Question

我在MsAccess中有三个表如下：

Students(ID, Name, Class)
Subjects (ID, Name)
Marks (ID, StudentName[ID of Student], Subject.ID)

以及以下关系：

Marks.Subject = Subjects.ID
Marks.StudentID = Students.ID

我需要显示以下输出表：

--+--------------+---------------+--------------+--------------etc..
   Student Name    Subject1Name    Subject2Name   Subject1Name
--+--------------+---------------+--------------+--------------etc..

    jkki LastN       15                50               30
    XYZ LastN        25                60               70
    gui LastN        05                30               50

目前我有Follwing SQL：

Transform Marks.Obtained
SELECT Students.Name, Marks.Obtained
FROM (Students INNER JOIN (Marks INNER JOIN Subjects ON Marks.Subject = Subjects.ID)
ON Students.ID = Marks.StudentName)
GROUP BY  Students.Name, Marks.Obtained
Pivot Subjects.Name

它提供了与以下相同名称的重复输出：

--+--------------+---------------+--------------+--------------etc..
   Student Name    Subject1Name    Subject2Name   Subject1Name
--+--------------+---------------+--------------+--------------etc..

    jkki LastN       15               
    jkki LastN                          20      
    jkki LastN                                         05

通过Marks.Obtained从SQL中删除Group会产生以下错误：＆＃34;您尝试执行的查询不包含指定的表达式＆＃39;获取＆＃39;作为聚合函数的一部分＆＃34;

请帮我解决这个问题。

Answer 1

Transform应具有聚合功能。试试这个：

Transform MAX(Marks.Obtained)
SELECT Students.Name
FROM (Students INNER JOIN
      (Marks INNER JOIN
       Subjects
       ON Marks.Subject = Subjects.ID)
     ON Students.ID = Marks.StudentName)
GROUP BY Students.Name
Pivot Subjects.Name

在SQL中通过分组进行转换和透视

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