SQL SERVER FOR XML EXPLICIT

Question

I want to assign the result of a SELECT FOR XML EXPLICIT statement to a XML Variable such as

CREATE PROCEDURE BILLING_RESPONSE 
AS   DECLARE @Data AS  XML

SET @Data = (SELECT

                1 AS Tag,
                NULL AS Parent,
                NULL AS 'CallTransactions!1!',
                NULL AS 'TCALTRS!2!TRS_DAT_TE!cdata',
                NULL AS 'TCALTRS!2!TRS_CRT_DT!Element'
            UNION ALL
            SELECT
                2 AS Tag,
                1 AS Parent, 
                NULL, 
                TRS_DAT_TE,
                TRS_CRT_DT  
             FROM TCALTRS 
             WHERE TRS_CRT_DT between CONVERT(date,GETDATE()-1) and CONVERT(date,getdate()) and 
             TRS_DAT_TE like '%(Submit Response)%'  
             FOR XML EXPLICIT           
            )

SELECT @DATA
GO

When i execute this query am getting the following error Msg 1086, Level 15, State 1, Procedure BILLING_RESPONSE, Line 22 The FOR XML clause is invalid in views, inline functions, derived tables, and subqueries when they contain a set operator. To work around, wrap the SELECT containing a set operator using derived table syntax and apply FOR XML on top of it.

Answer 1

The error is not particularly clear, but what it is saying is that you can't use the FOR XML clause in the inline subquery because it contains a UNION (a type of set operator)

The suggested workaround is to wrap the subquery in something else and call it separately, for example:

CREATE PROCEDURE BILLING_RESPONSE 
AS   DECLARE @Data AS  XML

;WITH DATA AS(
               SELECT
                1 AS Tag,
                NULL AS Parent,
                NULL AS 'CallTransactions!1!',
                NULL AS 'TCALTRS!2!TRS_DAT_TE!cdata',
                NULL AS 'TCALTRS!2!TRS_CRT_DT!Element'
            UNION ALL
            SELECT
                2 AS Tag,
                1 AS Parent, 
                NULL, 
                TRS_DAT_TE,
                TRS_CRT_DT  
             FROM TCALTRS 
             WHERE TRS_CRT_DT between CONVERT(date,GETDATE()-1) and CONVERT(date,getdate()) and 
             TRS_DAT_TE like '%(Submit Response)%'  
             FOR XML EXPLICIT           
            )
SELECT @Data = (SELECT * FROM DATA FOR XML EXPLICIT)
SELECT @DATA
GO

Answer 2

If this is it, you don't need the @Data variable. Let your sp return the result of query directly and you're done.

CREATE PROCEDURE BILLING_RESPONSE AS
SELECT

        1 AS Tag,
        NULL AS Parent,
        NULL AS 'CallTransactions!1!',
        NULL AS 'TCALTRS!2!TRS_DAT_TE!cdata',
        NULL AS 'TCALTRS!2!TRS_CRT_DT!Element'
    UNION ALL
    SELECT
        2 AS Tag,
        1 AS Parent, 
        NULL, 
        TRS_DAT_TE,
        TRS_CRT_DT  
     FROM TCALTRS 
     WHERE TRS_CRT_DT between CONVERT(date,GETDATE()-1) and CONVERT(date,getdate()) and 
     TRS_DAT_TE like '%(Submit Response)%'  
     FOR XML EXPLICIT