题解 | #找出每个学校GPA最低的同学#

#一步一步嵌套！！！！先把每个学校的最低gpa找出来
#在用内联 将设备筛选出来



select
    a.device_id,
    a.university,
    a.gpa
from
    user_profile a
inner join 
(select b.university,min(gpa) as min1
from
    user_profile b
group by university
order by university) as t
on a.gpa=t.min1
and a.university=t.university
order by university