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Fixed bug with UPDATE/DELETE on UNIQUE key which could be NULL

This commit is contained in:
monty@donna.mysql.fi
2001-04-10 11:32:28 +03:00
parent 7f21a7a6da
commit 3c82d4a2e1
7 changed files with 135 additions and 15 deletions

View File

@@ -45,3 +45,49 @@ select * from t1 where (a is null or a = 7) and b=7 and c=0;
select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
select * from t1 where b like "6%";
drop table t1;
#
# The following failed for Matt Loschert
#
DROP TABLE IF EXISTS t1,t2;
CREATE TABLE t1 (
id int(10) unsigned NOT NULL auto_increment,
uniq_id int(10) unsigned default NULL,
PRIMARY KEY (id),
UNIQUE KEY idx1 (uniq_id)
) TYPE=MyISAM;
CREATE TABLE t2 (
id int(10) unsigned NOT NULL auto_increment,
uniq_id int(10) unsigned default NULL,
PRIMARY KEY (id)
) TYPE=MyISAM;
INSERT INTO t1 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);
INSERT INTO t2 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);
#
# Check IS NULL optimization
#
explain select id from t1 where uniq_id is null;
explain select id from t1 where uniq_id =1;
#
# Check updates
#
UPDATE t1 SET id=id+100 where uniq_id is null;
UPDATE t2 SET id=id+100 where uniq_id is null;
select id from t1 where uniq_id is null;
select id from t2 where uniq_id is null;
#
# Delete all records from each table where the uniq_id field is null
#
DELETE FROM t1 WHERE uniq_id IS NULL;
DELETE FROM t2 WHERE uniq_id IS NULL;
#
# Select what is left -- notice the difference
#
SELECT * FROM t1 ORDER BY uniq_id, id;
SELECT * FROM t2 ORDER BY uniq_id, id;
DROP table t1,t2;