You should use "IS NULL" or "IS NOT NULL" query. -- Chung Ha-nyung <alita@[neowiz.com|kldp.org]> SayClub <http://www.sayclub.com> NeoWiz <http://www.neowiz.com>
> -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] > Sent: Wednesday, November 20, 2002 1:45 AM > To: [EMAIL PROTECTED] > Subject: delete where column <=> null > > > Hi, > > I'm trying to delete from a table where col <=> null, but it doesn't > seem to work. I don't see anything in the manual that says that <=> > can't be used in the where clause of a delete statment, but: > > > mysql> select * from t; > +----+------+ > | id | num | > +----+------+ > | 1 | NULL | > | 1 | NULL | > +----+------+ > 4 rows in set (0.00 sec) > > mysql> delete from t where id = 1 and num <=> null; > Query OK, 0 rows affected (0.00 sec) > > mysql> select * from t where id = 1 and num <=> null; > +----+------+ > | id | num | > +----+------+ > | 1 | NULL | > | 1 | NULL | > +----+------+ > 2 rows in set (0.00 sec) > > > > This behavior seems very bizarre and counter-intuitive to me, but it's > such an obvious bug that I'm afraid it must be a feature and not a > bug. Can anyone help/explain? > > Using "is null" in the where clause works, of course, but would be > relatively cumbersome to use. > > Db is 3.23.53-max-nt > > Thanks, > > -David > > p.s. in case it's relevant, there is a unique index on (id,num): > > create table t ( > id integer not null, > num integer, > unique index id_num_idx(id,num) > ); > > > --------------------------------------------------------------------- > Before posting, please check: > http://www.mysql.com/manual.php (the manual) > http://lists.mysql.com/ (the list archive) > > To request this thread, e-mail <[EMAIL PROTECTED]> > To unsubscribe, e-mail > <[EMAIL PROTECTED]> > Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php > > > --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
