1<?xml version="1.0" encoding="UTF-8" ?> 
2<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
3           targetNamespace="http://www.tempuri.org/MainSchema"
4           xmlns:tns="http://www.tempuri.org/MainSchema"
5           xmlns:ns="http://www.tempuri.org/ImportedSchema"
6           elementFormDefault="qualified" >
7           
8  <xs:import namespace="http://www.tempuri.org/ImportedSchema" schemaLocation="/import-455953.xsd" />
9  
10  <xs:complexType name="MyMainType">
11    <xs:sequence>
12      <xs:element name="MainA">
13        <xs:complexType>
14          <xs:attribute name="MainID" type="xs:int"/>
15        </xs:complexType>
16      </xs:element>
17      <xs:element ref="ns:AnotherElement" />
18    </xs:sequence>
19  </xs:complexType>
20
21  <xs:element name="MainElement" type="tns:MyMainType">
22    <xs:key name="MainKey" >
23      <xs:selector xpath="tns:MainA" />
24      <xs:field xpath="@MainID" />
25    </xs:key>
26  </xs:element>
27
28
29</xs:schema>
30