Hi,

It is possible to do that.I have an Furniture class which is a super class and chair and desk as the subclass and i am using table-per-inheritance as shown below

<class name="Furniture" table="FURNITURE_DETAILS" discriminator-value="F">
<id name="id" column="FUR_ID">
<generator class="increment" />
</id>
<discriminator column="type" length="1" />
<property name="materialUsed" length="20"/>

<subclass name="Desk" discriminator-value="D">
<property name="surfaceArea" />
<property name="width" />
</subclass>

<subclass name="Chair" discriminator-value="C">
<property name="noOfLegs" />
<property name="noOfHands" />
</subclass>

</class>

Now i need only the list of the chairs from this table then i do the following

Session session = sessionFactory.openSession();

Transaction tx = session.beginTransaction();

Query query=session.createQuery("from Chair");

List<Chair> chairlist =query.list();
System.out.println("The List size is "+chairlist.size());
for(int i=0;i<chairlist.size();i++)
{
Chair chair =chairlist.get(i);
System.out.println("No of Legs of Chair is ####### "+chair.getNoOfLegs());
}

tx.commit();

session.close();

It works.

kartik

Q1) will work fine.
In hibernate, If you query like Query query=session.createQuery("from java.lang.Object");

It will return all the objects that are persisted. You don't have to do anything specific to achieve this. Hibernate offers implicit polymorphism here.

Q2) second one won't work. Memo header is not Memo Details. But Memo details is a Memo header (the parent/child).
So when you query Memo Details [ i.e session.createQuery("from MemoDetails");], Hibernate will only look for MemoDetails[or its sub classes which you don't have any]

Hi,

The answer for your second Question.

I am sorry but in my case Char is a Furniture (parent/child)relationship and when i query for Chair("from Chair") i get the List<chair> only.

I hope this is what you are expecting.Retrieving collection of child elements.

Kartik