<hibernate-mapping  package ="mypackage">	
    < class  name="MyClass" 	       
	       lazy="false" optimistic-lock="none"
       table="таблица_1_ключ">
        <id name="таблица_1_ключ" type="string" 
            column="" unsaved-value="null">
            <generator  class ="assigned"/>
        </id>             
        <property name="таблица_1_ключ" column="таблица_1_ключ"
        	not- null ="true" insert="false" update="false"/>        
        <bag name="таблица_2" lazy="true" cascade="none">
            <key>
        	 <column name="таблица_1_ключ"/>
            </key>
            <one-to-many  class ="MyClass2"/>
        </bag>
    </ class >
</hibernate-mapping>