1  <?xml version="1.0"?>
 2  <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
 3              xmlns:po="http://www.example.com/PO1"
 4  	    targetNamespace="http://www.example.com/PO1"
 5  	    elementFormDefault="unqualified"
 6  	    attributeFormDefault="unqualified">
 7    <xsd:annotation>
 8      <xsd:documentation xml:lang="en">
 9  Purchase order schema for Example.com.
10     Copyright 2000 Example.com. All rights reserved.
11      </xsd:documentation>
12    </xsd:annotation>
13    <xsd:element name="purchaseOrder" type="po:PurchaseOrderType"/>
14    <xsd:element name="comment" type="xsd:string"/>
15    <xsd:complexType name="PurchaseOrderType">
16      <xsd:sequence>
17        <xsd:element name="shipTo" type="po:USAddress"/>
18        <xsd:element name="billTo" type="po:USAddress"/>
19        <xsd:element ref="po:comment" minOccurs="0"/>
20        <xsd:element name="items" type="po:Items"/>
21      </xsd:sequence>
22      <xsd:attribute name="orderDate" type="xsd:date"/>
23    </xsd:complexType>
24    <xsd:complexType name="USAddress">
25      <xsd:sequence>
26        <xsd:element name="name" type="xsd:string"/>
27        <xsd:element name="street" type="xsd:string"/>
28        <xsd:element name="city" type="xsd:string"/>
29        <xsd:element name="state" type="xsd:string"/>
30        <xsd:element name="zip" type="xsd:decimal"/>
31      </xsd:sequence>
32      <xsd:attribute name="country" type="xsd:NMTOKEN" fixed="US"/>
33    </xsd:complexType>
34    <xsd:complexType name="Items">
35      <xsd:sequence>
36        <xsd:element name="item" minOccurs="0" maxOccurs="unbounded">
37          <xsd:complexType>
38            <xsd:sequence>
39              <xsd:element name="productName" type="xsd:string"/>
40              <xsd:element name="quantity">
41                <xsd:simpleType>
42                  <xsd:restriction base="xsd:positiveInteger">
43                    <xsd:maxExclusive value="100"/>
44                  </xsd:restriction>
45                </xsd:simpleType>
46              </xsd:element>
47              <xsd:element name="USPrice" type="xsd:decimal"/>
48              <xsd:element ref="po:comment" minOccurs="0"/>
49              <xsd:element name="shipDate" type="xsd:date" minOccurs="0"/>
50            </xsd:sequence>
51            <xsd:attribute name="partNum" type="po:SKU" use="required"/>
52          </xsd:complexType>
53        </xsd:element>
54      </xsd:sequence>
55    </xsd:complexType>
56  <!-- Stock Keeping Unit, a code for identifying products -->
57    <xsd:simpleType name="SKU">
58      <xsd:restriction base="xsd:string">
59        <xsd:pattern value="\d{3}-[A-Z]{2}"/>
60      </xsd:restriction>
61    </xsd:simpleType>
62  </xsd:schema>
63  
64