select b.tag, concat((round(avg(case when timestampdiff(second,a.start_time,a.end_time)>=b.duration then 1 else (timestampdiff(second,a.start_time,a.end_time))/b.duration end)*100,2)),"%") as avg_play_progress from tb_user_video_log as a left join tb_video_info as b on a.video_id=b.vi...