题解 | 查询连续登陆的用户

select user_id
from 
(
	select user_id
	,连续日期
	,count(连续日期) 天数
	from 
	(
		select user_id 
		,date_format(date_sub(log_time,interval r day),'%Y-%m-%d') 连续日期
		from 
		(
			select register_tb.user_id 
			,log_time
			,dense_rank()over(partition by register_tb.user_id order by log_time) r 
			from register_tb
			left join login_tb
			on register_tb.user_id = login_tb.user_id
		) a 
	)b 
	group by 1,2
) c 
where 天数 >= 3