题解 | #各个视频的平均完播率#
各个视频的平均完播率
https://www.nowcoder.com/practice/96263162f69a48df9d84a93c71045753
order by 不能丢，having是对分组进行筛选
select u.video_id, round(sum(if(end_time - start_time >= duration, 1, 0)) / count(start_time), 3) avg_comp_play_rate from tb_user_video_log u left join tb_video_info i on u.video_id = i.video_id where year(start_time) = 2021 group by u.video_id order by avg_comp_play_rate desc;
