题解 | #平均播放进度大于60%的视频类别#

1. 输出% 需要用concat(...,'%')和replace(...,'%','')
2. 可能存在播放时长大于视频时长的情况，需要用IF(判断语句, 真则a, 假则b)
3. 播放时长要以秒为单位，用timestampdiff(second, start,end)

select tag,
    concat(
        round(
            avg(
                if (timestampdiff(second, start_time, end_time)/duration > 1, 100, timestampdiff(second, start_time, end_time)/duration*100)),
            2), 
            '%') as play_prop
from tb_user_video_log a
left join tb_video_info b
on a.video_id = b.video_id
group by tag
having replace(play_prop,'%','') > 60
order by play_prop desc