hi,
I posted my query here with no response: http://forum.hibernate.org/viewtopic.php?t=958559 . So reposting..

Basically if I make many-to-one from Class1 to Class2 without one-to-many from Class2 to Class1, I am not able to delete Class2.

If I try delete Class2, it throws ConstraintViolationException if any row in Class1 is already pointing to Class2. Class2 is used to represent some configuration data. Class1 is runtime data which points to configuration data. But I need to delete Class2 at some point. I can use not-found="ignore" to ignore exception while retrieving Class1 and it points to invalid row of Class2.


How is this solved?

Thanks,
Hari Sujathan,
Pune, India

You need to ensure that you don't have inverse="true" on, and include cascade="delete" or something that includes delete cascades.

many-to-one doesn't allow any inverse attribute. I am not using any one-to-many/many-to-many.

Thanks,
Hari

Can I say in hbm2ddl that not to generate constraint for this many-to-on relation?

Thx,
Hari.

Hi,

Have you tried to deassociate the Class2 from Class1 before deleting the Class2 instance.
Something like:
instanceOfClass1.setClass2(null).

But this mean that you have to permit null into the column that represent the foreign key for Class2 table.

I hope that help

Calin

I don't think so. Besides, you almost certainly don't want to do this. You shouldn't just delete something that other things have a reference to. Calin's suggestion is the usual solution, but alternatives are possible. For example, you could use a link table, and make the mapping a many-to-many unique="true" (thus making it effectively a many-to-one mapping): you can set up that mappnig so that deleting either side of the association deletes any entries in the link table but not the object on the other side of the association. This solution is described in the ref docs, sections 7.3.1 and 7.3.2 (not that there's a typo in some older revisions of that doc: replace <join>s with <set>).