When modifying a foreign table, initialize tableoid field properly.

Failure to do this can cause AFTER ROW triggers or RETURNING expressions
that reference this field to misbehave.

Etsuro Fujita, reviewed by Thom Brown

src/backend/executor/nodeModifyTable.c

@@ -308,6 +308,12 @@ ExecInsert(ModifyTableState *mtstate,
 		/* FDW might have changed tuple */
 		tuple = ExecMaterializeSlot(slot);
 
+		/*
+		 * AFTER ROW Triggers or RETURNING expressions might reference the
+		 * tableoid column, so initialize t_tableOid before evaluating them.
+		 */
+		tuple->t_tableOid = RelationGetRelid(resultRelationDesc);
+
 		newId = InvalidOid;
 	}
 	else
@@ -561,6 +567,8 @@ ExecDelete(ItemPointer tupleid,
 	}
 	else if (resultRelInfo->ri_FdwRoutine)
 	{
+		HeapTuple	tuple;
+
 		/*
 		 * delete from foreign table: let the FDW do it
 		 *
@@ -579,6 +587,15 @@ ExecDelete(ItemPointer tupleid,
 
 		if (slot == NULL)		/* "do nothing" */
 			return NULL;
+
+		/*
+		 * RETURNING expressions might reference the tableoid column, so
+		 * initialize t_tableOid before evaluating them.
+		 */
+		if (slot->tts_isempty)
+			ExecStoreAllNullTuple(slot);
+		tuple = ExecMaterializeSlot(slot);
+		tuple->t_tableOid = RelationGetRelid(resultRelationDesc);
 	}
 	else
 	{
@@ -838,6 +855,12 @@ ExecUpdate(ItemPointer tupleid,
 
 		/* FDW might have changed tuple */
 		tuple = ExecMaterializeSlot(slot);
+
+		/*
+		 * AFTER ROW Triggers or RETURNING expressions might reference the
+		 * tableoid column, so initialize t_tableOid before evaluating them.
+		 */
+		tuple->t_tableOid = RelationGetRelid(resultRelationDesc);
 	}
 	else
 	{