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
count(distinct XXX) 计数,不重复计算已经出现的
select answer_date, round(count(issue_id)/count(distinct author_id),2) per_num from answer_tb where month(answer_date) = 11 group by answer_date order by answer_date
