Re: What is a tuple?

From: Martijn van Oosterhout <kleptog(at)svana(dot)org>
To: David Siebert <dsiebert(at)eclipsecat(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: What is a tuple?
Date: 2002-06-27 14:30:56
Message-ID: 20020628003056.A12854@svana.org
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On Thu, Jun 27, 2002 at 09:17:22AM -0400, David Siebert wrote:
> Tuple = row... Why not just use row? I know what a tuple is but it seems
> like a word to impress more than inform.

I can think of a few reasons:

1. Databases have been using the term "tuple" for a very long time.
Relational algebra talks about tuples exclusively.
2. The definition of a "tuple" is precise (a set of elements). A "row" could be anything
(row in array, row on screen).
3. Whats wrong with having multiple words for the same thing anyway?

There's also:

relation == table
resultset == tuples (?)

Anyway, have a nice day :)

> -----Original Message-----
> From: pgsql-general-owner(at)postgresql(dot)org
> [mailto:pgsql-general-owner(at)postgresql(dot)org]On Behalf Of Martijn van
> Oosterhout
> Sent: Tuesday, June 25, 2002 10:54 PM
> To: Elaine Lindelef
> Cc: pgsql-general(at)postgresql(dot)org
> Subject: Re: [GENERAL] What is a tuple?
>
>
> On Tue, Jun 25, 2002 at 02:40:03PM -0700, Elaine Lindelef wrote:
> > My apologies for the stupid question, but before I started using
> > postgres I never came across the word "tuple" quite in this context
> > before. I know a "tuple" as "a data object containing two or more
> > components" ... but I'm not sure of its precise meaning in the
> > postgres universe. Is a tuple a row, a field value, a field value
> > paired with its datatype, what? If someone asks me the size of my
> > largest tuple, how do I calculate it? It seems to be related deeply
> > to the structure of postgres somehow.
>
> A tuple is a row. Isn't this in the glossary somewhere?
> --
> Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> > There are 10 kinds of people in the world, those that can do binary
> > arithmetic and those that can't.
>
>
>
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>

--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> There are 10 kinds of people in the world, those that can do binary
> arithmetic and those that can't.

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