题解 | #最差是第几名(一)#不使用窗口函数也很简单

不使用窗口函数

SELECT
    a.grade,
    SUM(b.number)
FROM 
    class_grade a
JOIN class_grade b ON a.grade >= b.grade
GROUP BY a.grade
ORDER BY a.grade

使用窗口函数

SELECT
    grade,
    SUM(number) OVER(ORDER BY grade)
FROM  
    class_grade
ORDER BY grade