select tag,        sum(if_retweet) retweet_cnt,        round(sum(if_retweet)/count(*),3) retweet_ratefrom tb_user_video_log ljoin tb_video_info ion l.video_id = i.video_idwhere timestampdiff(day,start_time,(select max(start_time) from tb_user_video_log)) < 30group by tagorder by retweet_rate desc...