求一个关于分页的语句
SELECT TOP 20 5as ys,m.*,c.company_name FROM res_product_main as m left join company as c on m.manufacturer=c.cid WHERE (c.company_name like '%上海%') AND resproductkey>(SELECT MAX(resproductkey) FROM (SELECT TOP 80 resproductkey FROM res_product_main as m left join company as c on m.manufacturer=c.cid WHERE (c.company_name like '%上海%') ORDER BY resproductkey) t) ORDER BY resproductkey
上面这个语句 是求 第5页的 内容 ,每页20个,所以从第81个开始取 20个。 但发现很慢。一页比一页慢 求解决方法。