我一直在挣扎着这一段时间。它花费了12秒钟,无法弄清楚为什么,因为所有三张桌子都有长袍,所以它变慢了很多。非常缓慢的Mysql SELECT查询
SELECT SUM(quantity), rprice, media_file, url, title
FROM inventory, ndxz_objects, ndxz_media
WHERE productid = ndxz_objects.id
AND media_ref_id = ndxz_objects.id
AND productid = media_ref_id
AND media_order = (SELECT MIN(media_order) FROM ndxz_media WHERE media_ref_id = ndxz_objects.id)
GROUP BY productid
ORDER BY productid DESC
即使世界上ndxz_objects.id
我猜你也需要在最低限度,在ndxz_media.media_ref_id
索引的索引和productid
什么解释(.. your_query_here ..)说什么?也许将它粘贴在这里,以便我们可以更好地了解性能指标在哪里 – Jaime 2010-11-27 21:50:32