Re: Relation Definition

From: Jan Hidders <jan.hidders_at_REMOVETHIS.pandora.be>
Date: Wed, 23 Feb 2005 18:36:42 GMT
Message-ID: <_24Td.19245$Ix6.2454622@phobos.telenet-ops.be>

Anith Sen wrote:

>>> You defined them as pairs and in a set there can be two pairs
>>> with the same first component.

>
> Yes, and it was imprecise.

Good. That was my point, and I'm glad you agree now.

>>> It is not "an interpretation", it is the standard definition of a
>>> tuple as used by mathematicians.

>
> Are you contradicting your reference which blatantly states it as an
> interpretation?

Ah, my apologies. By "it" I meant the definition in the reference I gave.

> Even being a standard definition, its usage may not obviated in a
> relational definition. See, you stated the usage of n-dimensional
> notion as inappropriate while defining relations and some
> justification for that statement would be helpful.

Er, no, that's not exactly what I claimed. Here's what I really said:

Jan Hidders wrote:
> The notion of n-dimensional tuple is usually reserved for ordered
> tuples which is not appropriate here.

The "which" in that sentence refers to "ordered tuples" and not to "n-dimensional tuple". I have no problem with the usage of that term as long as it is explicitly stated that we are talking about unordered tuples and what those precisely are.

• Jan Hidders

Received on Wed Feb 23 2005 - 12:36:42 CST