题解 | #每个学校的平均年龄和平均绩点及整体情况#
每个学校的平均年龄和平均绩点及整体情况
https://www.nowcoder.com/practice/d686ac1d09d94441be91475843797d2d
select ifnull(university,'总体') as "university" , round(avg(age),3) as "avg_age", round(avg(gpa),3)as "avg_gpa" from user_profile group by university with rollup order by university;
将最后一行的rollup也计入university,同时通过ifnull函数改变其字段名称为总体。