Re: Define "flatten database" ?

From: Mark Johnson <102334.12_at_compuserve.com>
Date: Sat, 25 Feb 2006 12:05:43 -0800
Message-ID: <hjd1021r1i12pggg356d78t16f2g2a7rb7_at_4ax.com>


"David Cressey" <dcressey_at_verizon.net> wrote:

>define a "relational table" as the representation of a relation in a relational database.
>Describe an "SQL table" as an approximation to a relational table. Move on
>from there.

That paper of Codd's that I quoted in a couple of messages showed his desire to even replace the idea of the table/relation correspondence with that of a table/relationship. If the tuples were not always in order, as they are in picking elements from successive sets in the theory, then he perhaps felt uncomfortable still terming a table based on that, a relation. Thus, terminology. Once you move from the theory to the implementation, everything else can change, as well. And as things are changed on the working side of it, perhaps the connection with the theory grows more tenuous. If that poses problems, then that can be stated. If it both solves and causes problems, so too. Of that, the use of self-referential tables is pretty much the example of the moment, and such use of Connect By, or similar. Received on Sat Feb 25 2006 - 21:05:43 CET

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