Re: Design question

From: Robert Klemme (bob.news_at_gmx.net)
Date: 07/31/04 

Date: Sat, 31 Jul 2004 12:59:52 +0200

"Mike" <decxor1@hotmail.com> schrieb im Newsbeitrag
news:87a6660f.0407301022.151d478f@posting.google.com...
> > >
> > > I was thinking of having a configuration file that maps object IDs to
> > > database table(since the DB objects essentially represent the database
> > > table entities).
> >
> > IMHO that's a bad idea since you need to keep this data redundant - it's
> > in the mapping file as well as in the database.
> >
>
> If I do not have a configuration "mapping" file, how will I associate
> a DB table to an object. WHat would be a good design pattern(if any)
> to let a broker object determine DB mappings based on the request by a
> entity object.

You only need to map types to tables, not individual ids to instances. You
could even have a central table that holds [id, type, table]

But as I said, there's plenty of OR mapping tools around - partly free.

Regards

    robert

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