题解 | #验证刷题效果，输出题目真实通过率#

select
    user_id,
    count(distinct if(result_info = 1, question_id, null)) / count(distinct question_id) question_pass_rate ,
    count(if(result_info = 1, question_id, null)) / count(question_id) pass_rate,
    count(question_id) / count(distinct question_id) question_per_cnt
from
    done_questions_record
group by
    user_id
having
    count(distinct if(result_info = 1, question_id, null)) / count(distinct question_id)>0.6