Hi,
I have problem with classes inheritance. I have table Register. Sometimes I don't need all it's columns, so I decided to map this table twice. I've created class
RegisterBasic {

RegisterBasic(){}

protected int registerNumber;
protected UserBasic owner;

public int getRegisterNumber() {
return registerNumber;
}

public void setRegisterNumber(int registerNumber) {
this.registerNumber = registerNumber;
}

public UserBasic getOwner() {
return owner;
}

public void setOwner(UserBasic owner) {
this.owner=(UserBasic)owner.clone();
}


}

And it's mapinig document looks like this:

<hibernate-mapping>
<class name="connections.register.RegisterBasic" table="REGISTER">
<id name="registerNumber" column="REGISTER_NUM" type="integer">
<generator class="assigned"/>
</id>
<many-to-one name="owner" column="USER_ID" class="connections.user.UserBasic" not-null="true" foreign-key="FK_REG_USER"/>
</class>
</hibernate-mapping>

And than, it's classes extention:

class Register extends RegisterBasic{

Register(){}
private UnitClass unitClass;
public UnitClass getUnitClass() {
return unitClass;
}

public void setUnitClass(UnitClass unitClass) {
this.unitClass=(UnitClass)unitClass.clone();
}

And it's mapping:
}

<hibernate-mapping>
<joined-subclass name="connections.register.Register" extends="connections.register.RegisterBasic">
<key column="registerNumber"/>
<many-to-one name="unitClass" column="UNIT_CLASS" class="connections.fund.UnitClass" not-null="true" foreign-key="FK_REG_UNIT"/>
</joined-subclass>
</hibernate-mapping>


When I haven't used extention and just define again all variables and their functions again in class Register and in iRegister.hbm.xml file everything worked fine. But when I use this notation query
Query q = getSession().createQuery(" from Register " );
List result =q.list()
returns empty list. I really don't understand this. What is wrong with this notation?

Nobody used Hibernate to class which is an extention of another class? I would appreciate any help or advice.