3 # The author disclaims copyright to this source code. In place of
4 # a legal notice, here is a blessing:
6 # May you do good and not evil.
7 # May you find forgiveness for yourself and forgive others.
8 # May you share freely, never taking more than you give.
10 #***********************************************************************
11 # This file implements regression tests for SQLite library. The
12 # focus of this file is testing SELECT statements that are part of
15 # $Id: subselect.test,v 1.12 2005/01/21 03:12:16 danielk1977 Exp $
17 set testdir [file dirname $argv0]
18 source $testdir/tester.tcl
20 # Omit this whole file if the library is build without subquery support.
26 # Basic sanity checking. Try a simple subselect.
28 do_test subselect-1.1 {
30 CREATE TABLE t1(a int, b int);
31 INSERT INTO t1 VALUES(1,2);
32 INSERT INTO t1 VALUES(3,4);
33 INSERT INTO t1 VALUES(5,6);
35 execsql {SELECT * FROM t1 WHERE a = (SELECT count(*) FROM t1)}
38 # Try a select with more than one result column.
40 do_test subselect-1.2 {
41 set v [catch {execsql {SELECT * FROM t1 WHERE a = (SELECT * FROM t1)}} msg]
43 } {1 {only a single result allowed for a SELECT that is part of an expression}}
45 # A subselect without an aggregate.
47 do_test subselect-1.3a {
48 execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=2)}
50 do_test subselect-1.3b {
51 execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=4)}
53 do_test subselect-1.3c {
54 execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=6)}
56 do_test subselect-1.3c {
57 execsql {SELECT b from t1 where a = (SELECT a FROM t1 WHERE b=8)}
60 # What if the subselect doesn't return any value. We should get
61 # NULL as the result. Check it out.
63 do_test subselect-1.4 {
64 execsql {SELECT b from t1 where a = coalesce((SELECT a FROM t1 WHERE b=5),1)}
67 # Try multiple subselects within a single expression.
69 do_test subselect-1.5 {
71 CREATE TABLE t2(x int, y int);
72 INSERT INTO t2 VALUES(1,2);
73 INSERT INTO t2 VALUES(2,4);
74 INSERT INTO t2 VALUES(3,8);
75 INSERT INTO t2 VALUES(4,16);
79 WHERE x = (SELECT sum(b) FROM t1 where a notnull) - (SELECT sum(a) FROM t1)
83 # Try something useful. Delete every entry from t2 where the
84 # x value is less than half of the maximum.
86 do_test subselect-1.6 {
87 execsql {DELETE FROM t2 WHERE x < 0.5*(SELECT max(x) FROM t2)}
88 execsql {SELECT x FROM t2 ORDER BY x}
91 # Make sure sorting works for SELECTs there used as a scalar expression.
93 do_test subselect-2.1 {
95 SELECT (SELECT a FROM t1 ORDER BY a), (SELECT a FROM t1 ORDER BY a DESC)
98 do_test subselect-2.2 {
100 SELECT 1 IN (SELECT a FROM t1 ORDER BY a);
103 do_test subselect-2.3 {
105 SELECT 2 IN (SELECT a FROM t1 ORDER BY a DESC);
109 # Verify that the ORDER BY clause is honored in a subquery.
112 do_test subselect-3.1 {
114 CREATE TABLE t3(x int);
115 INSERT INTO t3 SELECT a FROM t1 UNION ALL SELECT b FROM t1;
116 SELECT * FROM t3 ORDER BY x;
119 } ;# ifcapable compound
120 ifcapable !compound {
121 do_test subselect-3.1 {
123 CREATE TABLE t3(x int);
124 INSERT INTO t3 SELECT a FROM t1;
125 INSERT INTO t3 SELECT b FROM t1;
126 SELECT * FROM t3 ORDER BY x;
129 } ;# ifcapable !compound
131 do_test subselect-3.2 {
133 SELECT sum(x) FROM (SELECT x FROM t3 ORDER BY x LIMIT 2);
136 do_test subselect-3.3 {
138 SELECT sum(x) FROM (SELECT x FROM t3 ORDER BY x DESC LIMIT 2);
141 do_test subselect-3.4 {
143 SELECT (SELECT x FROM t3 ORDER BY x);
146 do_test subselect-3.5 {
148 SELECT (SELECT x FROM t3 ORDER BY x DESC);
151 do_test subselect-3.6 {
153 SELECT (SELECT x FROM t3 ORDER BY x LIMIT 1);
156 do_test subselect-3.7 {
158 SELECT (SELECT x FROM t3 ORDER BY x DESC LIMIT 1);
161 do_test subselect-3.8 {
163 SELECT (SELECT x FROM t3 ORDER BY x LIMIT 1 OFFSET 2);
166 do_test subselect-3.9 {
168 SELECT (SELECT x FROM t3 ORDER BY x DESC LIMIT 1 OFFSET 2);
171 do_test subselect-3.10 {
173 SELECT x FROM t3 WHERE x IN
174 (SELECT x FROM t3 ORDER BY x DESC LIMIT 1 OFFSET 2);