Hmm, Looking at the link http://www.artfulsoftware.com/infotree/queries.php and explanations here, EXISTS() should have performed better, but does not seem to??? I stopped it after about 5 minutes.
I tried both: SELECT * FROM A WHERE EXISTS (SELECT * FROM B WHERE A.id=B.A_ID and B.name like 'X%'); and SELECT * FROM A WHERE EXISTS (SELECT B.A_ID FROM B WHERE A.id=B.A_ID and B.name like 'X%'); Both are slow... On Sat, Jul 7, 2012 at 8:34 AM, Rik Wasmus <r...@grib.nl> wrote: >> See "The unbearable slowness of IN()" at >> http://www.artfulsoftware.com/infotree/queries.php > > > Do you read your own links? Excerpt: > >> In 5.0, EXISTS() is much faster than IN(), but slower than JOIN. In 5.5, > EXISTS() performs about as well as JOIN. > > So.... judging by the subject line... > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/mysql > -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql
