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我正在使用 SQL Server - 2005 ...

ALTER Proc [dbo].[ExamResult] (@Course_Id varchar(100), @Semester varchar(10))
as
begin
    declare @subjname varchar(100)  
    declare @subjects varchar(7000)  
    declare @subjectsselection varchar(7000)  
    declare @SumSelection varchar(7000)  
    declare @NoOfSubjects int
    set @NoOfSubjects = 0

    set @subjects = ''  
    set @subjectsselection = '' 
    set @SumSelection = ''

    DECLARE subject_cursor CURSOR  
    FOR SELECT distinct Subject_Name FROM Exam_Result where course_id = @Course_Id And Semester = @Semester 

    OPEN subject_cursor  

    FETCH NEXT FROM subject_cursor  
    INTO @subjname  

    WHILE @@FETCH_STATUS = 0  
    BEGIN  
        set @subjects = @subjects + '[' + @subjname + '],'  
        set @subjectsselection = @subjectsselection + 'Sum(Isnull([' + @subjname + '],0)) As [' + @subjname + '],' 
        set @SumSelection = @SumSelection + 'Sum(Isnull([' + @subjname + '],0))+' 

        set @NoOfSubjects = @NoOfSubjects + 1

        FETCH NEXT FROM subject_cursor  
        INTO @subjname  
    End  
    CLOSE subject_cursor;  
    DEALLOCATE subject_cursor;  

    select @subjects = LEFT(@subjects, LEN(@subjects) - 1)  
    select @subjectsselection = LEFT(@subjectsselection, LEN(@subjectsselection) - 1)  
    select @SumSelection = LEFT(@SumSelection, LEN(@SumSelection) - 1)  

    print @subjects  
    print @subjectsselection  
    print @SumSelection

    declare @query nvarchar(4000)  

    set @query = 'select S.Enroll_Number, pvt.Student_Name, pvt.Course_Id, pvt.Semester, ' + @subjectsselection + ',' 
    set @query = @query + 'Exam_Type,' + @SumSelection + ' As Grand_Total, '
    set @query = @query + '(' + @SumSelection + ')' + '/' + convert(varchar(10),@NoOfSubjects) + ' As Avg'
    set @query = @query + ' From '  
    set @query = @query + '(select Enroll_Number, Student_Name, Course_Id, Semester, Subject_Name, MarksObtained, Exam_Type from Exam_Result ) ps '  
    set @query = @query + ' pivot(sum(MarksObtained) for Subject_Name in (' + @subjects + ')) as pvt'  
    set @query = @query + ' inner join Stud_Info S on S.Enroll_Number = pvt.Enroll_Number '
    set @query = @query + ' where pvt.Course_Id = ''' + @Course_Id + ''' and pvt.Semester = ''' + @Semester + ''''
    set @query = @query + ' group by S.Enroll_Number, pvt.Student_Name, pvt.Course_Id, pvt.Semester, Exam_Type'
    print @query
    exec sp_executesql @query  
end

Exam_Result 表：

CREATE TABLE [dbo].[Exam_Result](
    [Result_Id] [int] IDENTITY(1,1) NOT NULL,
    [Enroll_Number] [varchar](50) NULL,
    [Student_Name] [varchar](100) NULL,
    [Course_Id] [varchar](50) NULL,
    [Semester] [varchar](50) NULL,
    [Subject_Id] [varchar](50) NULL,
    [Subject_Name] [varchar](50) NULL,
    [MarksObtained] [Varchar](10) NULL,
    [Exam_Type] [varchar](50) NULL)

样本数据查询...

INSERT into Exam_Result VALUES('11147','Mr.Mack28','CIV','1','PS1','ps1','60','Final')
INSERT into Exam_Result VALUES('11147','Mr.Mack28','CIV','3','PS1','ps1','70','Final')
INSERT into Exam_Result VALUES('11147','Mr.Mack28','CIV','3','PS1','ps1','80','Final')
INSERT into Exam_Result VALUES('11147','Mr.Mack28','CIV','3','PS1','ps1','20','Internal')
INSERT into Exam_Result VALUES('11147','Mr.Mack28','CIV','3','PS1','ps1','22','Internal')

Student_Info 表：我只用于检索到的 Student_Information，例如Enroll_Number ...

CREATE TABLE [dbo].[Stud_Info](
    [Enroll_Number] [varchar](20) NOT NULL,
    [Student_Name] [varchar](20) NULL,
    [Course_Type] [varchar](20) NULL,
    [Course_Id] [varchar](20) NULL,
    [Semester] [varchar](20) NULL,
    [Password] [varchar](20) NULL,
    [Gender] [varchar](6) NULL,
    [City] [varchar](15) NULL,
    [Mobile_Number] [varchar](10) NULL)

它给了我这样的错误......

消息 8117，级别 16，状态 1，行 1
操作数数据类型 varchar 对于求和运算符无效。

拉胡尔：根据你的回答，我更新了这样，但它仍然给出错误......

set @query = @query + ' pivot(sum(cast(MarksObtained as int)) for Subject_Name in (' + @subjects + ')) as pvt'

我认为它给出了错误，因为我正在使用MarksObtained列 ( as varchar(10)) ...请给我一个建议，我可以如何转换varchar，以便可以完成int总数的总和。MarksObtained

4

2 回答 2

3

You can convert like this way:

SUM (CONVERT(int,<your varchar column>))

This will work if your varchar column actually holds numeric value. Otherwise, you can try casting it using cast function like:

sum(cast(varchar_column as int))

EDIT:

Created a sample table with just 2 column (name and marksobtained), both of type varchar(10) and inserted some data to it. So that my select * looks like

name            marksobtained
Mr. Anil             30
Mr. sunil            70
Mr. patel            70

Summed the marks like

select SUM(cast(marksobtained as int)) as 'totalmarksobtained' from sampletab

Which returned 170.

What values does @subjects have? Post some sample.

于 2012-05-05T08:50:41.363 回答
0

您可以在查询中使用“cast”

例子：

select sum(cast(Enter_your_field_name as int)) from Table_name

希望对你有效。

于 2014-09-27T07:37:50.147 回答