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
select answer_date,format(count((issue_id))*1.0/count(distinct(author_id)),2) per_num from answer_tb where substring(DATE_FORMAT(answer_date,'%Y-%m-%d'),6,2) ='11' group by answer_date