Re: Object-relational impedence

From: David Cressey <cressey73_at_verizon.net>
Date: Tue, 04 Mar 2008 19:45:30 GMT
Message-ID: <uFhzj.2731$4D2.268_at_trndny06>


"Dmitry A. Kazakov" <mailbox_at_dmitry-kazakov.de> wrote in message news:4bza4t1lmhj9.1734ger7g3zac$.dlg_at_40tude.net...
> On Tue, 4 Mar 2008 15:41:40 +0000, Eric wrote:
>
> > On 2008-03-04, Dmitry A. Kazakov <mailbox_at_dmitry-kazakov.de> wrote:
> >> On Mon, 3 Mar 2008 23:03:41 +0000, Eric wrote:
> >>
> >>> No, RDBs partition data so that it is sensibly and easily available to
> >>> any possible application. So if you use OO you are saying "there will
> >>> never be any other application that will need my data".
> >>
> >> No, it is engineering which says so. It translates as "put the
requirements
> >> first," or simpler "pigs do not fly."
> >
> > So no-one ever says "we should be able to get that stuff out of the xyz
> > application and combine it with our data so that we can..."!
>
> You should plan this use case in advance. That would be a requirement. A
> system can only do things it was designed for. (This applies to RDBMS as
> well). For each application exist things it cannot do. That implies:
either
> A) there will never be any other application that will ask to do these, or
> B) the application is incorrect (= does not fulfill the requirements).
>

This is true for an RDBMS. But more to the point, can a relational (or SQL) database be designed in such a way that it has moderately good support for thousands of anticipated queries, of which only a few dozen will actually come to be used ? And will those few dozens of uses provide the appropriate payback on the investment in building the database?

Based on my experience with databases, I offer the firm opinion that the answer is yes. Received on Tue Mar 04 2008 - 20:45:30 CET

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