题解 | #SQL类别高难度试卷得分的截断平均值#
SQL类别高难度试卷得分的截断平均值
http://www.nowcoder.com/practice/a690f76a718242fd80757115d305be45
select
tag
,difficulty
,round((sum(score)-max(score)-min(score))/(count(score)-2),1) clip_avg_score
from exam_record r
join examination_info i
on r.exam_id=i.exam_id
tag
,difficulty
,round((sum(score)-max(score)-min(score))/(count(score)-2),1) clip_avg_score
from exam_record r
join examination_info i
on r.exam_id=i.exam_id
and r.exam_id=9001
看到别人用平均的方法,看来要多灵活运用。