Basic Usage
The examples below assume an SDO created with the schema
and instance information shown below, using the XML Data Access Service.
The instance document below describes a single company,
called 'MegaCorp', which contains a single department,
called 'Advanced Technologies'.
The Advanced Technologies department contains three employees.
The company employeeOfTheMonth is referencing the second employee,
'Jane Doe'.
<?xml version="1.0" encoding="UTF-8" ?>
<company xmlns="companyNS" name="MegaCorp"
employeeOfTheMonth="E0003">
<departments name="Advanced Technologies" location="NY" number="123">
<employees name="John Jones" SN="E0001"/>
<employees name="Jane Doe" SN="E0003"/>
<employees name="Al Smith" SN="E0004" manager="true"/>
</departments>
</company>
The root element of the schema is a company. The company contains departments, and
each department contains employees. Each element has a number of attributes to store
things like name, serial number, and so on. Finally, the company also has an IDREF
attribute which identifies one of the employees as the 'employeeOfTheMonth'.
<xsd:schema
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:sdo="commonj.sdo"
xmlns:sdoxml="commonj.sdo/xml"
xmlns:company="companyNS"
targetNamespace="companyNS">
<xsd:element name="company" type="company:CompanyType"/>
<xsd:complexType name="CompanyType">
<xsd:sequence>
<xsd:element name="departments" type="company:DepartmentType"
maxOccurs="unbounded"/>
</xsd:sequence>
<xsd:attribute name="name" type="xsd:string"/>
<xsd:attribute name="employeeOfTheMonth" type="xsd:IDREF"
sdoxml:propertyType="company:EmployeeType"/>
</xsd:complexType>
<xsd:complexType name="DepartmentType">
<xsd:sequence>
<xsd:element name="employees" type="company:EmployeeType"
maxOccurs="unbounded"/>
</xsd:sequence>
<xsd:attribute name="name" type="xsd:string"/>
<xsd:attribute name="location" type="xsd:string"/>
<xsd:attribute name="number" type="xsd:int"/>
</xsd:complexType>
<xsd:complexType name="EmployeeType">
<xsd:attribute name="name" type="xsd:string"/>
<xsd:attribute name="SN" type="xsd:ID"/>
<xsd:attribute name="manager" type="xsd:boolean"/>
</xsd:complexType>
</xsd:schema>
The XML Data Access Service maps the schema to an SDO. Attributes such as "name"
become primitive properties, the sequence of employees becomes a many-valued
containment relationship, and so on. Note that the containment relationships are
expressed as one complex type within another, whereas non-containment references are
expressed in terms of ID and IDREF, with a special
sdoxml:propertyType attribute specifying the type of the
non-containment reference.
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