XML Schema - redefine

["Morcom, Harvey" <Harvey.Morcom@KPMG.co.uk>]

Is it possible to use <redefine> to extend a simpleType using union? I have tried to achieve this using the approach below but with no luck, does anybody know where I am going wrong?

For example, 
Schema_A.xsd contains the simpleType
	<xsd:simpleType name="myString">
		<xsd:restriction base="xsd:string">
			<xsd:enumeration value="Football"/>
			<xsd:enumeration value="Rugby"/>
		</xsd:restriction>
	</xsd:simpleType>

Schema_B.xsd extends this datatype using union
	<xs:import namespace="http://foo/sports"; schemaLocation="Schema_C.xsd"/>
	<xsd:redefine schemaLocation="Schema_A.xsd">
		<xsd:simpleType name="myString">
			<xsd:union memberTypes="myString foo:Sports"/>
		</xsd:simpleType>
	</xsd:redefine>  

Schema_C.xsd contains the new dataType
	<xsd:simpleType name="Sports">
		<xsd:restriction base="xsd:string">
			<xsd:enumeration value="Elephant Wrestling"/>
		</xsd:restriction>
	</xsd:simpleType>

Thanks in advance
Harvey

> Harvey Morcom
> Knowledge Analyst
> harvey.morcom@kpmg.co.uk
> Tel: 782 8695 (020 7694 8695)
> 


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