Re: A Normalization Question

From: Paul <paul_at_test.com>
Date: Thu, 08 Jul 2004 09:48:14 +0100
Message-ID: <GS7Hc.4295$Fc7.790377@stones.force9.net>

Neo wrote:

>>You'll have to explain why storing "brown" three times is redundant, 
>>while storing ->5 three times is okay.

>
> With respect to dbs, normalization is the process of eliminating or
> replacing duplicate things with a reference to the original thing
> being represented. Within the context of a db, duplicate references
> are not considered redundant because they are unrelated to the thing
> being represented.

You could say that the string "brown" is a reference to the actual colour brown. Or the string "Brown" is a reference to the surname Brown.

This is where the database's knowledge ends and the human mind begins; the jump from syntax to semantics.

Redundancy in terms of databases is about removing semantic duplicates, not about removing syntactic duplicates. i.e. about the logical level, not the physical level.

I think the type of redundancy you're talking about is more lower-level like information theory, Huffman coding etc.: http://en.wikipedia.org/wiki/Information_theory

It sounds like you're trying to roll these two concepts into one when it's more powerful and useful to have them separate.

Paul. Received on Thu Jul 08 2004 - 03:48:14 CDT