <guofenglinux@gmail.com Reported-by: Robins Tharakan <tharakan@gmail.com> Discussion: https://postgr.es/m/CAMbWs4-XwMKMKJ_GT=p3_-_=j9rQSEs1FbDFUnW9zHuKPsPNEQ@mail.gmail.com Backpatch-through: 13
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
@@ -470,6 +470,8 @@ vacuum(List *relations, VacuumParams *params,
 				if (use_own_xacts)
 				{
 					PopActiveSnapshot();
+					/* standard_ProcessUtility() does CCI if !use_own_xacts */
+					CommandCounterIncrement();
 					CommitTransactionCommand();
 				}
 				else
diff --git a/src/test/regress/expected/maintain_every.out b/src/test/regress/expected/maintain_every.out
@@ -0,0 +1,33 @@
+-- Test maintenance commands that visit every eligible relation.  Run as a
+-- non-superuser, to skip other users' tables.
+CREATE ROLE regress_maintain;
+SET ROLE regress_maintain;
+-- Test database-wide ANALYZE ("use_own_xacts" mode) setting relhassubclass=f
+-- for non-partitioning inheritance, w/ ON COMMIT DELETE ROWS building an
+-- empty index.
+CREATE TEMP TABLE past_inh_db_other (); -- need 2 tables for "use_own_xacts"
+CREATE TEMP TABLE past_inh_db_parent () ON COMMIT DELETE ROWS;
+CREATE TEMP TABLE past_inh_db_child () INHERITS (past_inh_db_parent);
+CREATE INDEX ON past_inh_db_parent ((1));
+ANALYZE past_inh_db_parent;
+SELECT reltuples, relhassubclass
+  FROM pg_class WHERE oid = 'past_inh_db_parent'::regclass;
+ reltuples | relhassubclass 
+-----------+----------------
+         0 | t
+(1 row)
+
+DROP TABLE past_inh_db_child;
+SET client_min_messages = error; -- hide WARNINGs for other users' tables
+ANALYZE;
+RESET client_min_messages;
+SELECT reltuples, relhassubclass
+  FROM pg_class WHERE oid = 'past_inh_db_parent'::regclass;
+ reltuples | relhassubclass 
+-----------+----------------
+         0 | f
+(1 row)
+
+DROP TABLE past_inh_db_parent, past_inh_db_other;
+RESET ROLE;
+DROP ROLE regress_maintain;
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
@@ -89,6 +89,10 @@ test: rules psql psql_crosstab amutils stats_ext collate.linux.utf8
 test: select_parallel
 test: write_parallel
 
+# Run this alone, because concurrent DROP TABLE would make non-superuser
+# "ANALYZE;" fail with "relation with OID $n does not exist".
+test: maintain_every
+
 # no relation related tests can be put in this group
 test: publication subscription
 
diff --git a/src/test/regress/sql/maintain_every.sql b/src/test/regress/sql/maintain_every.sql
@@ -0,0 +1,26 @@
+-- Test maintenance commands that visit every eligible relation.  Run as a
+-- non-superuser, to skip other users' tables.
+
+CREATE ROLE regress_maintain;
+SET ROLE regress_maintain;
+
+-- Test database-wide ANALYZE ("use_own_xacts" mode) setting relhassubclass=f
+-- for non-partitioning inheritance, w/ ON COMMIT DELETE ROWS building an
+-- empty index.
+CREATE TEMP TABLE past_inh_db_other (); -- need 2 tables for "use_own_xacts"
+CREATE TEMP TABLE past_inh_db_parent () ON COMMIT DELETE ROWS;
+CREATE TEMP TABLE past_inh_db_child () INHERITS (past_inh_db_parent);
+CREATE INDEX ON past_inh_db_parent ((1));
+ANALYZE past_inh_db_parent;
+SELECT reltuples, relhassubclass
+  FROM pg_class WHERE oid = 'past_inh_db_parent'::regclass;
+DROP TABLE past_inh_db_child;
+SET client_min_messages = error; -- hide WARNINGs for other users' tables
+ANALYZE;
+RESET client_min_messages;
+SELECT reltuples, relhassubclass
+  FROM pg_class WHERE oid = 'past_inh_db_parent'::regclass;
+DROP TABLE past_inh_db_parent, past_inh_db_other;
+
+RESET ROLE;
+DROP ROLE regress_maintain;

Original file line number	Diff line number	Diff line change
`@@ -470,6 +470,8 @@ vacuum(List relations, VacuumParams params,`
`470`	`470`	`if (use_own_xacts)`
`471`	`471`	`{`
`472`	`472`	`PopActiveSnapshot();`
	`473`	`+ /* standard_ProcessUtility() does CCI if !use_own_xacts */`
	`474`	`+ CommandCounterIncrement();`
`473`	`475`	`CommitTransactionCommand();`
`474`	`476`	`}`
`475`	`477`	`else`