题解 | #找出每个学校GPA最低的同学#

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

select device_id, university, gpa
from (
    select device_id,university,gpa,
    row_number() over (partition by university order by gpa asc) as rn
    from user_profile
) as univ_min
where rn=1
order by university