Merge pull request #1600 from citusdata/fix_multi_row_returning

Add alias for target in multi-row INSERTs

src/backend/distributed/planner/deparse_shard_query.c

@@ -82,11 +82,15 @@ RebuildQueryStrings(Query *originalQuery, List *taskList)
 
 			UpdateRelationToShardNames((Node *) copiedSubquery, relationShardList);
 		}
-		else if (task->upsertQuery)
+		else if (task->upsertQuery || valuesRTE != NULL)
 		{
 			RangeTblEntry *rangeTableEntry = NULL;
 
-			/* setting an alias simplifies deparsing of UPSERTs */
+			/*
+			 * Always an alias in UPSERTs and multi-row INSERTs to avoid
+			 * deparsing issues (e.g. RETURNING might reference the original
+			 * table name, which has been replaced by a shard name).
+			 */
 			rangeTableEntry = linitial(query->rtable);
 			if (rangeTableEntry->alias == NULL)
 			{

src/test/regress/expected/multi_explain.out

@@ -305,7 +305,7 @@ Custom Scan (Citus Router)
   Tasks Shown: All
   ->  Task
         Node: host=localhost port=57638 dbname=regression
-        ->  Insert on lineitem_290000
+        ->  Insert on lineitem_290000 citus_table_alias
               ->  Values Scan on "*VALUES*"
 -- Test update
 EXPLAIN (COSTS FALSE)

src/test/regress/expected/multi_explain_0.out

@@ -305,7 +305,7 @@ Custom Scan (Citus Router)
   Tasks Shown: All
   ->  Task
         Node: host=localhost port=57638 dbname=regression
-        ->  Insert on lineitem_290000
+        ->  Insert on lineitem_290000 citus_table_alias
               ->  Values Scan on "*VALUES*"
 -- Test update
 EXPLAIN (COSTS FALSE)

src/test/regress/expected/multi_modifications.out

@@ -211,10 +211,18 @@ SELECT COUNT(*) FROM limit_orders WHERE id BETWEEN 12037 AND 12039;
      3
 (1 row)
 
--- even those with functions
+-- even those with functions and returning
 INSERT INTO limit_orders VALUES (22037, 'GOOG', 5634, now(), 'buy', 0.50),
                                 (22038, 'GOOG', 5634, now(), 'buy', 2.50),
-                                (22039, 'GOOG', 5634, now(), 'buy', 1.50);
+                                (22039, 'GOOG', 5634, now(), 'buy', 1.50)
+RETURNING id;
+  id   
+-------
+ 22038
+ 22039
+ 22037
+(3 rows)
+
 SELECT COUNT(*) FROM limit_orders WHERE id BETWEEN 22037 AND 22039;
  count 
 -------

src/test/regress/sql/multi_modifications.sql

@@ -153,10 +153,11 @@ INSERT INTO limit_orders VALUES (12037, 'GOOG', 5634, '2001-04-16 03:37:28', 'bu
 
 SELECT COUNT(*) FROM limit_orders WHERE id BETWEEN 12037 AND 12039;
 
--- even those with functions
+-- even those with functions and returning
 INSERT INTO limit_orders VALUES (22037, 'GOOG', 5634, now(), 'buy', 0.50),
                                 (22038, 'GOOG', 5634, now(), 'buy', 2.50),
-                                (22039, 'GOOG', 5634, now(), 'buy', 1.50);
+                                (22039, 'GOOG', 5634, now(), 'buy', 1.50)
+RETURNING id;
 
 SELECT COUNT(*) FROM limit_orders WHERE id BETWEEN 22037 AND 22039;