Re: What is a "tuple"

On Fri, Jun 22, 2001 at 06:31:03PM +0200, Kristoff Bonne wrote:
> Greetings, (and also Alex)
> 
> On Fri, 22 Jun 2001, Josh Berkus wrote:
> > > Excuse my lack my 'database'-jargon, but what is a 'tuple'?
> 
> > Also known as a "Record", or a "Row".  The word "tuple" is used because
> > it can refer to a row returned as part of a result set as well as a
> > record in a table.  Strictly speaking, a row returned from most queries
> > is not a record, as that row does not exist in permanent storage
> > anywhere .... it is created by the query.  Hence, "tuple".

It's probably a back formation from the suffix 'tuple' as in the sequence:

single, double, triple, quadruple, quintuple, sextuple, septuple, ...

So, mathematicians generalized this (as is their wont) to 

[algebraic expression]-tuple, such as:
       n-tuple, (n^2)-tuple

Which found their way to The Relational Algebra, simplified to just
'tuple' and hence, to SQL.

Ross (way to much detail!) Reedstrom