Question

我继承了一个用户定义的函数，我正在尝试修改并遇到一些麻烦。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_Enrolled_Clients_List。此函数在选定的时间段内提取在程序中注册的客户端列表。 ufn_B2H_Enrolled_Clients_List 中的函数是 ufn_B2H_STATUSES_THROUGH_DT 。这将选择客户端在所选时间范围内的最大状态更改，因此，如果客户端已注册，然后已取消注册，然后再次注册，则该功能不会将其用于计数。

我想要的是将ufn_B2H_Enrolled_Clients_List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

Answer 1

由于dbo.ufn_B2H_Enrolled_Clients_List函数有参数，您可以将其转换为内联UDF，因此：

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

内联UDF是一个带参数的视图：

内联函数可用于实现功能参数化视图。

参考文献：http://technet.microsoft.com/en-us/library/aa214762(v=sql.80).aspx

将用户定义的功能修改为视图

1 个答案: