We have a Unit object (military Unit that represents the army hierarchy - e.g. Division is a Unit; a Division can contain a Brigade which is a Unit). We use a single table, tblUnit, with a parentUnitID (foreign key to the same table). The parentUnitID can be null. How is this modeled in hibernate/nHibernate?

Note that we also have a Unit object hierachy with different types of Units persisted using the single table, tblUnit (table-per-class-hierarchy); this means we want both relationships.

Thanks,
Bill

Have you tried mapping it just as you say? The Unit has a Parent Unit property which references the Unit, and then the Unit also has a ChildrenUnits collection which references the units that point to this unit as it's parent? I hope that isn't too confusing.

I believe that mapping should work fine. Did you run in to issues when you tried it? We've done hierarchies before, but it was always through a join table (many-to-many relationships).

Thanks -- yes, it does work.