xml parameter to distributed query - difference between SQL2005 & SQL2012

Question

I have inherited an old SQL2005 Enterprise database (on Windows 2003) that allows an xml parameter to a distributed query such as this:

exec sp_executesql 'exec [server].[database].dbo.sproc @Id=@Id,@PItems=@PItems output','@PId bigint, @PItems xml output', valueOf@PId, valueOf@PItems output

This no longer works in SQL2012, the error says:

Msg 9512, Level 16, State 1, Line 1 Xml data type is not supported as a parameter to remote calls.

My question: is there a permission or tickbox (facet?) to allow xml parameters to distributed queries or does 2012 no longer support it?

Note: the tables do not have any columns of datatype xml. Only the parameter is xml.

Answer 1

I have found the solution to my problem. My "server name" part of the stored procedure was being loaded from a column in the database which included the port number (because it is a named instance), therefore it read

[Servername\Instance,Port].[database]....

but when I removed the port it worked. Demonstration below.

USE [master]
GO

CREATE DATABASE TestDatabase
go

ALTER DATABASE TestDatabase SET COMPATIBILITY_LEVEL = 90
GO

USE [TestDatabase]
go

CREATE TABLE [Table_A]([MyColumn] [varchar](100) NOT NULL)
go

INSERT INTO Table_A (MyColumn)
VALUES ('this is some text')
go


CREATE PROCEDURE [dbo].[GetSomeText] 
    @P_XmlParameter xml output
AS
BEGIN
    SET  @P_XmlParameter = (SELECT  MyColumn
                            FROM Table_A                                
                            FOR XML RAW('xmlrow'), ROOT('xmldoc'))
END
GO


CREATE PROCEDURE [dbo].[CallDistributedSproc] 
    @XmlParam xml output
AS
BEGIN

    declare @sql nvarchar(2000)
    declare @sqlparam nvarchar(2000)

    set @Sql = 'exec [' + @@SERVERNAME + '].[TestDatabase].dbo.GetSomeText @P_XmlParameter=@XmlParam output'

    set @SqlParam = '@XmlParam xml output'

    print @sql

    exec sp_executesql @Sql, @SqlParam, @XmlParam output
END
GO


declare @XmlParam xml
set @XmlParam= null
exec CallDistributedSproc @XmlParam=@XmlParam output
select @XmlParam

Answer 2

It's not supported, but you can get around it..

select * from openquery(
 LinkedServerName,
 'exec [database].dbo.sproc @Id=@Id,
                       @PItems=@PItems output'',''
                       @PId bigint, 
                       @PItems xml output'', 
                       valueOf@PId, 
                       valueOf@PItems output'
)

There are many pitfalls. which are well explained here, as you are on 2012 you will want to look into executing the remote query with results set. some version of this.

SELECT * FROM OPENQUERY(LinkedServerName, 
          'EXEC msdb..sp_helpindex sysjobs
           WITH RESULT SETS ((index_name        sysname,
                              index_description nvarchar(500),
                              index_keys        nvarchar(500)))')