1 files changed, 71 insertions, 0 deletions
diff --git a/src/test/regress/sql/subselect.sql b/src/test/regress/sql/subselect.sql
new file mode 100644
index 00000000000..a227c048ac3
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+++ b/src/test/regress/sql/subselect.sql
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+--
+-- Subselects
+--
+
+SELECT 1 AS one WHERE 1 IN (SELECT 1);
+
+SELECT 1 AS zero WHERE 1 NOT IN (SELECT 1);
+
+SELECT 1 AS zero WHERE 1 IN (SELECT 2);
+
+-- Set up some simple test tables
+
+CREATE TABLE SUBSELECT_TBL (
+  f1 integer,
+  f2 integer,
+  f3 float
+);
+
+INSERT INTO SUBSELECT_TBL VALUES (1, 2, 3);
+INSERT INTO SUBSELECT_TBL VALUES (2, 3, 4);
+INSERT INTO SUBSELECT_TBL VALUES (3, 4, 5);
+INSERT INTO SUBSELECT_TBL VALUES (1, 1, 1);
+INSERT INTO SUBSELECT_TBL VALUES (2, 2, 2);
+INSERT INTO SUBSELECT_TBL VALUES (3, 3, 3);
+INSERT INTO SUBSELECT_TBL VALUES (6, 7, 8);
+INSERT INTO SUBSELECT_TBL VALUES (8, 9, NULL);
+
+SELECT '' AS eight, * FROM SUBSELECT_TBL;
+
+-- Uncorrelated subselects
+
+SELECT '' AS two, f1 AS "Constant Select" FROM SUBSELECT_TBL
+  WHERE f1 IN (SELECT 1);
+
+SELECT '' AS six, f1 AS "Uncorrelated Field" FROM SUBSELECT_TBL
+  WHERE f1 IN (SELECT f2 FROM SUBSELECT_TBL);
+
+SELECT '' AS six, f1 AS "Uncorrelated Field" FROM SUBSELECT_TBL
+  WHERE f1 IN (SELECT f2 FROM SUBSELECT_TBL WHERE
+    f2 IN (SELECT f1 FROM SUBSELECT_TBL));
+
+-- Correlated subselects
+
+SELECT '' AS six, f1 AS "Correlated Field", f3 AS "Second Field"
+  FROM SUBSELECT_TBL
+  WHERE f1 IN (SELECT f2 FROM SUBSELECT_TBL WHERE f2 = f1);
+
+SELECT '' AS six, f1 AS "Correlated Field", f3 AS "Second Field"
+  FROM SUBSELECT_TBL
+  WHERE f1 IN (SELECT f2 FROM SUBSELECT_TBL WHERE CAST(f2 AS float) = f3);
+
+SELECT '' AS six, f1 AS "Correlated Field", f3 AS "Second Field"
+  FROM SUBSELECT_TBL
+  WHERE f1 IN (SELECT f2 FROM SUBSELECT_TBL WHERE f2 = CAST(f3 AS integer));
+
+SELECT '' AS five, f1 AS "Correlated Field"
+  FROM SUBSELECT_TBL
+  WHERE (f1, f2) IN (SELECT f2, CAST(f3 AS int4) FROM SUBSELECT_TBL WHERE f3 IS NOT NULL);
+
+SELECT '' AS three, f1 AS "Correlated Field"
+  FROM SUBSELECT_TBL
+  WHERE (f1, f2) NOT IN (SELECT f2, CAST(f3 AS int4) FROM SUBSELECT_TBL WHERE f3 IS NOT NULL);
+
+--
+-- Use some existing tables in the regression test
+--
+
+SELECT '' AS eight, ss.f1 AS "Correlated Field", ss.f3 AS "Second Field"
+  FROM SUBSELECT_TBL ss
+  WHERE f1 NOT IN (SELECT f1 FROM INT4_TBL WHERE f1 != ss.f1);
+