我如何“声明标量变量"?在 Sql Server 中的 VIEW (2005) [英] How do I "Declare the scalar variable" in a VIEW in Sql Server (2005)

问题描述

我正在尝试在 SQL Server 2005 中创建一个 VIEW.

I´m trying to create a VIEW in SQL Server 2005.

SQL 代码是这样工作的(我在 VS2008 中使用它)，但在 SQL Server 中我无法保存它，作为错误消息声明标量变量@StartDate"和声明标量变量@结束日期"弹出.

The SQL code is working as such (I´m using it in VS2008), but in SQL Server I´m unable to save it, as error message "Declare the scalar variable @StartDate" and "Declare the scalar variable @EndDate" pops up.

代码如下:

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

而且我的问题当然是 - 我应该如何声明它们?

我尝试将以下内容放在代码中:

I tried to put the following first in the code:

DECLARE @StartDate smalldatetime
DECLARE @EndDate smalldatetime

但这并没有奏效，正如我所料 - 它只给了我另一个弹出消息:

But that didn´t do the trick, just as I expected - it only gave me another pop-up message:

不支持声明游标 SQL 构造或语句."

"The Declare cursor SQL construct or statement is not supported."

推荐答案

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.

As Alex K has mentioned, you should write it as a inline table valued function. Here is the article that describes about it.

简而言之，语法类似于

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

You can have one select query (however complex, can use CTE). And then you will use it as

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

这篇关于我如何“声明标量变量"?在 Sql Server 中的 VIEW (2005)的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！