select tag, avg_play_progress from ( select tag, video_id, concat (round(avg(rate) * 100, 2), '%') as avg_play_progress from ( select tag, video_id, if(times / duration>=1,1,times / duration) as rate from ( select i.tag, l.id, l.uid, l.video_id, timestampdiff (second, l.start_time, l.end_time) as...