1 <?xml version="1.0" encoding="UTF-8"?>
   2 <xsd:schema
   3   xmlns="IdConstrDefs/targetNS"
   4   xmlns:xsd="http://www.w3.org/2001/XMLSchema"
   5   targetNamespace="IdConstrDefs/targetNS">
   6 
   7   <xsd:element name="roota">
   8       <xsd:complexType>
   9           <xsd:sequence maxOccurs="unbounded">
  10               <xsd:element name="person"/>
  11           </xsd:sequence>
  12       </xsd:complexType>
  13       <xsd:key name="KEY">
  14           <xsd:selector xpath="./person"/>
  15           <xsd:field xpath="."/>
  16       </xsd:key>
  17       <xsd:keyref name="KEYREF" refer="KEY">
  18           <xsd:selector xpath="./person"/>
  19           <xsd:field xpath="@parent"/>
  20       </xsd:keyref>
  21   </xsd:element>
  22 
  23 </xsd:schema>