# 注意：人均浏览时长 = 总时长/去重用户数


select date(in_time) dt,
       round(sum(timestampdiff(second, in_time, out_time))/count(distinct uid),1) as avg_viiew_len_sec
from tb_user_log
where (date(in_time) between "2021-11-01" 
                     and "2021-11-30") 
        and artical_id != 0
group by dt
order by  avg_viiew_len_sec