The following script: CREATE TABLE pt(a int, b int) PARTITION BY LIST(a); CREATE TABLE p1 PARTITION OF pt FOR VALUES IN (a);
MERGE INTO pt USING (SELECT 2 AS a) AS q ON pt.a = q.a WHEN NOT MATCHED THEN INSERT VALUES (1, 2) WHEN MATCHED THEN DO NOTHING; fails with: ERROR: XX000: unknown action in MERGE WHEN clause LOCATION: ExecInitPartitionInfo, execPartition.c:962
This error is triggered on REL_15_STABLE (starting from bf5c4b3d9) .. master. Before bf5c4b3d9, the MERGE produced ERROR: variable not found in subplan target lists.
This anomaly is discovered with SQLsmith.
I tried a quick fix by adding "case CMD_NOTHING" after "case CMD_DELETE" like below:
case CMD_DELETE:
case CMD_NOTHING:
break;
It can work, and all regression tests pass. But I don't look into more details. This solution may not fix the root cause.
