sqlite/test/tkt3824.test
drh 46619d6787 Make sure that the optimizer realizes that an "x IS NULL" contraint does not
necessarily give a single-row result even on a UNIQUE index.  Ticket #3824. (CVS 6545)

FossilOrigin-Name: 207335fdbf992a2f5bc5982b3163a38016ba1b21
2009-04-24 14:51:42 +00:00

89 lines
2.2 KiB
Plaintext

# 2009 April 24
#
# The author disclaims copyright to this source code. In place of
# a legal notice, here is a blessing:
#
# May you do good and not evil.
# May you find forgiveness for yourself and forgive others.
# May you share freely, never taking more than you give.
#
#***********************************************************************
#
# Ticket #3824
#
# When you use an "IS NULL" constraint on a UNIQUE index, the result
# is not necessarily UNIQUE. Make sure the optimizer does not assume
# uniqueness.
#
# $Id: tkt3824.test,v 1.1 2009/04/24 14:51:42 drh Exp $
set testdir [file dirname $argv0]
source $testdir/tester.tcl
proc execsql_status {sql {db db}} {
set result [uplevel $db eval [list $sql]]
if {[db status sort]} {
concat $result sort
} else {
concat $result nosort
}
}
do_test tkt3824-1.1 {
db eval {
CREATE TABLE t1(a,b);
INSERT INTO t1 VALUES(1,NULL);
INSERT INTO t1 VALUES(9,NULL);
INSERT INTO t1 VALUES(5,NULL);
INSERT INTO t1 VALUES(123,NULL);
INSERT INTO t1 VALUES(-10,NULL);
CREATE UNIQUE INDEX t1b ON t1(b);
}
execsql_status {
SELECT a FROM t1 WHERE b IS NULL ORDER BY a;
}
} {-10 1 5 9 123 sort}
do_test tkt3824-1.2 {
execsql_status {
SELECT a FROM t1 WHERE b IS NULL ORDER BY b, a;
}
} {-10 1 5 9 123 sort}
do_test tkt3824-2.1 {
db eval {
CREATE TABLE t2(a,b,c);
INSERT INTO t2 VALUES(1,1,NULL);
INSERT INTO t2 VALUES(9,2,NULL);
INSERT INTO t2 VALUES(5,2,NULL);
INSERT INTO t2 VALUES(123,3,NULL);
INSERT INTO t2 VALUES(-10,3,NULL);
CREATE UNIQUE INDEX t2bc ON t2(b,c);
}
execsql_status {
SELECT a FROM t2 WHERE b=2 AND c IS NULL ORDER BY a;
}
} {5 9 sort}
do_test tkt3824-2.2 {
execsql_status {
SELECT a FROM t2 WHERE b=2 AND c IS NULL ORDER BY b, a;
}
} {5 9 sort}
do_test tkt3824-2.3 {
lsort [execsql_status {
SELECT a FROM t2 WHERE b=2 AND c IS NULL ORDER BY b;
}]
} {5 9 sort}
do_test tkt3824-3.1 {
db eval {
CREATE TABLE t3(x,y);
INSERT INTO t3 SELECT a, b FROM t1;
INSERT INTO t3 VALUES(234,567);
CREATE UNIQUE INDEX t3y ON t3(y);
DELETE FROM t3 WHERE y IS NULL;
SELECT * FROM t3;
}
} {234 567}
finish_test