sl@0: # 2001 September 15
sl@0: #
sl@0: # The author disclaims copyright to this source code.  In place of
sl@0: # a legal notice, here is a blessing:
sl@0: #
sl@0: #    May you do good and not evil.
sl@0: #    May you find forgiveness for yourself and forgive others.
sl@0: #    May you share freely, never taking more than you give.
sl@0: #
sl@0: #***********************************************************************
sl@0: # This file implements regression tests for SQLite library.  The
sl@0: # focus of this file is testing SELECT statements that are part of
sl@0: # expressions.
sl@0: #
sl@0: # $Id: subselect.test,v 1.16 2008/08/04 03:51:24 danielk1977 Exp $
sl@0: 
sl@0: set testdir [file dirname $argv0]
sl@0: source $testdir/tester.tcl
sl@0: 
sl@0: # Omit this whole file if the library is build without subquery support.
sl@0: ifcapable !subquery {
sl@0:   finish_test
sl@0:   return
sl@0: }
sl@0: 
sl@0: # Basic sanity checking.  Try a simple subselect.
sl@0: #
sl@0: do_test subselect-1.1 {
sl@0:   execsql {
sl@0:     CREATE TABLE t1(a int, b int);
sl@0:     INSERT INTO t1 VALUES(1,2);
sl@0:     INSERT INTO t1 VALUES(3,4);
sl@0:     INSERT INTO t1 VALUES(5,6);
sl@0:   }
sl@0:   execsql {SELECT * FROM t1 WHERE a = (SELECT count(*) FROM t1)}
sl@0: } {3 4}
sl@0: 
sl@0: # Try a select with more than one result column.
sl@0: #
sl@0: do_test subselect-1.2 {
sl@0:   set v [catch {execsql {SELECT * FROM t1 WHERE a = (SELECT * FROM t1)}} msg]
sl@0:   lappend v $msg
sl@0: } {1 {only a single result allowed for a SELECT that is part of an expression}}
sl@0: 
sl@0: # A subselect without an aggregate.
sl@0: #
sl@0: do_test subselect-1.3a {
sl@0:   execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=2)}
sl@0: } {2}
sl@0: do_test subselect-1.3b {
sl@0:   execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=4)}
sl@0: } {4}
sl@0: do_test subselect-1.3c {
sl@0:   execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=6)}
sl@0: } {6}
sl@0: do_test subselect-1.3d {
sl@0:   execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=8)}
sl@0: } {}
sl@0: ifcapable compound {
sl@0:   do_test subselect-1.3e {
sl@0:     execsql {
sl@0:       SELECT b FROM t1
sl@0:        WHERE a = (SELECT a FROM t1 UNION SELECT b FROM t1 ORDER BY 1);
sl@0:     }
sl@0:   } {2}
sl@0: }
sl@0: 
sl@0: # What if the subselect doesn't return any value.  We should get
sl@0: # NULL as the result.  Check it out.
sl@0: #
sl@0: do_test subselect-1.4 {
sl@0:   execsql {SELECT b from t1 where a = coalesce((SELECT a FROM t1 WHERE b=5),1)}
sl@0: } {2}
sl@0: 
sl@0: # Try multiple subselects within a single expression.
sl@0: #
sl@0: do_test subselect-1.5 {
sl@0:   execsql {
sl@0:     CREATE TABLE t2(x int, y int);
sl@0:     INSERT INTO t2 VALUES(1,2);
sl@0:     INSERT INTO t2 VALUES(2,4);
sl@0:     INSERT INTO t2 VALUES(3,8);
sl@0:     INSERT INTO t2 VALUES(4,16);
sl@0:   }
sl@0:   execsql {
sl@0:     SELECT y from t2 
sl@0:     WHERE x = (SELECT sum(b) FROM t1 where a notnull) - (SELECT sum(a) FROM t1)
sl@0:   }
sl@0: } {8}
sl@0: 
sl@0: # Try something useful.  Delete every entry from t2 where the
sl@0: # x value is less than half of the maximum.
sl@0: #
sl@0: do_test subselect-1.6 {
sl@0:   execsql {DELETE FROM t2 WHERE x < 0.5*(SELECT max(x) FROM t2)}
sl@0:   execsql {SELECT x FROM t2 ORDER BY x}
sl@0: } {2 3 4}
sl@0: 
sl@0: # Make sure sorting works for SELECTs there used as a scalar expression.
