Question

我正在尝试选择使用sum的查询行。我不断收到错误column is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.我将指定的列添加到group by子句中，它只是转到查询中的下一列。我是否真的必须将select子句中的每一列添加到group by子句中？

这是我的疑问：

SELECT 
   s.studentId, s.firstName, s.lastName, 
   c.courseId, c.courseName, c.semesterId AS courseSemesterId, 
   se.semesterId, se.season, se.year, 
   e.enrollmentId, e.studentId AS enrolledStudentId, e.courseId AS enrolledCourseId, e.semesterId AS enrolledSemesterId,
   a.assignmentId, (sum(a.pointsEarned) / sum(a.pointsPossible)) AS percentage
FROM Students AS s
INNER JOIN Enrollment AS e ON s.studentId = e.studentId
LEFT JOIN Courses AS c ON e.courseId = c.courseId
LEFT JOIN Semesters AS se ON c.semesterId = se.semesterId
LEFT JOIN Assignments AS a ON e.enrollmentId = a.enrollmentId
GROUP BY s.studentId, s.firstName, s.lastName
ORDER BY e.courseId

Answer 1

不一定，如果您使用SQL Server 2012或更高版本（我相信），您可以使用OVER子句，如下所示：

(sum(a.pointsEarned) OVER (PARTITION BY s.studentId) / 
 sum(a.pointsPossible) OVER (PARTITION BY s.studentId))

链接到msdn文章：OVER Clause

Answer 2

试试这样。

方法-1

SELECT s.studentId
    ,s.firstName
    ,s.lastName
    ,(sum(a.pointsEarned) / sum(a.pointsPossible)) AS percentage
FROM Students AS s
INNER JOIN Enrollment AS e ON s.studentId = e.studentId
LEFT JOIN Courses AS c ON e.courseId = c.courseId
LEFT JOIN Semesters AS se ON c.semesterId = se.semesterId
LEFT JOIN Assignments AS a ON e.enrollmentId = a.enrollmentId
GROUP BY s.studentId
    ,s.firstName
    ,s.lastName
ORDER BY e.courseId

方法-2（如果您需要选择中的所有列。您应该将其包含在分组中）

SELECT s.studentId
    ,s.firstName
    ,s.lastName
    ,c.courseId
    ,c.courseName
    ,c.semesterId AS courseSemesterId
    ,se.semesterId
    ,se.season
    ,se.year
    ,e.enrollmentId
    ,e.studentId AS enrolledStudentId
    ,e.courseId AS enrolledCourseId
    ,e.semesterId AS enrolledSemesterId
    ,a.assignmentId
    ,(sum(a.pointsEarned) / sum(a.pointsPossible)) AS percentage
FROM Students AS s
INNER JOIN Enrollment AS e ON s.studentId = e.studentId
LEFT JOIN Courses AS c ON e.courseId = c.courseId
LEFT JOIN Semesters AS se ON c.semesterId = se.semesterId
LEFT JOIN Assignments AS a ON e.enrollmentId = a.enrollmentId
GROUP BY s.studentId
    ,s.firstName
    ,s.lastName
    ,c.courseId
    ,c.courseName
    ,c.semesterId
    ,se.semesterId
    ,se.season
    ,se.year
    ,e.enrollmentId
    ,e.studentId
    ,e.courseId
    ,e.semesterId
    ,a.assignmentId
ORDER BY e.courseId

column不包含在aggregate function或group by子句中

2 个答案: