Re: Transitive Closure
Date: Tue, 18 May 2004 10:41:40 -0700
Message-ID: <64sqc.31$ST6.81_at_news.oracle.com>
"x" <x-false_at_yahoo.com> wrote in message news:40a9f72d$1_at_post.usenet.com...
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> "Alfredo Novoa" <alfredo_at_ncs.es> wrote in message
> news:e4330f45.0405180244.9d5d351_at_posting.google.com...
> > mikharakiri_nospaum_at_yahoo.com (Mikito Harakiri) wrote in message
> news:<8a529bb.0405171058.36a5a26_at_posting.google.com>...
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> > > So we are talking about different algebra, that has a universe with
> > > elements being unary relational algebra operators only -- selection,
> > > projection,
> >
> > They ARE binary operators. Restriction has two operands: a relation
> > and a boolean function, and projection a relation and a set of
> > attributes.
>
> I think "they are" is too strong. I'd suggest "they may be regarded as".
"May" in the same sence as multiplication of vector by scalar can be regardered as binary operation in Linear Algebra. The question is you get any insight from such perspective. Received on Tue May 18 2004 - 19:41:40 CEST