hi.sorry to borther again
I want to ask how to rewrite those statement ,too.
Like '>,<,LIMIT '.
And when I use 'order by ' how to change the order of 'ASC,DESC'?
Thanks very much.
vanessa lee
-----Original Message----- From: Roan Kattouw roan.kattouw@gmail.com To: Wikimedia developers wikitech-l@lists.wikimedia.org Date: Thu, 26 Nov 2009 13:32:10 +0100 Subject: Re: [Wikitech-l] SQL
2009/11/26 Tim Starling tstarling@wikimedia.org:
Don't use subselects, they're not supported by MySQL 4.0 which is what we target.
$dbr = wfGetDB( DB_SLAVE );
$max = $dbr->selectField( 'recentchanges', 'max(rc_id)', false, __METHOD__, array( 'GROUP BY' => 'rc_title' );
$res = $dbr->select( 'recentchanges', '*', array( 'rc_id' => $max, 'rc_namespace' => 0, 'rc_title' => 'Wiki', ), __METHOD__ );
Note that the GROUP BY condition in the first query is unnecessary, and that the whole thing could be rewritten to SELECT * FROM recentchanges WHERE rc_namespace=0 AND rc_title='Wiki' ORDER BY rc_id DESC LIMIT 1;
Roan Kattouw (Catrope)
_______________________________________________ Wikitech-l mailing list Wikitech-l@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikitech-l