如何使用PIVOT在SQL Server 2005的動態列中聲明變量

Question

我已經簽出this和this，但我迷路了。

由於某些原因，我無法聲明@wsDateFrom & @wsDateTo在以下動態列SQL代碼中使用的變量。

DECLARE @cols AS NVARCHAR(MAX), 
     @query AS NVARCHAR(MAX) 

DECLARE @wsDateFrom AS smalldatetime 
DECLARE @wsDateTo AS smalldatetime 

SET @wsDateFrom = '01-JAN-2015' 
SET @wsDateTo = '30-JUN-2015' 

select @cols = STUFF((SELECT DISTINCT ',' + QUOTENAME(a.AbsenceDescription) 
         FROM dbo.tblAbsentCodes AS a 
         FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,'') 

set @query = N'SELECT StudentID, ' + @cols + 
      'FROM (SELECT a.StudentID, ab.AbsenceDescription, a.AttendanceID 
        FROM dbo.tblAttendance AS a 
         INNER JOIN tblCalendar c 
          ON a.DateID = c.DateID 
         INNER JOIN tblAbsentCodes as ab 
          ON ab.AbsenceID = a.AbsenceID 
        WHERE c.DayDate BETWEEN @wsDateFrom AND @wsDateTo) AS p 
       PIVOT (COUNT(AttendanceID) FOR AbsenceDescription IN (' + @cols + ')) AS pvt ' 

execute(@query) 

我得到的錯誤是

必須聲明標量變量 「@wsDateFrom」。

但它在那裏！或者我應該把@ DECLARE放在@query裏面？

如果是這種情況，那麼我將如何在函數或存儲過程中傳遞這兩個日期變量？它會打開它的SQL注入不是嗎？

Answer 1

不，它不在那裏。 試試這個：

DECLARE @cols AS NVARCHAR(MAX), 
     @query AS NVARCHAR(MAX) 

DECLARE @wsDateFrom AS smalldatetime 
DECLARE @wsDateTo AS smalldatetime 

SET @wsDateFrom = '01-JAN-2015' 
SET @wsDateTo = '30-JUN-2015' 

select @cols = STUFF((SELECT DISTINCT ',' + QUOTENAME(a.AbsenceDescription) 
         FROM dbo.tblAbsentCodes AS a 
         FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,'') 

set @query = N'SELECT StudentID, ' + @cols + 
      'FROM (SELECT a.StudentID, ab.AbsenceDescription, a.AttendanceID 
        FROM dbo.tblAttendance AS a 
         INNER JOIN tblCalendar c 
          ON a.DateID = c.DateID 
         INNER JOIN tblAbsentCodes as ab 
          ON ab.AbsenceID = a.AbsenceID 
        WHERE c.DayDate BETWEEN ' + @wsDateFrom + 'AND ' + @wsDateTo + ') AS p 
       PIVOT (COUNT(AttendanceID) FOR AbsenceDescription IN (' + @cols + ')) AS pvt ' 

execute(@query)