Re: separation of church and state?

From: David Cressey <>
Date: Sat, 06 Oct 2007 19:07:38 GMT
Message-ID: <_1RNi.5958$gC2.2065_at_trndny09>

"paul c" <> wrote in message news:bhPNi.6572$_K.3238_at_pd7urf3no...
> David Cressey wrote:
> > "paul c" ...
> >
> > It is a little doctrinaire. Oracle/Rdb (originially DEC Rdb/VMS) has
> > always allowed ORDER BY in a view definition. No damage was done to the
> > ability of the user to apply concepts of relational algebra to the task
> > getting useful work done. One could reference such a view inside
> > view, or in any other context where an unordered table would have been
> > expected, and the results were logically equivalent to the result one
> > have obtained in the absence of the ORDER BY.
> >
> > Oracle RDBMS, by contrast, has always forbidden ORDER BY in view
> > definitions. Other than satisfying some people's need for doctrinaire
> > purity, the RDBMS users gained nothing by this restriction.
> >
> ...
> >
> > I think you're extrapolating Date's remarks to a point that he might not
> > agree with. A table with an index is still a table.
> >
> > BTW, the doctrinaire folks among us will insist that SQL does not have
> > in the standard. But we all know that SQL databases use indexes to
speed up
> > queries. And many application programmers appreciate being told what
> > indexes are present so that they can organize their queries for
> >
> > The doctrinaire people will say that the programmers have no need to
> > index information, because it's not part of the logical model. In
> > they are right. In practice, it helps to provide them with it.
> >
> >
> >
> I'm not sure it's a stretch. I feel fairly confident about resorting to
> the Information Principle when asking if a result is correct according
> to an algebra. Admittedly, I lump aspects such as ordering and indexing
> as 'not applicable' when trying to apply the IP. If I may be allowed to
> discount those aspects for results, I don't see why I can't discount,
> ie., ignore them, for intermediate results.

If I'm reading the above correctly, I think you and I are on the same page. Received on Sat Oct 06 2007 - 21:07:38 CEST

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