sl@0: #
sl@0: do_test subselect-2.1 {
sl@0:   execsql {
sl@0:     SELECT (SELECT a FROM t1 ORDER BY a), (SELECT a FROM t1 ORDER BY a DESC)
sl@0:   }
sl@0: } {1 5}
sl@0: do_test subselect-2.2 {
sl@0:   execsql {
sl@0:     SELECT 1 IN (SELECT a FROM t1 ORDER BY a);
sl@0:   }
sl@0: } {1}
sl@0: do_test subselect-2.3 {
sl@0:   execsql {
sl@0:     SELECT 2 IN (SELECT a FROM t1 ORDER BY a DESC);
sl@0:   }
sl@0: } {0}
sl@0: 
sl@0: # Verify that the ORDER BY clause is honored in a subquery.
sl@0: #
sl@0: ifcapable compound {
sl@0: do_test subselect-3.1 {
sl@0:   execsql {
sl@0:     CREATE TABLE t3(x int);
sl@0:     INSERT INTO t3 SELECT a FROM t1 UNION ALL SELECT b FROM t1;
sl@0:     SELECT * FROM t3 ORDER BY x;
sl@0:   }
sl@0: } {1 2 3 4 5 6}
sl@0: } ;# ifcapable compound
sl@0: ifcapable !compound {
sl@0: do_test subselect-3.1 {
sl@0:   execsql {
sl@0:     CREATE TABLE t3(x int);
sl@0:     INSERT INTO t3 SELECT a FROM t1; 
sl@0:     INSERT INTO t3 SELECT b FROM t1;
sl@0:     SELECT * FROM t3 ORDER BY x;
sl@0:   }
sl@0: } {1 2 3 4 5 6}
sl@0: } ;# ifcapable !compound
sl@0: 
sl@0: do_test subselect-3.2 {
sl@0:   execsql {
sl@0:     SELECT sum(x) FROM (SELECT x FROM t3 ORDER BY x LIMIT 2);
sl@0:   }
sl@0: } {3}
sl@0: do_test subselect-3.3 {
sl@0:   execsql {
sl@0:     SELECT sum(x) FROM (SELECT x FROM t3 ORDER BY x DESC LIMIT 2);
sl@0:   }
sl@0: } {11}
sl@0: do_test subselect-3.4 {
sl@0:   execsql {
sl@0:     SELECT (SELECT x FROM t3 ORDER BY x);
sl@0:   }
sl@0: } {1}
sl@0: do_test subselect-3.5 {
sl@0:   execsql {
sl@0:     SELECT (SELECT x FROM t3 ORDER BY x DESC);
sl@0:   }
sl@0: } {6}
sl@0: do_test subselect-3.6 {
sl@0:   execsql {
sl@0:     SELECT (SELECT x FROM t3 ORDER BY x LIMIT 1);
sl@0:   }
sl@0: } {1}
sl@0: do_test subselect-3.7 {
sl@0:   execsql {
sl@0:     SELECT (SELECT x FROM t3 ORDER BY x DESC LIMIT 1);
sl@0:   }
sl@0: } {6}
sl@0: do_test subselect-3.8 {
sl@0:   execsql {
sl@0:     SELECT (SELECT x FROM t3 ORDER BY x LIMIT 1 OFFSET 2);
sl@0:   }
sl@0: } {3}
sl@0: do_test subselect-3.9 {
sl@0:   execsql {
sl@0:     SELECT (SELECT x FROM t3 ORDER BY x DESC LIMIT 1 OFFSET 2);
sl@0:   }
sl@0: } {4}
sl@0: do_test subselect-3.10 {
sl@0:   execsql {
sl@0:     SELECT x FROM t3 WHERE x IN
sl@0:        (SELECT x FROM t3 ORDER BY x DESC LIMIT 1 OFFSET 2);
sl@0:   }
sl@0: } {4}
sl@0: 
sl@0: # Ticket #2295.
sl@0: # Make sure type affinities work correctly on subqueries with
sl@0: # an ORDER BY clause.
sl@0: #
sl@0: do_test subselect-4.1 {
sl@0:   execsql {
sl@0:     CREATE TABLE t4(a TEXT, b TEXT);
sl@0:     INSERT INTO t4 VALUES('a','1');
sl@0:     INSERT INTO t4 VALUES('b','2');
sl@0:     INSERT INTO t4 VALUES('c','3');
sl@0:     SELECT a FROM t4 WHERE b IN (SELECT b FROM t4 ORDER BY b);
sl@0:   }
sl@0: } {a b c}
sl@0: do_test subselect-4.2 {
sl@0:   execsql {
sl@0:     SELECT a FROM t4 WHERE b IN (SELECT b FROM t4 ORDER BY b LIMIT 1);
sl@0:   }
sl@0: } {a}
sl@0: do_test subselect-4.3 {
sl@0:   execsql {
sl@0:     SELECT a FROM t4 WHERE b IN (SELECT b FROM t4 ORDER BY b DESC LIMIT 1);
sl@0:   }
sl@0: } {c}
sl@0: 
sl@0: finish_test