Hi, It sounds like you're looking for OpenJPA's constant join behavior. You can read about it at http://openjpa.apache.org/docs/nightly/manual/manual.html#ref_guide_mapping_notes_nonstdjoins
-Patrick On 8/21/07, Nat Gross <[EMAIL PROTECTED]> wrote: > [In an existing ejb 2 application] I have an interesting manytomany > scenario. > > Class EntityA with a 1 field Integer pk can relate to other instances of > itself in more than one way. > Not only can it have many EntityA children and have many EntityA parents it > can have the SAME EntityA Parent/Child more than once. > Each EntityA needs a reason as to why it relates to the other EntityA. > (Suppose EntityA is a Person that can relate to another Person in more than > one way, say a cousin, a spouse, employer, business partner. [ahem<g>]) > Currently I have a table, ARELATIONS, with three Integer fields: srcPK, > targetPK, relateType. All three fields make up the PK. Currently I am > manually controlling the joins of this table with EntityA. I would like to > utilize jpa to do this. > > Also important to note is that it is not enough for the end-user to simply > fetch related EntityA records, the *reason* (relateType) is also important. > > Basically I should be able to define two OneToMany Unidirectional > Collection<Arelations> fields in EntityA, but whatever I try with Toplink I > get different problems. (Basically, Toplink wants yet another intersection > table, which I don't want.) > I hope openjpa has a better solution. > Please adivse. > > Thanks > natG > -- Patrick Linskey 202 669 5907
