2.1.2.8 [ISO/IEC9075-14:2011] X013, Distinct types of XML type

V0043:

The specification states the following:

 Subclause 12.6, "<user-defined type definition>":
  
 Without Feature X013, "Distinct types of XML type", conforming SQL language shall not contain a <representation> that is a <predefined type> that is an XML type.

Microsoft SQL Server 2008 R2 and Microsoft SQL Server 2012 vary as follows:

Transact-SQL does not support this feature. However, Transact-SQL supports user-defined alias types that have some equivalent functionality. For more information, see feature S011 in [MS-TSQLISO02].

This variation pertains to xml data type functionality in SQL Server.