sql经典练习题group by与同表关联组合应用

查询各科成绩前三名的记录

        select a.s_id,a.c_id,a.s_score from score a 
            left join score b on a.c_id = b.c_id and a.s_score<b.s_score
            group by a.s_id,a.c_id,a.s_score HAVING COUNT(b.s_id)<3
            ORDER BY a.c_id,a.s_score DESC

细细品很有感觉

---

-END-

如果你喜欢我的分享，欢迎关注微信公众号 java学长分享技术干货！

悄悄告诉你免费赠送重磅互联网架构师教程，提升职场技术水平！