题解 | 每类视频近一个月的转发量/率
每类视频近一个月的转发量/率
https://www.nowcoder.com/practice/a78cf92c11e0421abf93762d25c3bfad
select tag,
sum(if_retweet) retweet_cnt,
round(sum(if_retweet)/count(*),3) retweet_rate
from tb_user_video_log l
join tb_video_info i
on l.video_id = i.video_id
where timestampdiff(day,start_time,(select max(start_time) from tb_user_video_log)) < 30
group by tag
order by retweet_rate desc
group by前的where子句不能用聚合函数，但是为什么我用having语句写不出来
