Hibernate version: 3.0

Just a simple question. I'd like to delete a parent entity together with its child records. The cascade property in the entity hbm file is set to "all-delete-orphan".

When I use
session.delete(session.load(entity.getClass(), entity.getId()));
everything works fine and child records are deleted.

But my motivation is to be able to delete the whole thing without loading the entity. The following code
session.createQuery("delete Entity where id = 1").executeUpdate();
throws a "child record found" exception.

What can the problem be? Please your advice. Thanks a lot in advance.
L G

We moved to v3.1 and the problem remains. Or am I missing smth here?

IMHO, you're bypassing Hibernate by using a delete query. This way, you're on your own.

If you want Hibernate to take care of the relationships, I don't think you've got any way around loading the objects. But you probably don't have to load the objects in the collection as well, I think, the proxies will do just fine.

In hibernate3 the team decided to follow the ejb3 spec and change the function of session.delete around entirely. It will only delete the object and all its children if EVERYTHING about an entity and its children is already loaded into memory from the database. This is to avoid performance problems involved with what you explained, loading everything into memory to then just delete it all.

The best way to do it now (performance wise) is to run

queries with some custom written hql delete queries.

I wouldn't worry too much about loading the entity and then calling delete on it. If you have most of your properties and associations set to load lazy and/or by proxy, the processing hit should be minimal. If you turn on debug logging for the org.hibernate.sql package (at least, possibly more if you want), you should be able to see how much is actually getting loaded prior to the delete statement. You can tune your lazy/proxy settings from there.

Otherwise, multiple HQL statements will work, but you aren't taking advantage of the cascade settings then.

e

Hi,

Thanks for the answer.

But... session.update(String hql) - there is no such API...

you might like this upcomming feature
http://opensource2.atlassian.com/projec ... se/HHH-695

oh, and session.createQuery("delete ...").executeUpdate() is what i meant to type instead of session.update("delete... ).executeUpdate()

Great, thanks