select a.video_id,round( sum(if (end_time - start_time >= duration, 1, 0)) / count(start_time), 3 ) as avg_comp_play_rate from tb_user_video_log a left join tb_video_info b on a.video_id = b.video_id where year (a.start_time) = 2021 group by a.video_id order by avg_comp_play_rate DESC 题目要求，关键步骤是算...
