题解 | #平均播放进度大于60%的视频类别#

select tag,
concat(round(avg(if(timestampdiff(second, start_time, end_time) > duration, 1, timestampdiff(second, start_time, end_time) / duration)) * 100, 2), '%') avg_play_progress
from tb_user_video_log a left join tb_video_info b on a.video_id = b.video_id
group by tag
having avg(if(timestampdiff(second, start_time, end_time) > duration, 1, timestampdiff(second, start_time, end_time) / duration)) > 0.6
order by 2 desc

本人没有使用子查询，而是用表连接，直接对一整个大表进行查询；值得注意的是，保留两位小数的时候，应该先乘100再round，这样才能保证数值准确！以下是具体步骤：