with t1 as (select video_id,substring(start_time,1,7) months,if_follow from tb_user_video_log where YEAR(start_time)=2021), t2 as (select t1.*,tb.author,count(if_follow) over(partition by t1.months,tb.author) cnt from t1 inner join tb_video_info tb on t1.video_id=tb.video_id), t3 as (select distinct...