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
select i.exam_id,
count(distinct e.uid) as uv,
round(avg(e.score),1)as avg_score
from user_info u
join exam_record e
on u.uid=e.uid
join examination_info i
on e.exam_id=i.exam_id
where i.tag='SQL' and u.level>5 and date_format(i.release_time,'%Y%m%d')=date_format(e.start_time,'%Y%m%d')
group by i.exam_id
order by uv desc,avg_score;
汤臣倍健公司氛围 420人发布