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题目#xff1a;现在运营想要了解浙江大学的用户在不同难度题目下答题的正确率情况#xff0c;请取出相应数据#xff0c;并按照准确率升序输出。
示例#xff1a; user_profile
iddevice_idgenderageuniversitygpaactive_days_within_30question_cntanswer_cnt121…描述
题目现在运营想要了解浙江大学的用户在不同难度题目下答题的正确率情况请取出相应数据并按照准确率升序输出。
示例 user_profile
iddevice_idgenderageuniversitygpaactive_days_within_30question_cntanswer_cnt12138male21北京大学3.4721223214male复旦大学41552536543female20北京大学3.21233042315female23浙江大学3.651255432male25山东大学3.820157062131male28山东大学3.31571374321female26复旦大学3.69652
示例 question_practice_detail
iddevice_idquestion_idresult12138111wrong23214112wrong33214113wrong46543111right52315115right62315116right72315117wrong
示例 question_detail
question_iddifficult_level111hard112medium113easy115easy116medium117easy
根据示例你的查询应返回以下结果
difficult_levelcorrect_rateeasy0.5000medium1.0000
with cte as(select question_id,device_id,result,difficult_levelfromquestion_practice_detail left join user_profile using(device_id)left join question_detail using(question_id)where university浙江大学
)select
difficult_level,
ifnull(sum(if(resultright,1,0))/count(result),0) as correct_rate
from cte
group by difficult_level
order by correct_rate
