题解 | #每类视频近一个月的转发量/率#
每类视频近一个月的转发量/率
https://www.nowcoder.com/practice/a78cf92c11e0421abf93762d25c3bfad
select tag, sum(if_retweet), round(sum(if_retweet) / count(tag), 3) as zfl from tb_user_video_log a join tb_video_info b on a.video_id = b.video_id where start_time <=( select max(start_time) from tb_user_video_log ) and start_time>date_sub(( select max(start_time) from tb_user_video_log ),interval 30 day) group by tag order by zfl desc