题解 | #SQL类别高难度试卷得分的截断平均值#

保留一位 (count（ss）,1)

select tag, difficulty, 
    round((sum(score) - max(score) - min(score)) / (count(score) - 2), 1) as clip_avg_score
from exam_record
join examination_info using(exam_id)
where tag = 'SQL' and difficulty = 'hard';