2 files changed, 50 insertions, 0 deletions
diff --git a/src/test/regress/expected/merge.out b/src/test/regress/expected/merge.out
index 0e59bae1a7f..c236f155c08 100644
--- a/src/test/regress/expected/merge.out
+++ b/src/test/regress/expected/merge.out
@@ -2711,6 +2711,35 @@ SELECT * FROM tgt;
 (0 rows)
 
 DROP TABLE src, tgt;
+ 
+--
+-- test for bug #18634 (wrong varnullingrels error)
+--
+CREATE TABLE bug18634t (a int, b int, c text);
+INSERT INTO bug18634t VALUES(1, 10, 'tgt1'), (2, 20, 'tgt2');
+CREATE VIEW bug18634v AS
+  SELECT * FROM bug18634t WHERE EXISTS (SELECT 1 FROM bug18634t);
+CREATE TABLE bug18634s (a int, b int, c text);
+INSERT INTO bug18634s VALUES (1, 2, 'src1');
+MERGE INTO bug18634v t USING bug18634s s ON s.a = t.a
+  WHEN MATCHED THEN UPDATE SET b = s.b
+  WHEN NOT MATCHED BY SOURCE THEN DELETE
+  RETURNING merge_action(), s.c, t.*;
+ merge_action |  c   | a | b  |  c   
+--------------+------+---+----+------
+ UPDATE       | src1 | 1 |  2 | tgt1
+ DELETE       |      | 2 | 20 | tgt2
+(2 rows)
+
+SELECT * FROM bug18634t;
+ a | b |  c   
+---+---+------
+ 1 | 2 | tgt1
+(1 row)
+
+DROP TABLE bug18634t CASCADE;
+NOTICE:  drop cascades to view bug18634v
+DROP TABLE bug18634s;
 -- prepare
 RESET SESSION AUTHORIZATION;
 -- try a system catalog
diff --git a/src/test/regress/sql/merge.sql b/src/test/regress/sql/merge.sql
index 2a7753c65b0..ce9981d70b1 100644
--- a/src/test/regress/sql/merge.sql
+++ b/src/test/regress/sql/merge.sql
@@ -1727,6 +1727,27 @@ MERGE INTO tgt USING src ON tgt.a IS NOT DISTINCT FROM src.a
 SELECT * FROM tgt;
 
 DROP TABLE src, tgt;
+ 
+--
+-- test for bug #18634 (wrong varnullingrels error)
+--
+CREATE TABLE bug18634t (a int, b int, c text);
+INSERT INTO bug18634t VALUES(1, 10, 'tgt1'), (2, 20, 'tgt2');
+CREATE VIEW bug18634v AS
+  SELECT * FROM bug18634t WHERE EXISTS (SELECT 1 FROM bug18634t);
+
+CREATE TABLE bug18634s (a int, b int, c text);
+INSERT INTO bug18634s VALUES (1, 2, 'src1');
+
+MERGE INTO bug18634v t USING bug18634s s ON s.a = t.a
+  WHEN MATCHED THEN UPDATE SET b = s.b
+  WHEN NOT MATCHED BY SOURCE THEN DELETE
+  RETURNING merge_action(), s.c, t.*;
+
+SELECT * FROM bug18634t;
+
+DROP TABLE bug18634t CASCADE;
+DROP TABLE bug18634s;
 
 -- prepare