Hi, On Wed, Mar 5, 2008 at 9:11 AM, Johan Thorvaldsson <[EMAIL PROTECTED]> wrote: > I need help to optimize this following query. It runs very slow and I cant > find any direct errors in it. > SELECT > 1 * t1.termfreq as viktatantal, > t1.tag, t1.url FROM tag_keys t1 > LEFT JOIN tag_ad_map tm1 ON t1.id = tm1.tag_id > LEFT JOIN tag_ad_map tm2 ON tm1.ad_id = tm2.ad_id > LEFT JOIN tag_keys t2 ON t2.id = tm2.tag_id > WHERE > t2.url = 'motor' AND t1.url != 'motor' > GROUP BY t1.id > ORDER BY viktatantal DESC, RAND() > LIMIT 80 > > Any help would be very appriciated!
You should use EXPLAIN. If you don't understand the output of EXPLAIN, post the output back to this list and we can help you understand it. Cheers Baron -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]