题解 | 每天登陆最早的用户的内容喜好

with min_tb as(
    select min(log_time) as mintime,
    date(log_time) as log_day
    from login_tb
    group by date(log_time)
),
e_user as(
    select log_day,user_id
    from min_tb join login_tb on min_tb.log_day=date(login_tb.log_time)
    where mintime=log_time
)
select log_day,user_id,hobby
from e_user join user_action_tb using(user_id)
order by log_day,user_id;