<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
   "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
   "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.dialog.listserv.model" >
  <class name="ItemGroup" lazy="false">
    <id name="id"><generator class="native"/></id>
      
    <property name="title" length="255">
      <column name="title" not-null="true" unique-key="BUSINESS_KEY"/>         
      <column name="title" not-null="true" unique-key="UNIQUE_TITLE_AT_LEVEL"/>
    </property>
      
    <property name="description" length="512"/>
    <property name="emailConfirmAtSubscrip" not-null="true"/>
    <property name="creationDate" update="false">
      <column name="creationDate" not-null="true" sql-type="TIMESTAMP" unique-key="BUSINESS_KEY"/>
    </property>
      
    <many-to-one name="parentItemGroup" cascade="none" fetch="join">
      <column name="PARENT_GROUP_ID" not-null="false" unique-key="UNIQUE_TITLE_AT_LEVEL"/>
    </many-to-one>

    <set    name="childItemGroups" cascade="all-delete-orphan" inverse="true" fetch="join">
      <key column="PARENT_GROUP_ID"/>
      <one-to-many class="ItemGroup"/>
    </set>

    <many-to-one name="publisher" class="Publisher"   update="false" cascade="none"   fetch="join">
      <column name="PUBLISHER_ID" not-null="true" unique-key="UNIQUE_TITLE_AT_LEVEL"/>
    </many-to-one>
   
    <set name="invitedForeigners" table="ACCOUNT_ITEMGROUP" fetch="join" cascade="save-update">
      <key column="GROUP_ID"/>
      <many-to-many class="Account" column="ACCOUNT_ID"/>
    </set>

    <set name="itemRefs" table="ITEMREF" cascade="all-delete-orphan" fetch="join" outer-join="false" >
      <key column="GROUP_ID"/>
      <one-to-many class="ItemRef"/>
    </set>
    <property name="availableForSubscribers" not-null="true"/>      
  </class>   
</hibernate-mapping>

....
return (ItemGroup) session.get(ItemGroup.class, itemId, LockMode.UPGRADE);
....

...
      <set    name="itemGroups"
            cascade="all-delete-orphan"
            inverse="true"
            where="PARENT_GROUP_ID is null"
            fetch="select"
            >
         <key>
            <column name="PUBLISHER_ID" not-null="true"/>
         </key>
         <one-to-many class="ItemGroup"/>
      </set>

...