方法一：

with min_time_user as (
select user_id,log_time
from login_tb
where log_time in (
select min(log_time) as min_time
from login_tb 
group by date(log_time)))

select date(m.log_time) as log_day,m.user_id,u.hobby
from min_time_user m inner join user_action_tb u on m.user_id = u.user_id
order by log_day