如何在Sql Server(2005)的VIEW中"声明标量变量"

Question

我正在尝试在SQL Server 2005中创建一个VIEW.

SQL代码正在这样工作(我在VS2008中使用它),但在SQL Server中我无法保存它,因为错误消息"声明标量变量@StartDate"和"声明标量变量@EndDate"弹出起来.

这是代码:

WITH Calendar AS (SELECT     CAST(@StartDate AS datetime) AS Date
     UNION ALL
     SELECT     DATEADD(d, 1, Date) AS Expr1
     FROM         Calendar AS Calendar_1
     WHERE     (DATEADD(d, 1, Date) < @EndDate))
    SELECT     C.Date, C2.Country, COALESCE (SUM(R.[Amount of people per day needed]), 0) AS [Allocated testers]
     FROM         Calendar AS C CROSS JOIN
                            dbo.Country AS C2 LEFT OUTER JOIN
                            dbo.Requests AS R ON C.Date BETWEEN R.[Start date] AND R.[End date] AND R.CountryID = C2.CountryID
     GROUP BY C.Date, C2.Country

而我的问题当然是-我应该究竟如何申报呢？

我试着在代码中首先放入以下内容:

DECLARE @StartDate smalldatetime
DECLARE @EndDate smalldatetime

但就像我预期的那样,这没有做到这一点 - 它只给了我另一个弹出消息:

"不支持Declare游标SQL构造或语句."

Answer 1

正如Alex K所提到的,您应该将其编写为内联表值函数.这是描述它的文章.

简而言之,语法就像

CREATE FUNCTION dbo.GetForPeriod
    ( @StartDate datetime, @EndDate datetime) 
RETURNS TABLE 
RETURN 
   SELECT  [[ your column list ]]
   FROM    [[ table list]
   WHERE   [[some column] BETWEEN @StartDate AND @EndDate

您可以有一个选择查询(无论多么复杂,都可以使用CTE).然后你会用它作为

SELECT * FROM dbo.GetForPeriod('1-Jan-2010', '31-Jan-2010')