From 25f9e78dd03ad1fd67d435bdfbdd563db3938375 Mon Sep 17 00:00:00 2001 From: Ante Kresic Date: Wed, 13 May 2026 10:47:02 +0200 Subject: [PATCH] Reject REPLICA IDENTITY USING INDEX on column with invalid NOT NULL ALTER TABLE ... REPLICA IDENTITY USING INDEX verified key columns by reading pg_attribute.attnotnull, but commit a379061a22a8 made attnotnull true also for unvalidated (NOT VALID) not-null constraints, which do not prove the column null-free. An index over such a column could thus be marked as replica identity even though the column might contain NULLs, causing apply-side divergence for UPDATE/DELETE on the nullable rows. Fix by additionally requiring convalidated for the underlying constraint, mirroring the fix d9ffc27291f applied to ATExecAddIdentity for the analogous identity-column case. --- src/backend/commands/tablecmds.c | 29 +++++++++++++++++++ .../regress/expected/replica_identity.out | 23 +++++++++++++++ src/test/regress/sql/replica_identity.sql | 16 ++++++++++ 3 files changed, 68 insertions(+) diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 88451c91448..9944df931ad 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -18853,6 +18853,35 @@ ATExecReplicaIdentity(Relation rel, ReplicaIdentityStmt *stmt, LOCKMODE lockmode errmsg("index \"%s\" cannot be used as replica identity because column \"%s\" is nullable", RelationGetRelationName(indexRel), NameStr(attr->attname)))); + + /* + * attnotnull is set even for invalid (NOT VALID) not-null + * constraints, which do not prove the column is null-free, so verify + * that the underlying constraint is validated. + */ + { + HeapTuple contup; + Form_pg_constraint conForm; + + contup = findNotNullConstraintAttnum(RelationGetRelid(rel), attno); + if (!HeapTupleIsValid(contup)) + elog(ERROR, "cache lookup failed for not-null constraint on column \"%s\" of relation \"%s\"", + NameStr(attr->attname), RelationGetRelationName(rel)); + + conForm = (Form_pg_constraint) GETSTRUCT(contup); + if (!conForm->convalidated) + ereport(ERROR, + errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE), + errmsg("index \"%s\" cannot be used as replica identity because column \"%s\" has an invalid not-null constraint", + RelationGetRelationName(indexRel), + NameStr(attr->attname)), + /*- translator: second %s is a constraint characteristic such as NOT VALID */ + errdetail("The constraint \"%s\" is marked %s.", + NameStr(conForm->conname), "NOT VALID"), + errhint("You might need to validate it using %s.", + "ALTER TABLE ... VALIDATE CONSTRAINT")); + heap_freetuple(contup); + } } /* This index is suitable for use as a replica identity. Mark it. */ diff --git a/src/test/regress/expected/replica_identity.out b/src/test/regress/expected/replica_identity.out index 336b04fa278..7be6ab0115e 100644 --- a/src/test/regress/expected/replica_identity.out +++ b/src/test/regress/expected/replica_identity.out @@ -292,10 +292,33 @@ ALTER TABLE test_replica_identity5 DROP CONSTRAINT test_replica_identity5_pkey; ERROR: constraint "test_replica_identity5_pkey" of relation "test_replica_identity5" does not exist ALTER TABLE test_replica_identity5 ALTER b DROP NOT NULL; ERROR: column "b" is in index used as replica identity +-- An invalid (NOT VALID) not-null constraint sets attnotnull but does not +-- prove the column null-free, so the index must not be accepted as replica +-- identity until the constraint is validated. +CREATE TABLE test_replica_identity6 (id int); +INSERT INTO test_replica_identity6 VALUES (1), (NULL); +ALTER TABLE test_replica_identity6 ADD CONSTRAINT id_nn NOT NULL id NOT VALID; +CREATE UNIQUE INDEX test_replica_identity6_idx ON test_replica_identity6 (id); +-- should fail +ALTER TABLE test_replica_identity6 REPLICA IDENTITY USING INDEX test_replica_identity6_idx; +ERROR: index "test_replica_identity6_idx" cannot be used as replica identity because column "id" has an invalid not-null constraint +DETAIL: The constraint "id_nn" is marked NOT VALID. +HINT: You might need to validate it using ALTER TABLE ... VALIDATE CONSTRAINT. +-- after removing offending row and validating, it should succeed +DELETE FROM test_replica_identity6 WHERE id IS NULL; +ALTER TABLE test_replica_identity6 VALIDATE CONSTRAINT id_nn; +ALTER TABLE test_replica_identity6 REPLICA IDENTITY USING INDEX test_replica_identity6_idx; +SELECT relreplident FROM pg_class WHERE oid = 'test_replica_identity6'::regclass; + relreplident +-------------- + i +(1 row) + DROP TABLE test_replica_identity; DROP TABLE test_replica_identity2; DROP TABLE test_replica_identity3; DROP TABLE test_replica_identity4; DROP TABLE test_replica_identity5; +DROP TABLE test_replica_identity6; DROP TABLE test_replica_identity_othertable; DROP TABLE test_replica_identity_t3; diff --git a/src/test/regress/sql/replica_identity.sql b/src/test/regress/sql/replica_identity.sql index 30daec05b71..b202b30ae2b 100644 --- a/src/test/regress/sql/replica_identity.sql +++ b/src/test/regress/sql/replica_identity.sql @@ -134,10 +134,26 @@ ALTER TABLE test_replica_identity5 ALTER b SET NOT NULL; ALTER TABLE test_replica_identity5 DROP CONSTRAINT test_replica_identity5_pkey; ALTER TABLE test_replica_identity5 ALTER b DROP NOT NULL; +-- An invalid (NOT VALID) not-null constraint sets attnotnull but does not +-- prove the column null-free, so the index must not be accepted as replica +-- identity until the constraint is validated. +CREATE TABLE test_replica_identity6 (id int); +INSERT INTO test_replica_identity6 VALUES (1), (NULL); +ALTER TABLE test_replica_identity6 ADD CONSTRAINT id_nn NOT NULL id NOT VALID; +CREATE UNIQUE INDEX test_replica_identity6_idx ON test_replica_identity6 (id); +-- should fail +ALTER TABLE test_replica_identity6 REPLICA IDENTITY USING INDEX test_replica_identity6_idx; +-- after removing offending row and validating, it should succeed +DELETE FROM test_replica_identity6 WHERE id IS NULL; +ALTER TABLE test_replica_identity6 VALIDATE CONSTRAINT id_nn; +ALTER TABLE test_replica_identity6 REPLICA IDENTITY USING INDEX test_replica_identity6_idx; +SELECT relreplident FROM pg_class WHERE oid = 'test_replica_identity6'::regclass; + DROP TABLE test_replica_identity; DROP TABLE test_replica_identity2; DROP TABLE test_replica_identity3; DROP TABLE test_replica_identity4; DROP TABLE test_replica_identity5; +DROP TABLE test_replica_identity6; DROP TABLE test_replica_identity_othertable; DROP TABLE test_replica_identity_t3; -- 2.53.0