Sql server 2008 将用户定义的函数修改为视图

我继承了一个试图修改的用户定义函数，但遇到了一些问题。我想将其修改为常规查询，然后将其转换为视图。该函数是ufn_B2H_注册的客户列表。此函数用于在选定的时间段内提取程序中注册的客户端列表。在ufn_B2H_注册客户_列表中，是ufn_B2H_状态_至_DT的函数。这将选择客户机在所选时间范围内的最大状态更改，因此，如果客户机已注册，然后取消注册，然后再次注册，则函数不将其计入计数

我要做的是将ufn_B2H_已注册客户_列表转换为常规查询/视图，其输出如下所示：

Total_Clients_Enrolled     Month    Year 
252                         1      2013
247                         2      2013
303                         3      2013




**ufn_B2H_Enrolled_Clients_List Function**

RETURNS varchar(100)
AS
BEGIN
      -- Declare the return variable here
      DECLARE @VALUE varchar(100)
      SELECT  @VALUE = VALUE 
      FROM ENUMS
      WHERE NAME = @NAME AND NUMBER = @NUMBER
      IF @VALUE IS NULL
            SET @VALUE = 'unknown'
      RETURN (@VALUE)
END

GO


CREATE FUNCTION [dbo].[ufn_B2H_Enrolled_Clients_List](@From_DT datetime, @To_DT datetime)
RETURNS @retB2H_Enrolled_Clients_List TABLE 
(
  CLT_NBR int
  )
AS 
BEGIN 
      INSERT INTO @retB2H_Enrolled_Clients_List
    --Include all clients enrolled prior to the period end date


      SELECT CLT_NBR
      FROM ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s1
      WHERE s1.B2H_STATUS=4 AND s1.Max_Effect_DT <DATEADD(d,1,@To_DT)
            --Exclude all clients disenrolled or transferred out prior to the start date
            EXCEPT
            SELECT s2.CLT_NBR
            FROM ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s2 JOIN ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s1 ON s1.CLT_NBR=s2.CLT_NBR
            WHERE s2.B2H_STATUS IN (7,9) AND s2.Max_Effect_DT <@From_DT AND s2.Max_Effect_DT>s1.Max_Effect_DT AND s1.B2H_STATUS IN (4,8)
                  --Exclude all clients who transferred in after the prior end date.
                  EXCEPT
                  SELECT s3.CLT_NBR
                  FROM ECMS.dbo.B2H_STATUS s3 JOIN ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s1 ON s1.CLT_NBR=s3.CLT_NBR
                  WHERE s3.B2H_STATUS = 8 AND s1.B2H_STATUS IN (4,8) AND s3.EFFECT_DT > @To_DT AND s3.Effect_DT>s1.Max_Effect_DT

RETURN
END

GO

CREATE FUNCTION [dbo].[ufn_B2H_STATUSES_THROUGH_DT](@Through_DT datetime)
RETURNS @retB2H_STATUSES_THROUGH_DT TABLE 
(
   CLT_NBR int
  ,B2H_STATUS int
  ,Max_EFFECT_DT datetime
  )
AS 
BEGIN 
   INSERT INTO @retB2H_STATUSES_THROUGH_DT
       S


       ELECT CLT_NBR
               ,B2H_STATUS
               ,MAX(EFFECT_DT) AS Max_Effect_DT
            FROM [ECMS].[dbo].[B2H_STATUS]
            WHERE EFFECT_DT<DATEADD(d,1,@Through_DT)
            GROUP BY CLT_NBR, B2H_STATUS

RETURN
END

GO

由于dbo.ufn_B2H_已注册_Clients_List函数具有参数，因此可以将其转换为内联UDF，因此：

内联UDF是具有以下参数的视图：

内联函数可用于实现 参数化视图

参考资料：

CREATE FUNCTION [dbo].[ufn_B2H_Enrolled_Clients_List](@From_DT datetime, @To_DT datetime)
RETURNS TABLE 
AS 
RETURN
      SELECT CLT_NBR
      FROM ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s1
      WHERE s1.B2H_STATUS=4 AND s1.Max_Effect_DT <DATEADD(d,1,@To_DT)
            --Exclude all clients disenrolled or transferred out prior to the start date
            EXCEPT
            SELECT s2.CLT_NBR
            FROM ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s2 JOIN ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s1 ON s1.CLT_NBR=s2.CLT_NBR
            WHERE s2.B2H_STATUS IN (7,9) AND s2.Max_Effect_DT <@From_DT AND s2.Max_Effect_DT>s1.Max_Effect_DT AND s1.B2H_STATUS IN (4,8)
                  --Exclude all clients who transferred in after the prior end date.
                  EXCEPT
                  SELECT s3.CLT_NBR
                  FROM ECMS.dbo.B2H_STATUS s3 JOIN ECMS.dbo.ufn_B2H_STATUSES_THROUGH_DT(@To_DT) s1 ON s1.CLT_NBR=s3.CLT_NBR
                  WHERE s3.B2H_STATUS = 8 AND s1.B2H_STATUS IN (4,8) AND s3.EFFECT_DT > @To_DT AND s3.Effect_DT>s1.Max_Effect_DT

GO