From: Dean Rasheed Date: Sat, 29 Mar 2025 09:51:23 +0000 (+0000) Subject: Fix MERGE with DO NOTHING actions into a partitioned table. X-Git-Tag: REL_16_9~48 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8d4cd3b4a88713bb1083ebee9e6e81bd703f4c3b;p=thirdparty%2Fpostgresql.git Fix MERGE with DO NOTHING actions into a partitioned table. ExecInitPartitionInfo() duplicates much of the logic in ExecInitMerge(), except that it failed to handle DO NOTHING actions. This would cause an "unknown action in MERGE WHEN clause" error if a MERGE with any DO NOTHING actions attempted to insert into a partition not already initialised by ExecInitModifyTable(). Bug: #18871 Reported-by: Alexander Lakhin Author: Tender Wang Reviewed-by: Gurjeet Singh Discussion: https://postgr.es/m/18871-b44e3c96de3bd2e8%40postgresql.org Backpatch-through: 15 --- diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c index 6de40aacfa5..f56117bbae8 100644 --- a/src/backend/executor/execPartition.c +++ b/src/backend/executor/execPartition.c @@ -873,7 +873,7 @@ ExecInitPartitionInfo(ModifyTableState *mtstate, EState *estate, * reference and make copy for this relation, converting stuff that * references attribute numbers to match this relation's. * - * This duplicates much of the logic in ExecInitMerge(), so something + * This duplicates much of the logic in ExecInitMerge(), so if something * changes there, look here too. */ if (node && node->operation == CMD_MERGE) @@ -944,6 +944,8 @@ ExecInitPartitionInfo(ModifyTableState *mtstate, EState *estate, NULL); break; case CMD_DELETE: + case CMD_NOTHING: + /* Nothing to do */ break; default: diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index b4cd0278695..94d7117ad61 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -3443,7 +3443,7 @@ ExecInitMerge(ModifyTableState *mtstate, EState *estate) case CMD_NOTHING: break; default: - elog(ERROR, "unknown operation"); + elog(ERROR, "unknown action in MERGE WHEN clause"); break; } } diff --git a/src/test/regress/expected/merge.out b/src/test/regress/expected/merge.out index bc9a59803fc..5d1be9f6b24 100644 --- a/src/test/regress/expected/merge.out +++ b/src/test/regress/expected/merge.out @@ -1698,6 +1698,23 @@ SELECT * FROM pa_target ORDER BY tid; 14 | 140 | inserted by merge (14 rows) +ROLLBACK; +-- bug #18871: ExecInitPartitionInfo()'s handling of DO NOTHING actions +BEGIN; +TRUNCATE pa_target; +MERGE INTO pa_target t + USING (VALUES (10, 100)) AS s(sid, delta) + ON t.tid = s.sid + WHEN NOT MATCHED THEN + INSERT VALUES (1, 10, 'inserted by merge') + WHEN MATCHED THEN + DO NOTHING; +SELECT * FROM pa_target ORDER BY tid, val; + tid | balance | val +-----+---------+------------------- + 1 | 10 | inserted by merge +(1 row) + ROLLBACK; DROP TABLE pa_target CASCADE; -- The target table is partitioned in the same way, but this time by attaching diff --git a/src/test/regress/sql/merge.sql b/src/test/regress/sql/merge.sql index 2a220a248f1..4609241b2a5 100644 --- a/src/test/regress/sql/merge.sql +++ b/src/test/regress/sql/merge.sql @@ -1060,6 +1060,19 @@ SELECT merge_func(); SELECT * FROM pa_target ORDER BY tid; ROLLBACK; +-- bug #18871: ExecInitPartitionInfo()'s handling of DO NOTHING actions +BEGIN; +TRUNCATE pa_target; +MERGE INTO pa_target t + USING (VALUES (10, 100)) AS s(sid, delta) + ON t.tid = s.sid + WHEN NOT MATCHED THEN + INSERT VALUES (1, 10, 'inserted by merge') + WHEN MATCHED THEN + DO NOTHING; +SELECT * FROM pa_target ORDER BY tid, val; +ROLLBACK; + DROP TABLE pa_target CASCADE; -- The target table is partitioned in the same way, but this time by attaching