Re: c.d.theory glossary (repost)
Date: Thu, 13 May 2004 17:14:28 -0700
Message-ID: <l338a0tlq4mrsdi31bg2tfbg1sdbn1ch5h_at_4ax.com>
mAsterdam <mAsterdam_at_vrijdag.org> wrote:
>Eric Kaun wrote:
It would help if it were more plainly written. I have been using
databases for quite a while, but I would like to learn more theory.
Some of the definitions here are rather obtuse. Examples follow:
[snip]
>[Class]
>
>...
>> Ugh, can't find it - gone from my newsgroups.
>
>--------------- Do I contradict myself?
>Glossary 0.0.2: Very well then I contradict myself;
>may 5, 2004 I am large, I contain multitudes.
>--------------- -- Walt Whitman
>
>Preamble:
>---------------
>This glossary seeks to limit lengthy misunderstandings in
>comp.database.theory.
>A class is what provides a name and a place for
>the abstract behavior of a set of objects
>said to belong to the class. (Larry Wall, Apocalypse 12)
I am glad that I already know what a class is.
[snip]
>[Domain]
>Given a relation R, a domain is a set Sn such that for each tuple (A1,
>A2, ...An, ...Am) in R, An is an element of Sn.
Huh?
[snip]
>[NULL]
>The insanity bit. No! The humility marker.
>mu: The absence of an answer to a question which requires an answer.
Cute, but not of much practical help.
[snip]
>[Relation]
>A relation is a subset of the set of ordered tuples (A1, A2, ... Am)
>formed by the Cartesian cross-product of sets S1 x ... x Sm where each
>An is an element of Sn.
Huh?
[snip]
Sincerely,
Gene Wirchenko
Computerese Irregular Verb Conjugation:
I have preferences. You have biases. He/She has prejudices.Received on Fri May 14 2004 - 02:14:28 CEST