I have class Country that has bidirectional one-to-one ("0..1 to 0..1" to be specific) association to itself. One end of the association has name 'nextCountry', another is called 'previousCountry'.

To persist the class I use the following mapping:
<hibernate-mapping default-cascade="none">
<class name="model.CountryImpl" table="COUNTRY" dynamic-insert="false" dynamic-update="false">
<id name="id" type="java.lang.Integer" unsaved-value="null">
<column name="ID" sql-type="INTEGER"/>
<generator class="native">
</generator>
</id>
<property name="name" type="java.lang.String">
<column name="NAME" not-null="true" unique="true" sql-type="VARCHAR(255) BINARY"/>
</property>
<property name="active" type="boolean">
<column name="ACTIVE" not-null="true" unique="false" sql-type="TINYINT"/>
</property>
<many-to-one name="nextCountry" class="model.CountryImpl" foreign-key="COUNTRY_NEXT_COUNTRY_FKC" cascade="none" lazy="proxy" fetch="select">
<column name="NEXT_COUNTRY_FK" not-null="false" sql-type="INTEGER" unique="true"/>
</many-to-one>
<one-to-one name="previousCountry" class="model.CountryImpl" property-ref="nextCountry" cascade="none" lazy="proxy" fetch="select"/>
</class>
</hibernate-mapping>

Everything works great - I can persist the class. But there is one problem. Let's say that there is the following state in the database:

USA -> France -> Holland -> Poland (four Country objects are persisted in the database: USA, France, Holland, Poland, and USA's 'nextCountry' field points to France, France's 'nextCountry' field points to Holland, Holland's 'nextCountry' field points to Poland).

Unfortunately when I load USA object, hibernate loads USA and all the objects that are referenced from USA (in this case it means that all the objects are loaded). Because I have specified lazy="proxy" for 'nextCountry' field in the above mapping, I would expect that when I request USA i will get only USA object with its 'nextCountry' field initialized by proxy of France, whithout a database hit to fetch France object.

Could you tell me what's going on and how to get the behavior that I expect? I use hibernate 3.1.3

Thank you for your help,

Lukasz Indyk.

Hi,

quickly checked your mapping. Are you sure you are not missing something in it?
The table field is not declared....



rgds