For example, consider the following item descriptors, which define an author repository item type and an address repository item type. The address property of the author repository item type has the attribute item-type="address", indicating that the value of the address of an author is a repository item of type address. The address property has the attribute cascade="insert,update,delete"; as a result, whenever an author type repository item is created, added, updated, or deleted, the corresponding address repository item is also.

<!-- The "author" item type -->
<item-descriptor name="author">
  <table name="author" id-column-names="author_id" type="primary">
    <property name="name"/>
    <property name="address" item-type="address" cascade="insert,update,delete"/>

<!-- The "address" item type -->
<item-descriptor name="address">
  <table name="address" id-column-names="address_id" type="primary">
    <property name="streetAddress"/>
    <property name="city"/>
    <property name="state"/>
    <property name="zip"/>
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