From: Peter Brawley Date: October 26 2007 4:47pm Subject: Re: Comparing keys in two tables List-Archive: http://lists.mysql.com/mysql/209709 Message-Id: <47221A12.8030601@earthlink.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Aaron >The "left join on" took .1919 seconds and the "left outer join as" took .1780 seconds. Caching :) PB ----- Aaron Fischer wrote: > Thanks Peter and Baron, these both worked well. > > The "left join on" took .1919 seconds and the "left outer join as" > took .1780 seconds. > > =) > > > On Oct 26, 2007, at 11:37 AM, Peter Brawley wrote: > >> Aaron >> >> An exclusion join: >> >> SELECT a.col >> FROM a >> LEFT JOIN b ON a.col=b.col >> WHERE b.col IS NULL; >> >> PB >> > >