select v.tag, sum(if_retweet) as retweet_cnt, round(sum(if_retweet)/count(*),3) retweet_rate from tb_user_video_log u, tb_video_info v where u.video_id = v.video_id and datediff(date((select max(start_time) from tb_user_video_log)),date(u.start_time)) <=29 group by v.tag order by retweet_rate des...