Allow only other existing XML values in XSD? (xs:key and xs:keyref)
Let's take the following example XML: <device> <name>NiceDevice</name> <value>123</value> </device> <user> <name>user1</name> <usesDevice>NiceDevice</usesDevice> </user> <user> <name>user2</name> <usesDevice>NiceDevice</usesDevice> </user> validated by this XSD: <xs:element name="device" minOccurs="0" maxOccurs="unbounded"> <xs:complexType> <element name="name" type="xs:string"/> <element name="value" type="xs:integer"/> </xs:complexType> </xs:element> <xs:element name="user" minOccurs="0" maxOccurs="unbounded"> <xs:complexType> <element name="name" type="xs:string"/> <element name="usesDevice