From f8cfe07fd11e5caeddac93460e94cd72a23b1d2d Mon Sep 17 00:00:00 2001
From: Marco Slot <marco.slot@gmail.com>
Date: Wed, 2 May 2018 16:23:32 +0200
Subject: [PATCH] Support intermediate results in distributed INSERT..SELECT

---
 .../planner/insert_select_planner.c           |  2 +-
 .../regress/expected/multi_insert_select.out  | 19 +++++++++++++++++++
 src/test/regress/sql/multi_insert_select.sql  | 15 +++++++++++++++
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/src/backend/distributed/planner/insert_select_planner.c b/src/backend/distributed/planner/insert_select_planner.c
index de312022d..46fb12e47 100644
--- a/src/backend/distributed/planner/insert_select_planner.c
+++ b/src/backend/distributed/planner/insert_select_planner.c
@@ -332,7 +332,7 @@ DistributedInsertSelectSupported(Query *queryTree, RangeTblEntry *insertRte,
 		}
 	}
 
-	if (contain_volatile_functions((Node *) queryTree))
+	if (FindNodeCheck((Node *) queryTree, CitusIsVolatileFunction))
 	{
 		return DeferredError(ERRCODE_FEATURE_NOT_SUPPORTED,
 							 "volatile functions are not allowed in distributed "
diff --git a/src/test/regress/expected/multi_insert_select.out b/src/test/regress/expected/multi_insert_select.out
index eefbb88a9..6e86f6d51 100644
--- a/src/test/regress/expected/multi_insert_select.out
+++ b/src/test/regress/expected/multi_insert_select.out
@@ -1775,6 +1775,25 @@ SELECT count(*) FROM raw_events_second;
     38
 (1 row)
 
+-- intermediate results (CTEs) should be allowed when doing INSERT...SELECT within a CTE
+WITH series AS (
+  SELECT s AS val FROM generate_series(60,70) s
+),
+inserts AS (
+  INSERT INTO raw_events_second (user_id)
+  SELECT
+    user_id
+  FROM
+    raw_events_first JOIN series ON (value_1 = val)
+  RETURNING
+    NULL
+)
+SELECT count(*) FROM inserts;
+ count 
+-------
+     2
+(1 row)
+
 -- we need this in our next test
 truncate raw_events_first;
 SET client_min_messages TO DEBUG2;
diff --git a/src/test/regress/sql/multi_insert_select.sql b/src/test/regress/sql/multi_insert_select.sql
index 6d85c4230..2ac88a69f 100644
--- a/src/test/regress/sql/multi_insert_select.sql
+++ b/src/test/regress/sql/multi_insert_select.sql
@@ -1420,6 +1420,21 @@ INSERT INTO raw_events_first (user_id, time, value_1, value_2, value_3, value_4)
 INSERT INTO raw_events_second SELECT * FROM test_view WHERE user_id = 17 GROUP BY 1,2,3,4,5,6;
 SELECT count(*) FROM raw_events_second;
 
+-- intermediate results (CTEs) should be allowed when doing INSERT...SELECT within a CTE
+WITH series AS (
+  SELECT s AS val FROM generate_series(60,70) s
+),
+inserts AS (
+  INSERT INTO raw_events_second (user_id)
+  SELECT
+    user_id
+  FROM
+    raw_events_first JOIN series ON (value_1 = val)
+  RETURNING
+    NULL
+)
+SELECT count(*) FROM inserts;
+
 -- we need this in our next test
 truncate raw_events_first;