题解 | #找出每个学校GPA最低的同学#
找出每个学校GPA最低的同学
http://www.nowcoder.com/practice/90778f5ab7d64d35a40dc1095ff79065
select device_id, university, gpa from ( select device_id, university, gpa, rank() over (partition by university order by gpa) olap from user_profile ) a where a.olap = 1 order by university