select date_format(in_time,'%Y-%m-%d')dt, round(sum(timestampdiff(second,in_time,out_time))/count(distinct uid),1) avg_viiew_len_sec
from tb_user_log
where year(in_time)=2021 and month(in_time)=11
and artical_id != 0
group by date_format(in_time,'%Y-%m-%d')
order by avg_viiew_len_sec
  • 注意每人的平均时长
  • 要用总时长除以总人数