如何使用 PIVOT 在 SQL Server 2005 中的动态列中声明变量

Question

我查看过this and this，但我迷路了。

出于某种原因，我无法声明要在以下动态列 SQL 代码中使用的 @wsDateFrom 和 @wsDateTo 变量。

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)

我收到的错误是

Must declare the scalar variable "@wsDateFrom".

但它就在那里！或者我应该以某种方式将 DECLARE 放在 @query 中吗？

如果是这种情况，那么我将如何在函数或存储过程中传递这两个日期变量？它会打开它进行 sql-注入，不是吗？

Answer 1

不，它不在那里。试试这个：

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)

如何使用 PIVOT 在 SQL Server 2005 中的动态列中声明变量

How to declare variables within dynamic columns in SQL Server 2005 using PIVOT

sql-server-2005

pivot

declare