Re: multiple tables and amounts

hi! thanks a lot for your answer. i also thought of dividing the problem into several selects, but the application i'm working with (it's designed by a friend of mine, which lets you easily generate XML out of an sql) only accepts one single query.. do you know about any problems using CREATE TEMPORARY TABLE - eg. when there are a lot of users accessing the page? thx for your help again! -mathew # die welt ist schnell geworden... > Von: "Hutchins, Richard" <Richard.Hutchins@Getingeusa.com> > Antworten an: Richard.Hutchins@Getingeusa.com > Datum: Thu, 29 Jan 2004 08:25:03 -0500 > An: "'grillen@abendstille.at'" <grillen@abendstille.at> > Betreff: RE: [PHP-DB] multiple tables and amounts > > Matt, > > What about this (assuming MySQL): > > //$photoid is whatever photo you want the details for. > $sql_a = "SELECT id FROM comments WHERE phid = '".$photoid."'"; > $sql_b = "SELECT id FROM ratings WHERE phid = '".$photoid."'"; > > $result_a = mysql_query($sql_a) or > die(mysql_error()); > $num_comments = mysql_num_rows($result_a); > > $result_b = mysql_query($sql_b) or > die(mysql_error()); > $num_ratings = mysql_num_rows($result_b); > > echo "There were ".$num_comments." comments and ".$num_ratings." for > that > photo."; > > Since you're not doing anything really difficult with the queries, you > probably won't see much of a speed hit by doing back-to-back queries like > this. Besides, I think doing two straight queries like this is going to be > faster than creating and deleting temporary tables. Just a guess.