题解 | #考试分数(二)#
考试分数(二)
https://www.nowcoder.com/practice/f456dedf88a64f169aadd648491a27c1
第一次把连接条件写成了a.id=b.id,后来发现应该是job,因为是job类分数之间的比较
select a.id,a.job,a.score from grade a left join ( select job,sum(score)*1.0/count(score) as t from grade group by job )b on a.job=b.job where a.score>b.t order by a.id