問題描述

$query = $this->db->query(’SELECT * , comments.rank1+comments.rank2+comments.rank3+comments.rank4 as ranksum,sites.id as id FROM sites inner join comments on sites.siteurl=comments.siteurl WHERE sites.tj<3 and sites.isshow=1 order by ranksum desc limit 10’);return $query->result_array();

comments.rank是針對(duì)站點(diǎn)的評(píng)價(jià)，每個(gè)頁(yè)面都有這一部分：在頁(yè)面右側(cè)顯示評(píng)價(jià)總分最高的10個(gè)站點(diǎn)。但是每個(gè)頁(yè)面都做這么一次查詢是不是不太好啊，能不能寫成索引的形式，求助大神

問題解答

SELECT *, comments.rank1 + comments.rank2 + comments.rank3 + comments.rank4 AS ranksum, sites.id AS idFROM sitesINNER JOIN comments ON sites.siteurl = comments.siteurlWHERE sites.tj < 3AND sites.isshow = 1ORDER BY ranksum DESCLIMIT 10