From 452f38f84fb61b08e200c7bd0d96663701df299c Mon Sep 17 00:00:00 2001 From: jian he Date: Sat, 27 Sep 2025 17:46:45 +0800 Subject: [PATCH v1 1/1] ALTER TABLE each relation call ATPostAlterTypeCleanup only once bug demo: drop table if exists gtest25; CREATE TABLE gtest25 (a0 int, a int, b int GENERATED ALWAYS AS (a * 2 + a0) STORED); alter table gtest25 add constraint cc check (b > 0); alter table gtest25 alter column b set data type int8, ALTER COLUMN b SET EXPRESSION AS (a * 3 + a0); ERROR: cache lookup failed for constraint 18432 The reason it can only call once is: ATPostAlterTypeCleanup searches the system catalog for recreate objects such as STATISTICS, CONSTRAINTS. After that, the original object will be dropped via performMultipleDeletions. If ATPostAlterTypeCleanup is called a second time, the catalog cache lookup will fail because those objects were already removed during the first call. discussion: https://postgr.es/m/ --- src/backend/commands/tablecmds.c | 9 ++++++++- src/test/regress/expected/generated_stored.out | 2 ++ src/test/regress/expected/generated_virtual.out | 2 ++ src/test/regress/sql/generated_stored.sql | 2 ++ src/test/regress/sql/generated_virtual.sql | 2 ++ 5 files changed, 16 insertions(+), 1 deletion(-) diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 3be2e051d32..39b32af4b7e 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -5296,6 +5296,7 @@ ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode, AlterTableUtilityContext *context) { ListCell *ltab; + List *relids = NIL; /* * We process all the tables "in parallel", one pass at a time. This is @@ -5334,7 +5335,13 @@ ATRewriteCatalogs(List **wqueue, LOCKMODE lockmode, * done only once if multiple columns of a table are altered). */ if (pass == AT_PASS_ALTER_TYPE || pass == AT_PASS_SET_EXPRESSION) - ATPostAlterTypeCleanup(wqueue, tab, lockmode); + { + if (!list_member_oid(relids, tab->relid)) + { + ATPostAlterTypeCleanup(wqueue, tab, lockmode); + relids = lappend_oid(relids, tab->relid); + } + } if (tab->rel) { diff --git a/src/test/regress/expected/generated_stored.out b/src/test/regress/expected/generated_stored.out index adac2cedfb2..b0bc33576ca 100644 --- a/src/test/regress/expected/generated_stored.out +++ b/src/test/regress/expected/generated_stored.out @@ -1120,6 +1120,8 @@ SELECT * FROM gtest25 ORDER BY a; Indexes: "gtest25_pkey" PRIMARY KEY, btree (a) +ALTER TABLE gtest25 ADD CONSTRAINT cc CHECK(b > 9) NOT VALID; +ALTER TABLE gtest25 ALTER COLUMN b SET DATA TYPE INT8, ALTER COLUMN b SET EXPRESSION AS (a * 3); --ok -- ALTER TABLE ... ALTER COLUMN CREATE TABLE gtest27 ( a int, diff --git a/src/test/regress/expected/generated_virtual.out b/src/test/regress/expected/generated_virtual.out index d8645192351..1417369213c 100644 --- a/src/test/regress/expected/generated_virtual.out +++ b/src/test/regress/expected/generated_virtual.out @@ -1082,6 +1082,8 @@ SELECT * FROM gtest25 ORDER BY a; Indexes: "gtest25_pkey" PRIMARY KEY, btree (a) +ALTER TABLE gtest25 ADD CONSTRAINT cc CHECK(b > 9) NOT VALID; +ALTER TABLE gtest25 ALTER COLUMN b SET DATA TYPE INT8, ALTER COLUMN b SET EXPRESSION AS (a * 3); --ok -- ALTER TABLE ... ALTER COLUMN CREATE TABLE gtest27 ( a int, diff --git a/src/test/regress/sql/generated_stored.sql b/src/test/regress/sql/generated_stored.sql index f56fde8d4e5..e0c9ac32158 100644 --- a/src/test/regress/sql/generated_stored.sql +++ b/src/test/regress/sql/generated_stored.sql @@ -516,6 +516,8 @@ ALTER TABLE gtest25 ALTER COLUMN d SET DATA TYPE float8, ADD COLUMN y float8 GENERATED ALWAYS AS (d * 4) STORED; SELECT * FROM gtest25 ORDER BY a; \d gtest25 +ALTER TABLE gtest25 ADD CONSTRAINT cc CHECK(b > 9) NOT VALID; +ALTER TABLE gtest25 ALTER COLUMN b SET DATA TYPE INT8, ALTER COLUMN b SET EXPRESSION AS (a * 3); --ok -- ALTER TABLE ... ALTER COLUMN CREATE TABLE gtest27 ( diff --git a/src/test/regress/sql/generated_virtual.sql b/src/test/regress/sql/generated_virtual.sql index adfe88d74ae..b5d785734f4 100644 --- a/src/test/regress/sql/generated_virtual.sql +++ b/src/test/regress/sql/generated_virtual.sql @@ -559,6 +559,8 @@ ALTER TABLE gtest25 ALTER COLUMN d SET DATA TYPE float8, ADD COLUMN y float8 GENERATED ALWAYS AS (d * 4) VIRTUAL; SELECT * FROM gtest25 ORDER BY a; \d gtest25 +ALTER TABLE gtest25 ADD CONSTRAINT cc CHECK(b > 9) NOT VALID; +ALTER TABLE gtest25 ALTER COLUMN b SET DATA TYPE INT8, ALTER COLUMN b SET EXPRESSION AS (a * 3); --ok -- ALTER TABLE ... ALTER COLUMN CREATE TABLE gtest27 ( -- 2.34.1