Re: just passed 1st exam- projections???

From: Jim Lyons <jlyons_at_weblyons.com>
Date: 8 Jun 2001 14:37:33 -0700
Message-ID: <e67857c9.0106081337.612c8de5@posting.google.com>

"Daniel A. Morgan" <dmorgan_at_exesolutions.com> wrote in message news:<3B182DA2.D5129D77_at_exesolutions.com>...
> samy atoui wrote:
>
> > Thank's a lot, I've never heard this term...
> > Manuela
> > > a projection is any select returning not all the attributes/columns of a
> > > table.
> > >
> > > Hth,
> > > Sybrand Bakker, Oracle DBA
>
> Don't dispair. I've been doing this since 1969 and I hadn't a clue either.
>
> Daniel A. Morgan

I ran across this term, I believe in Date's book, a long time ago, 15 years or
so. Soon after that I began learning SQL. There is (or was) a sort of
generic vocabulary used in the study of the theory of relational databases and it was different from SQL. To 'project' in the general theory essentially
meant the same as 'select' in SQL. A 'select' clause in the general theory
was essentially the same as the 'where' clause in SQL. I remember being
struck by the different use of the word 'select'.

I guess SQL has become such a standard that the old terminology is getting
lost. Received on Fri Jun 08 2001 - 16:37:33 CDT