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<?xml version="1.0" encoding="ISO-8859-1"?>
<refentry id="MS-A-3b">
  <refmeta>
    <refentrytitle>Using Annotated XSD Schemas for Creating XML Views</refentrytitle>
    <refmiscinfo>tutorial</refmiscinfo>
  </refmeta>
  <refnamediv>
    <refname></refname>
    <refpurpose>Using sql:relationship to Specify Relationship on multiple elements.</refpurpose>
  </refnamediv>

<refsect1 id="MS-A-3ba">
<title>Example. Specifying sql:relationship on multiple elements.</title>
<para>
In this example, the annotated XSD schema contains the &apos;Customer&apos;, &apos;Order&apos;, and &apos;OD&apos; 
elements. The &apos;Order&apos; element is a subelement of the &apos;Customer&apos; element. &lt;sql:relationship&gt; 
is specified on the &apos;Order&apos; subelement; therefore, orders that belong to a customer appear as subelements 
of &apos;Customer&apos;.
The &apos;Order&apos; element includes the &apos;OD&apos; subelement. &apos;sql:relationship&apos; is specified 
on &apos;OD&apos; subelement, 
so the order details that pertain to an order appear as subelements of that &apos;Order&apos; element.
</para>
<programlisting><![CDATA[
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
            xmlns:sql="urn:schemas-microsoft-com:mapping-schema">
<xsd:annotation>
  <xsd:appinfo>
    <sql:relationship name="CustOrders"
        parent="Demo.demo.Customers"
        parent-key="CustomerID"
        child="Demo.demo.Orders"
        child-key="CustomerID" />

    <sql:relationship name="OrderOrderDetail"
        parent="Demo.demo.Orders"
        parent-key="OrderID"
        child="Demo.demo.Order_Details"
        child-key="OrderID" />
  </xsd:appinfo>
</xsd:annotation>

  <xsd:element name="Customer" sql:relation="Demo.demo.Customers" >
   <xsd:complexType>
     <xsd:sequence>
        <xsd:element name="Order" sql:relation="Demo.demo.Orders"  
              sql:relationship="CustOrders" maxOccurs="unbounded" >
          <xsd:complexType>
              <xsd:sequence>
                <xsd:element name="OrderDetail" 
                             sql:relation="Demo.demo.Order_Details" 
                             sql:relationship="OrderOrderDetail" 
                             maxOccurs="unbounded" >
                  <xsd:complexType>
                    <xsd:attribute name="OrderID" type="xsd:integer" />
                    <xsd:attribute name="ProductID" type="xsd:string" />
                    <xsd:attribute name="Quantity" type="xsd:integer" />
                  </xsd:complexType>
                </xsd:element>
              </xsd:sequence>
              <xsd:attribute name="OrderID" type="xsd:integer" />
              <xsd:attribute name="CustomerID" type="xsd:string" />
          </xsd:complexType>
        </xsd:element>
      </xsd:sequence>
      <xsd:attribute name="CustomerID" type="xsd:string" />
     </xsd:complexType>
  </xsd:element>
</xsd:schema>
]]></programlisting>
<para>Let the schema is written to the file &apos;Cust_Order_OD.xsd&apos;, then after loading this file by 
<function>xml_load_mapping_schema_decl</function> function, the first example will produce a result for the XPath query:
</para>
<programlisting><![CDATA[
XPATH [__view 'Cust_Order_OD'] /Customer[@CustomerID="QUEEN"];
]]></programlisting>
<para>
the second example will produce a result for the XQuery query:
</para>
<programlisting><![CDATA[
select xquery_eval('<doc>{for $r in xmlview("Cust_Order_OD")/*[@CustomerID="QUEEN"] return $r}</doc>', xtree_doc('<q/>'))
]]></programlisting>

</refsect1>
</refentry>
