摘要: select * from score a where sno in ( select sno from score group by sno having count(*)>1) --子查询 选多门课的同学 and degree<(select max(degree) from score b w 阅读全文
posted @ 2017-10-26 20:17 sistrong 阅读(3861) 评论(2) 推荐(0) 编辑