完了,数据库忘光了(结果集条件查询)
两年来,神奇的只写过一种sql:select * form table where a = XX
结果以前的做统计时候的sql知识完全忘光了
今天想了一下午,才想起来还能这么写sql
select a.day,a.level ,a.roleNum,sum(b.roleNum) from t_game_roleNum a,t_game_roleNum b where a.day= b.dayand a.level <= b.level group by a.level ,a.day
