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
https://www.nowcoder.com/practice/a690f76a718242fd80757115d305be45
select tag,difficulty,round(avg(score),1) as cilp_avg_score
from (
select tag,difficulty,score,
rank() over (order by score )as rank_min,
rank() over (order by score desc) as rank_max
from examination_info a,exam_record b
where a.exam_id = b.exam_id
and a.tag = "SQL"
and a.difficulty = "hard"
and score is not null) as t1
where rank_min !=1 and rank_max != 1
group by tag;
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