Hi All,

I am using Hibernate3.2.3. I am facing problem while deleting an object which is having composite key. When I call session.delete(object) method with with wrong set of composite key( it means that composite key is not in the database) I dont get any exception. Unless and untill I dont get exception I wont be able to know whether my deletion was successful or not. If I pass correct composite key, things happen normally and that row is getting deleting. Below is my code.

public boolean deleteUser(AppUserProfile user) throws Exception{
try{
session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
sysLog.info("About to delete a user with User Name: "+user.getUserName());
session.delete(user);
session.flush();
session.getTransaction().commit();
return true; // means delete successfull
}catch (Exception e) {
session.getTransaction().rollback();
sysLog.finer(e.getMessage());
throw e;
}
}

Can anyone tell me y is it happening? When I tried doing samething with single primary key, I got exception, so in this it is working in expected way.

It appears you're trying to delete a transient object i.e. not associated with the current session. If you made it managed first by calling merge(user) you'll get an exception when the user has already been deleted.

The difference in handling between a single id (e.g. a Long) and a composite id results from the inability to define a "not-saved" value for the composite.

Hibernate can be sure that an object with a Long id that isn't null (i.e. Long's not-saved value) is a transient object. As such it tries to delete it and fails - you get an exception.

With the composite id its not so clear. It could equally be a transient or a new, unsaved object. To decide which, hibernate attempts to load the object from the cache, then the database. This returns nothing in your case because its already deleted so hibernate assumes its a new object and silently discards it (as it should for a new object).

Why don't you just switch to Long as a surrogate primary key?