I have something like this in an application:

User (1) -> (*) UserContact (1 to n User - > UserContact) and after that:
UserContact (1) -> (1) Contact ( 1 to 1 UserContact ->Contact ) where Contact is itself a User

the problem I have is this: When I remove a UserContact from the User's userContacts set, IT DOESN'T UPDATE the relationship in the db. It should remove the link from User to UserContact according to the hibernate docs. Also when I iterate over the userContacts collection and get an element from it and test userContacts.contains(an element from iterator) IT RETURNS FALSE. How can it not be here if I get it with the collection's iterator ? what am I missing here ?

Hibernate 2.1.1

- User mapping

<set
name="userContacts"
lazy="true"
inverse="true"
>
<key>
<column name="user_id" />
</key>
<one-to-many
class="com.ags.mobilechat.model.UserContact"
/>
</set>

- UserContact mapping

<many-to-one
name="contact"
class="com.ags.mobilechat.model.User"
>
<column name="contact_id" />
</many-to-one>

<many-to-one
name="user"
class="com.ags.mobilechat.model.User"
>
<column name="user_id" />
</many-to-one>

Here's the code:

try {
session = sessionFactory.getSession();
tx = session.beginTransaction();
result = callback.executeInSession(session);
tx.commit();
} catch (Exception e) {
.....
}

An I am implementing the callback.executeInSession for each transactional operation I need to perform

I tried also with cascade delete-orphan and all-delete-orphan. I doesn't remove the UserContact form user_contacts table

Read the Parent child relationship chapter and this one http://www.hibernate.org/155.html