一个scheme 的例子

<?xml version="1.0" encoding="UTF-8"?>
<schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.travelsky.com/pnrSchema" xmlns:tns="http://www.travelsky.com/pnrSchema" elementFormDefault="qualified">
    <complexType name="PnrInfoDef">
        <sequence>
            <element name="RLC" minOccurs="1" maxOccurs="1"
                type="tns:RLCDef">
            </element>
            <element name="CreateDate" type="dateTime" minOccurs="1"
                maxOccurs="1">
            </element>
            <element name="Group" type="boolean" minOccurs="1"
                maxOccurs="1">
            </element>

            <element name="Cancelled" type="boolean" minOccurs="1"
                maxOccurs="1">
            </element>
            <element name="UpdateDate" type="dateTime" maxOccurs="1" minOccurs="1"></element>
        </sequence>
    </complexType>
    <simpleType name="RLCDef">
        <restriction base="hexBinary">
            <minLength value="4"></minLength>
            <maxLength value="5"></maxLength>
        </restriction>
    </simpleType>
    <simpleType name="CityCodeDef">
        <restriction base="string">
            <length value="3"></length>
        </restriction>
    </simpleType>
    <simpleType name="OfficeCodeDef">
        <restriction base="string">
            <length value="6"></length>
        </restriction>
    </simpleType>
    <simpleType name="AgentCodeDef">
        <restriction base="string">
            <length value="9"></length>
        </restriction>
    </simpleType>
    <simpleType name="CarrierDef">
        <restriction base="string">
            <minLength value="2"></minLength>
            <maxLength value="3"></maxLength>
        </restriction>
    </simpleType>
    <simpleType name="FlightDef">
        <restriction base="string">
            <length value="6"></length>
        </restriction>
    </simpleType>
    <simpleType name="BookingClassDef">
        <restriction base="string">
            <length value="1"></length>
        </restriction>
    </simpleType>
    <simpleType name="StatusCodeDef">
        <restriction base="string">
            <length value="2"></length>
        </restriction>
    </simpleType>
    <complexType name="SegmentDef">
        <sequence>
            <element name="ElementID" type="int" maxOccurs="1" minOccurs="1"></element>
            <element name="ARNK" type="boolean" maxOccurs="1" minOccurs="1"></element>
            <element name="Carrier1" type="tns:CarrierDef" maxOccurs="1" minOccurs="1"></element>
            <element name="Carrier2" type="tns:CarrierDef" maxOccurs="1" minOccurs="1"></element>
            <element name="FlightNumber" type="tns:FlightDef" maxOccurs="1" minOccurs="1"></element>
            <element name="BookingClass" type="tns:BookingClassDef" maxOccurs="1" minOccurs="1"></element>
            <element name="Origin" type="tns:CityCodeDef" maxOccurs="1" minOccurs="1"></element>
            <element name="Destination" type="tns:CityCodeDef" maxOccurs="1" minOccurs="1"></element>
            <element name="DepartureTime" type="dateTime" maxOccurs="1" minOccurs="1"></element>
            <element name="ArrivalTime" type="dateTime" maxOccurs="1" minOccurs="1"></element>
            <element name="StatusCode" type="tns:StatusCodeDef" maxOccurs="1" minOccurs="1"></element>
        </sequence>
    </complexType>
    <complexType name="ResponsibilityDef">
        <sequence>
            <element name="BookingCity" type="string"></element>
            <element name="BookingOffice" type="string"></element>
            <element name="BookingAgent" type="string"></element>
            <element name="UpdateCity" type="string"></element>
            <element name="UpdateOffice" type="string"></element>
            <element name="UpdateAgent" type="string"></element>
            <element name="ResponsibleCity" type="string"></element>
            <element name="ResponsibleOffice" type="string"></element>
            <element name="ResponsibleAgent" type="string"></element>
        </sequence>
    </complexType>
    <complexType name="OSIDef">
        <sequence>

            <element name="CarrierCode" type="tns:CarrierDef"></element>
            <element name="Text" type="string"></element>
        </sequence>
        <attribute name="PassengerID" type="int"></attribute>

    </complexType>
    <complexType name="SSRDef">
        <sequence>

            <element name="CarrierCode" type="tns:CarrierDef"></element>
            <element name="SSRCode" type="string"></element>
            <element name="Text" type="string"></element>
        </sequence>
        <attribute name="PassengerID" type="int"></attribute>
        <attribute name="SegmentID" type="int"></attribute>
    </complexType>
    <complexType name="RemarkDef">
        <sequence>

            <element name="Text" type="string"></element>
        </sequence>
        <attribute name="PassengerID" type="int"></attribute>
    </complexType>
    <complexType name="TicketDef">
        <sequence>

            <element name="TicketNumber" type="string"></element>
            <element name="IssueAirline" type="tns:CarrierDef"></element>
            <element name="IssueOffice" type="tns:OfficeCodeDef"></element>
            <element name="IssueAgent" type="tns:AgentCodeDef"></element>
            <element name="IssueDate" type="dateTime"></element>
        </sequence>
        <attribute name="PassengerID" type="int"></attribute>
        <attribute name="SegmentID" type="int"></attribute>
    </complexType>
    <complexType name="PassengerDef">
        <sequence>
            <element name="PassengerID" type="int" maxOccurs="1" minOccurs="1"></element>
            <element name="PassengerName" type="string" maxOccurs="1"
                minOccurs="1">
            </element>
            <element name="Infant" type="boolean" maxOccurs="1" minOccurs="1"></element>
        </sequence>
    </complexType>
    <complexType name="ContactDef">
        <sequence>

            <element name="Type" type="string"></element>
            <element name="Text" type="string"></element>
        </sequence>
        <attribute name="PassengerID" type="int"></attribute>
    </complexType>
    <complexType name="PNRDef">
        <sequence>
            <element name="PnrInfo" type="tns:PnrInfoDef" minOccurs="1"
                maxOccurs="1">
            </element>
            <element name="Passenger" type="tns:PassengerDef"
                minOccurs="0" maxOccurs="unbounded">
            </element>
            <element name="Segment" type="tns:SegmentDef" minOccurs="0"
                maxOccurs="unbounded">
            </element>
            <element name="SSR" type="tns:SSRDef" minOccurs="0"
                maxOccurs="unbounded">
            </element>
            <element name="OSI" type="tns:OSIDef" minOccurs="0"
                maxOccurs="unbounded">
            </element>
            <element name="Ticket" type="tns:TicketDef" minOccurs="0"
                maxOccurs="unbounded">
            </element>
            <element name="Remark" type="tns:RemarkDef" minOccurs="0"
                maxOccurs="unbounded">
            </element>
            <element name="Responsibility" type="tns:ResponsibilityDef"
                minOccurs="1" maxOccurs="1">
            </element>
            <element name="Contact" type="tns:ContactDef" minOccurs="0"
                maxOccurs="unbounded">
            </element>
        </sequence>
    </complexType>
    <element name="PNR" type="tns:PNRDef"></element>
</schema>