On entity bean primary keys... no matter if you're talking about entity beans or relational databases in general it is always a good idea to use primary keys without business meaning. You might run into a problem later if your PK embodies a business concept and this concept changes later in the lifecycle of your software product. So using a PK that does not have any business meaning whatsover is generally considered a good idea in software development. Using autonumber fields is generally a convenience issue as most DB's support this directly and it's also easy to implement yourself if you want to remain db independent.
Apart, requirements might be that you're PK is globally unique. This is the case in my situation and that's why I'm using the UUID for EJB pattern which generates a 32-bit PK w/o database which is unique across space and time (see www.theserverside.com, Patterns section rsp. EJB Design Patterns book) for more info. cu, Bernie -----Ursprungliche Nachricht----- Von: Ingo Bruell [mailto:[EMAIL PROTECTED]] Gesendet: Montag, 29. April 2002 10:33 An: [EMAIL PROTECTED] Betreff: Re[2]: [Xdoclet-user] value-objects wrong PK usage Hi, oops, my reply was going directly to Marius. MK> Alex Loubyansky wrote: >> What do you mean "complex PKs don't work very well with jboss3.x now"? >> MK> http://main.jboss.org/forums/thread.jsp?forum=46&thread=9931 MK> So i stopped using it. I don't know if it is just the table-creating MK> problem. I read your article and it sounds that jboss has only problems to create the foreign key constraints, right ? I am not using foreign keys in the db yet, so i have not this problem. But i wonder why most the time autonumber fields are used as pk. Could someone explane (it should be OT but i am interested in) so long Ingo Bruell --- <[EMAIL PROTECTED]> <[EMAIL PROTECTED]> <ICQ# 40377720> Oldenburg PGP-Fingerprint: CB01 AE12 B359 87C4 BF1C 953C 8FE7 C648 169E E5FC Germany PGP-Public-Key available at pgpkeys.mit.edu _______________________________________________ Xdoclet-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/xdoclet-user _______________________________________________ Xdoclet-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/xdoclet-user
