Hi,

I'm having a lot of trouble figuring out the mapping needed for this setup. I've looked through FAQs, tutorials, and searched the forums with no luck (although I wouldn't be surprised if a similar issue has already been answered).

Basically, what I want is a many-to-many relationship where the association table stores additional information (e.g. Is_Historical, below).


Here's the setup:
desired SQL tables:

Feature (table)
----------
Feature_ID (PK) int
...
...


FeaturePlaceName (table)
----------
Feature_ID (FK) int
PlaceName_ID (FK) int
Is_Historical


PlaceName (table)
----------
PlaceName_ID (PK) int
PlaceName (Unique) string


desired Java classes (only two). The Feature.Set<PlaceName> represents the many-to-many, but the individual field PlaceName._isHistorical is stored in the association table.

Feature (class)
----------
int _id
Set<PlaceName> _names
...


PlaceName (class)
----------
int _id
String name
boolean _isHistorical
...


Any help or links to similar issues would be appreciated! Thanks!!

Dave

Well, I think I just stumbled across something that is working, but it may not be the prettiest way. It also doesn't have all of the PK compositions that I'd like.

I had to add an extra class (Name.java) just to wrap a String in order to map it to its own table.

The remaining problem is that the FeaturePlaceName table doesn't have the composite PK of Feature_ID (FK) and Name_ID (FK) that I'd like. Any idea how I can accomplish this?

Mappings:


Thanks again!
Dave

Well, I think I finally answered my own question. The above guess is somewhat incorrect.

The answer that I needed and was digging for is provided in the Hibernate "Example: Various Mappings" for Customer/Order/Product. I just hadn't used the right combination of terms when searching.

http://www.hibernate.org/hib_docs/refer ... derproduct

Hope this is helpful to anyone else with a similar problem!