题解 | #每篇文章同一时刻最大在看人数#
每篇文章同一时刻最大在看人数
https://www.nowcoder.com/practice/fe24c93008b84e9592b35faa15755e48
#统计<每篇文章><同一时刻>《最大》在看人数,如果同一时刻有进入也有离开时,先记录用户数增加再记录减少,结果按最大人数降序。 with t as (select t1.artical_id, sum(t1.uv) over (partition by t1.artical_id order by t1.time, t1.uv desc )as online_uv from (select artical_id, in_time as time ,1 as uv from tb_user_log union all select artical_id, out_time as time ,-1 as uv from tb_user_log )as t1 where artical_id<>0 ) select t.artical_id, max(online_uv) as max_uv from t group by artical_id order by max_uv desc;