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xmlsql-server-2008for-xml

SQL Server FOR XML Enclosing Element?


Using SQL Server 2008, I have a query that emits a result set using FOR XML. Right now it is a non-compliant fragment.

How can I wrap my result XML in an enclosing element and then put a simple XML declaration on top with a single schema/namespace reference to make the output compliant?

Thanks.


Solution

  • It is not possible to have the XML processing instruction in a XML datatype in SQL Server.

    See Limitations of the XML Data Type

    This code

    declare @XML xml =  
      '<?xml version="1.0"?>
       <root>Value</root>'
    
    select @XML
    

    Has the output

    <root>Value</root>
    

    You can build the XML as a string with the XML processing instruction in place.

    declare @XML xml = '<root>Value</root>'
    declare @XMLStr nvarchar(max) = '<?xml version="1.0"?>'
      
    set @XMLStr = @XMLStr + cast(@XML as nvarchar(max))
    
    select @XMLStr
    

    Output

    --------------------------------------------------------------------------
    <?xml version="1.0"?><root>Value</root>