题解 | #试卷发布当天作答人数和平均分#
试卷发布当天作答人数和平均分
http://www.nowcoder.com/practice/5b58e89556dc4153a79d8cf8c08ba499
两次left join表连接
select exam_id,count(distinct ui.uid) as uv,round(avg(score),1) as avg_score
from exam_record
left join user_info ui using(uid)
left join examination_info using(exam_id)
where tag='SQL'
and level>5
and date_format(submit_time,'%Y%m%d')=date_format(release_time,'%Y%m%d')
group by exam_id
order by uv desc,avg_score
蔚来一面51人在聊
查看15道真题和解析
投递蓝月亮等公司7个岗位 >