oracle优化
1数据量比较小的表放在前边: select n.applyid from re_newafterloan n inner join re_apply a on a.applyid=n.applyid; select n.applyid from re_apply a inner join re_newafterloan n on a.applyid=n.applyid; 2整合sql,减少数据库的访问次数 select count(*) from re_bizcodecfg b where b.bizcodetype='zhonghang' ; select count(*) from re_bizcodecfg b where b.bizcodetype='signingModel' ; 整合后 select count(decode(bizcodetype,'zhonghang','x',null)) as avic,count(decode(bizcodetype,'signingModel','y',null)) as models from re_bizcodecfg (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |