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 ei.tag,ei.difficulty,
ROUND((SUM(er.score)-max(er.score)-MIN(score))/(count(er.score)-2),1)
clip_avg_score
FROM
examination_info ei
join
exam_record er
where ei.exam_id=er.exam_id
and ei.tag='SQL'
and ei.difficulty='hard'
