Fix replica identity check for a partitioned table.

Amit Kapila · Amit Kapila · commit 1df86aac517d · 2022-08-16T14:30:27.000+05:30
The current publisher code checks if UPDATE or DELETE can be executed with the replica identity of the table even if it's a partitioned table. We can skip checking the replica identity for partitioned tables because the operations are actually performed on the leaf partitions (not the partitioned table). Reported-by: Brad Nicholson Author: Hou Zhijie Reviewed-by: Peter Smith, Amit Kapila Backpatch-through: 13 Discussion: https://postgr.es/m/CAMMnM%3D8i5DohH%3DYKzV0_wYuYSYvuOJoL9F5nzXTc%2ByzsG1f6rg%40mail.gmail.com
diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c
@@ -565,6 +565,13 @@ CheckCmdReplicaIdentity(Relation rel, CmdType cmd)
 {
 	PublicationActions *pubactions;
 
+	/*
+	 * Skip checking the replica identity for partitioned tables, because the
+	 * operations are actually performed on the leaf partitions.
+	 */
+	if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
+		return;
+
 	/* We only need to do checks for UPDATE and DELETE. */
 	if (cmd != CMD_UPDATE && cmd != CMD_DELETE)
 		return;
diff --git a/src/test/regress/expected/publication.out b/src/test/regress/expected/publication.out
@@ -140,6 +140,8 @@ ALTER PUBLICATION testpub_forparted ADD TABLE testpub_parted;
 Tables:
     "public.testpub_parted"
 
+-- works despite missing REPLICA IDENTITY, because no actual update happened
+UPDATE testpub_parted SET a = 1 WHERE false;
 -- should now fail, because parent's publication replicates updates
 UPDATE testpub_parted1 SET a = 1;
 ERROR:  cannot update table "testpub_parted1" because it does not have a replica identity and publishes updates
diff --git a/src/test/regress/sql/publication.sql b/src/test/regress/sql/publication.sql
@@ -85,6 +85,8 @@ UPDATE testpub_parted1 SET a = 1;
 -- only parent is listed as being in publication, not the partition
 ALTER PUBLICATION testpub_forparted ADD TABLE testpub_parted;
 \dRp+ testpub_forparted
+-- works despite missing REPLICA IDENTITY, because no actual update happened
+UPDATE testpub_parted SET a = 1 WHERE false;
 -- should now fail, because parent's publication replicates updates
 UPDATE testpub_parted1 SET a = 1;
 ALTER TABLE testpub_parted DETACH PARTITION testpub_parted1;
