Re: Clean Object Class Design -- What is it?
From: Carl Rosenberger <carl_at_db4o.com>
Date: Sat, 21 Jul 2001 19:41:53 +0200
Message-ID: <9jcf1o$lkb$02$1_at_news.t-online.com>
Date: Sat, 21 Jul 2001 19:41:53 +0200
Message-ID: <9jcf1o$lkb$02$1_at_news.t-online.com>
Bob Badour wrote:
> >How is generating a key better than the ODBMS equivalent of a
> >system-generated Oid?
>
> The non-relational ODBMS always creates the OID and requires one to use
the
> OID
Implementations differ among object database systems.
Well-designed systems do not expose OIDs.
> The OID approach encourages designers to ignore other identifying
> attributes, which can sometimes lead to disastrous duplication.
Some object database systems keep track of all objects that are instantiated from storage. This safely prevents duplication and even allows automatic distinction between "new" and "update" calls.
How does your "mapping objects to columns" (domains) approach take care of object identity?
Kind regards,
Carl
--- Carl Rosenberger db4o - database for objects - http://www.db4o.comReceived on Sat Jul 21 2001 - 19:41:53 CEST