Re: Oracle, Objects and Relational Model

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As far as I know the OTT (Oracle Type Translator) creates only C-headers with structures using ORACLE data types. There is no language binding. Once you have successfully retrieved your objects from the database, the tough work begins with filling your objects (e.g. C++ objects) with data from ORACLE objects, since it is nearly impossible to work with ORACLE types (even to multiply two numbers you need an OCI call). The OCI (Oracle Calling Interface) consists of C-Functions with lots of parameters. To say nothing of changing your schema...

wolfgangwkeller_at_my-deja.com wrote:
>
> In article <383E3E22.1B0F2800_at_gmv.es>,
> Adolfo =?iso-8859-1?Q?S=E1nchez?= <adfsanchez_at_gmv.es> wrote:
>
> this question is somewhat tough as you might see from the number of
> answers so far .
>
> There is plenty of experience with O/R mapping tools for conventional
> RDBMS (without the OR extensions) as you can see if you have a
> look at
> http://www.cetus-links.org/oo_db_systems_3.html
>
> There are also plenty of patterns that you will find in most of the
> products ... see
> http://www.objectarchitects.de/ObjectArchitects/orpatterns/index.htm
>
> We can expect that an access layer on top of an OR DB will look very
> similar to the ones on Rel DBs except that some mapping features
> like e.g. for inheritance will not be needed.
> I take my confidence from the fact that the patterns behind
> O/R mappers and OODBs are identical to a great extent - and a good
> O/R mapper has an architecture somewhat near to an OODB - except
> for the storage management
>
> But again - your question is tough as I have not yet seen a product
> or a product solution that uses the OR database extensions
>
> So my suggestion would be...
> * if you want a quick solution - take one of the O/R mapping tools
> that are commercially available
> * if you have time, want to do an innovative project - try to build
> your own on top of an OR database
>
> If I'm wrong and somebody else has information on access layers
> on top of OR extended databases, I'd be glad to har about that and
> check it out, as I'm interested in anything on persistence
>
> Hope that helps
>
> Wolfgang
>
> http://www.objectarchitects.de/ObjectArchitects/
> > Hello,
> >
> > I have to store objects (its attributes) in Oracle and I'm considering
> > two options:
> >
> > First one: storing mapping attributes to columns and objects to rows,
> > that is,applying translation from the Object Oriented Paradigm to the
> > Relational Model Paradigm and using tables, records, foreign keys...
> >
> > Second: storing them as objects using the Object Type provided by
> Oracle
> > 8 and the OTT (Object Type Translator) tool.
> >
> > Which is the best?, Have you got any experience with OTT?, What do you
> > recommend to me?
> >
> > Thanks,
> >
> > Adolfo.
> > --
> > ____________________________________________________________________
> > Adolfo Sánchez Domínguez GMV, S.A. Grupo de Mecánica de Vuelo
> > mailto:adfsanchez_at_gmv.es Sector Foresta,1. TRES CANTOS
> > PHO: +34 91 806 4443 E-28760 MADRID (SPAIN)
> > FAX: +34 91 806 4641 http://www.gmv.es
> >
> >
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.

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--------------38509B0F7DFA3B370B4F64F8-- Received on Mon Dec 06 1999 - 21:10:10 CET