题解 | 某乎问答11月份日人均回答量
某乎问答11月份日人均回答量
https://www.nowcoder.com/practice/d1f5a1e50d0b49f3a39eb01c4fdb621f
首先陈列出每天每人回答问题；
然后sum每天的问题数，count每天的人数，做个除法就好啦。
select answer_date,round(sum(cnt)/count(1),2) as per_num
from
( select answer_date,author_id,count(1) as cnt
from answer_tb
group by answer_date,author_id) as t
group by answer_date
查看12道真题和解析