我使用SQL服務器 - 2005 ...操作數的數據類型爲varchar是和運算無效 - 程序糾錯
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)
的樣本數據查詢 ...
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:我只是使用檢索Student_Information像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)
它給了我這樣的錯誤...
消息8117,級別16,狀態1,第1行
對於sum運算符,操作數數據類型varchar無效。
拉胡爾:根據你回答我更新這樣的,但它仍然給錯誤......
set @query = @query + ' pivot(sum(cast(MarksObtained as int)) for Subject_Name in (' + @subjects + ')) as pvt'
我想這是因爲我使用的是MarksObtained
列給出錯誤(as varchar(10)
)... PLZ給我一個建議,我可以如何將varchar
轉換爲int
,以便總計MarksObtained
的總和可以完成。
如果該列包含整數值,爲什麼您將其聲明爲VARCHAR? – Oded
上次v已命令將其標記爲varchar以防在任何學生缺席該主題的情況下,那麼我們必須插入ABS ... dats方式我想將其轉換爲 – mack28
然後在應用程序中將其轉換爲** ** 。不要將其存儲在數據庫中。 – Oded