3 files changed, 35 insertions, 9 deletions

diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index b8b9d2a85f7..ff12e2e1364 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -1036,6 +1036,9 @@ InitPlan(QueryDesc *queryDesc, int eflags)
  * Generally the parser and/or planner should have noticed any such mistake
  * already, but let's make sure.
  *
+ * For INSERT ON CONFLICT, the result relation is required to support the
+ * onConflictAction, regardless of whether a conflict actually occurs.
+ *
  * For MERGE, mergeActions is the list of actions that may be performed.  The
  * result relation is required to support every action, regardless of whether
  * or not they are all executed.
@@ -1045,7 +1048,7 @@ InitPlan(QueryDesc *queryDesc, int eflags)
  */
 void
 CheckValidResultRel(ResultRelInfo *resultRelInfo, CmdType operation,
-					List *mergeActions)
+					OnConflictAction onConflictAction, List *mergeActions)
 {
 	Relation	resultRel = resultRelInfo->ri_RelationDesc;
 	FdwRoutine *fdwroutine;
@@ -1058,7 +1061,23 @@ CheckValidResultRel(ResultRelInfo *resultRelInfo, CmdType operation,
 	{
 		case RELKIND_RELATION:
 		case RELKIND_PARTITIONED_TABLE:
-			CheckCmdReplicaIdentity(resultRel, operation);
+
+			/*
+			 * For MERGE, check that the target relation supports each action.
+			 * For other operations, just check the operation itself.
+			 */
+			if (operation == CMD_MERGE)
+				foreach_node(MergeAction, action, mergeActions)
+					CheckCmdReplicaIdentity(resultRel, action->commandType);
+			else
+				CheckCmdReplicaIdentity(resultRel, operation);
+
+			/*
+			 * For INSERT ON CONFLICT DO UPDATE, additionally check that the
+			 * target relation supports UPDATE.
+			 */
+			if (onConflictAction == ONCONFLICT_UPDATE)
+				CheckCmdReplicaIdentity(resultRel, CMD_UPDATE);
 			break;
 		case RELKIND_SEQUENCE:
 			ereport(ERROR,
diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index 514eae1037d..1f2da072632 100644
--- a/src/backend/executor/execPartition.c
+++ b/src/backend/executor/execPartition.c
@@ -360,8 +360,12 @@ ExecFindPartition(ModifyTableState *mtstate,
 											   true, false);
 				if (rri)
 				{
+					ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
+
 					/* Verify this ResultRelInfo allows INSERTs */
-					CheckValidResultRel(rri, CMD_INSERT, NIL);
+					CheckValidResultRel(rri, CMD_INSERT,
+										node ? node->onConflictAction : ONCONFLICT_NONE,
+										NIL);
 
 					/*
 					 * Initialize information needed to insert this and
@@ -527,7 +531,8 @@ ExecInitPartitionInfo(ModifyTableState *mtstate, EState *estate,
 	 * partition-key becomes a DELETE+INSERT operation, so this check is still
 	 * required when the operation is CMD_UPDATE.
 	 */
-	CheckValidResultRel(leaf_part_rri, CMD_INSERT, NIL);
+	CheckValidResultRel(leaf_part_rri, CMD_INSERT,
+						node ? node->onConflictAction : ONCONFLICT_NONE, NIL);
 
 	/*
 	 * Open partition indices.  The user may have asked to check for conflicts
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 7c6c2c1f6e4..4c5647ac38a 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -3402,7 +3402,7 @@ lmerge_matched:
 							 * the tuple moved, and setting our current
 							 * resultRelInfo to that.
 							 */
-							if (ItemPointerIndicatesMovedPartitions(&context->tmfd.ctid))
+							if (ItemPointerIndicatesMovedPartitions(tupleid))
 								ereport(ERROR,
 										(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
 										 errmsg("tuple to be merged was already moved to another partition due to concurrent update")));
@@ -3450,12 +3450,13 @@ lmerge_matched:
 									if (ItemPointerIsValid(&lockedtid))
 										UnlockTuple(resultRelInfo->ri_RelationDesc, &lockedtid,
 													InplaceUpdateTupleLock);
-									LockTuple(resultRelInfo->ri_RelationDesc, &context->tmfd.ctid,
+									LockTuple(resultRelInfo->ri_RelationDesc, tupleid,
 											  InplaceUpdateTupleLock);
-									lockedtid = context->tmfd.ctid;
+									lockedtid = *tupleid;
 								}
+
 								if (!table_tuple_fetch_row_version(resultRelationDesc,
-																   &context->tmfd.ctid,
+																   tupleid,
 																   SnapshotAny,
 																   resultRelInfo->ri_oldTupleSlot))
 									elog(ERROR, "failed to fetch the target tuple");
@@ -4811,7 +4812,8 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
 		/*
 		 * Verify result relation is a valid target for the current operation
 		 */
-		CheckValidResultRel(resultRelInfo, operation, mergeActions);
+		CheckValidResultRel(resultRelInfo, operation, node->onConflictAction,
+							mergeActions);
 
 		resultRelInfo++;
 		i++;