2 files changed, 20 insertions, 13 deletions

diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index b2ee92eb155..954a96c6966 100644
--- a/src/backend/executor/execPartition.c
+++ b/src/backend/executor/execPartition.c
@@ -333,6 +333,13 @@ ExecInitPartitionInfo(ModifyTableState *mtstate,
 					  estate->es_instrument);
 
 	/*
+	 * Verify result relation is a valid target for an INSERT.  An UPDATE of a
+	 * 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);
+
+	/*
 	 * Since we've just initialized this ResultRelInfo, it's not in any list
 	 * attached to the estate as yet.  Add it, so that it can be found later.
 	 *
@@ -344,9 +351,6 @@ ExecInitPartitionInfo(ModifyTableState *mtstate,
 		lappend(estate->es_tuple_routing_result_relations,
 				leaf_part_rri);
 
-	/* Set up information needed for routing tuples to this partition. */
-	ExecInitRoutingInfo(mtstate, estate, proute, leaf_part_rri, partidx);
-
 	/*
 	 * Open partition indices.  The user may have asked to check for conflicts
 	 * within this leaf partition and do "nothing" instead of throwing an
@@ -489,6 +493,9 @@ ExecInitPartitionInfo(ModifyTableState *mtstate,
 									&mtstate->ps, RelationGetDescr(partrel));
 	}
 
+	/* Set up information needed for routing tuples to the partition. */
+	ExecInitRoutingInfo(mtstate, estate, proute, leaf_part_rri, partidx);
+
 	/*
 	 * If there is an ON CONFLICT clause, initialize state for it.
 	 */
@@ -655,8 +662,7 @@ ExecInitPartitionInfo(ModifyTableState *mtstate,
 
 /*
  * ExecInitRoutingInfo
- *		Set up information needed for routing tuples to a leaf partition if
- *		routable; else abort the operation
+ *		Set up information needed for routing tuples to a leaf partition
  */
 void
 ExecInitRoutingInfo(ModifyTableState *mtstate,
@@ -667,9 +673,6 @@ ExecInitRoutingInfo(ModifyTableState *mtstate,
 {
 	MemoryContext oldContext;
 
-	/* Verify the partition is a valid target for INSERT */
-	CheckValidResultRel(partRelInfo, CMD_INSERT);
-
 	/*
 	 * Switch into per-query memory context.
 	 */
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index f6482f8411b..71314e73bcf 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1700,20 +1700,24 @@ ExecPrepareTupleRouting(ModifyTableState *mtstate,
 										partidx);
 
 	/*
-	 * Set up information needed for routing tuples to the partition if we
-	 * didn't yet (ExecInitRoutingInfo would abort the operation if the
-	 * partition isn't routable).
+	 * Check whether the partition is routable if we didn't yet
 	 *
 	 * Note: an UPDATE of a partition key invokes an INSERT that moves the
-	 * tuple to a new partition.  This setup would be needed for a subplan
+	 * tuple to a new partition.  This check would be applied to a subplan
 	 * partition of such an UPDATE that is chosen as the partition to route
-	 * the tuple to.  The reason we do this setup here rather than in
+	 * the tuple to.  The reason we do this check here rather than in
 	 * ExecSetupPartitionTupleRouting is to avoid aborting such an UPDATE
 	 * unnecessarily due to non-routable subplan partitions that may not be
 	 * chosen for update tuple movement after all.
 	 */
 	if (!partrel->ri_PartitionReadyForRouting)
+	{
+		/* Verify the partition is a valid target for INSERT. */
+		CheckValidResultRel(partrel, CMD_INSERT);
+
+		/* Set up information needed for routing tuples to the partition. */
 		ExecInitRoutingInfo(mtstate, estate, proute, partrel, partidx);
+	}
 
 	/*
 	 * Make it look like we are inserting into the partition.