题解 | #找出每个学校GPA最低的同学#

select up.device_id,university,up.gpa
from user_profile up
join 
(select device_id,gpa,
row_number() over(partition by university order by gpa )rk
from user_profile
)ui
on up.device_id=ui.device_id
where rk=1
order by university;

窗口函数确实好用