anonymous wrote : Sorry, but your ERM does not make any sense. What are you trying to achieve? The example is a bit contrived; I was simply modeling a Department table that has an association to a DeparmentStrings table which stores a localized name of the department, i.e. the composite key of DeparmentStrings would be (department_id, lang_code) where lang_code is something like "en-us". I'm really looking for any example where the owning field of a ManyToOne relationship is also part of a composite key (via either IdClass or EmbeddedId.) View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4037708#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...