Hi Brad, Oooops. I think i better go and read your excelent book MySQL/PHP database applications agian...... Best regards,
Davy Obdam mailto:[EMAIL PROTECTED] Brad Bulger wrote: >what database are you using? because the answer is different, depending. > >on postgres, for example, which supports subselects, you can do > >select * from TableA where FieldA1 not in (select FieldB2 from TableB) > >with mysql, there are no subselects, so you'd have to do something like > >select TableA.*, TableB.FieldB1 >from TableA left join TableB on TableA.FieldA1 = TableB.FieldB1 >having FieldB1 is null > >PS the one thing that for sure will not work is > >select TableA.* from TableA, TableB where TableA.FieldA1 != TableB.FieldB2 > >that will just give you a cartesian product, returning a copy of >every row in TableA for every row in TableB that doesn't match its key > >On Sat, 12 Oct 2002, Christian Ista wrote: > > > >>Hello, >> >>I'm probably sleepy because I can't do a very easy query. :( >> >>I have 2 tables TableA(FieldA1, FieldA2, FieldA3) and TableB(FieldB1, >>FieldB2, FieldB3). >> >>I'd like to see the TableA records (FieldA2) where the FieldA1(Primary >>key) not exist in TableB(FieldB2). I tried "not exists" without success. >> >>Could you help me ? >> >>Christian, >> >> >>-- >>PHP General Mailing List (http://www.php.net/) >>To unsubscribe, visit: http://www.php.net/unsub.php >> >> >> > > > > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
