Re: object algebra

From: Chris Hoess <choess_at_stwing.upenn.edu>
Date: Thu, 4 Mar 2004 05:03:19 +0000 (UTC)
Message-ID: <slrnc4de4m.i49.choess_at_force.stwing.upenn.edu>

In article <4b45d3ad.0403031714.59dd6db1_at_posting.google.com>, Neo wrote:

>> You're joking, right? Please tell me you're joking.

>
> No, not joking. See www.xdb1.com/Basic/Symbol.asp,
> www.xdb1.com/GUI/Labels.asp and www.xdb1.com/HowTo/Find.asp

I can immediately see two problems with this, one big and one small. Dawn has already pointed out the "small" one, which is that your concept of atomicity is not well grounded. I surmise, based on the limited information you provided, that you consider, say, a single ASCII character to be "atomic". However, since you can represent any character with a bit sequence, there's no reason your supposedly "atomic" symbols can't be broken down into bits, leaving you with the atoms 0 and 1 only (or FALSE and TRUE if you prefer).

The big problem is that your description of normalization as "The process of replacing duplicates [sic] things with a reference to the original thing" really isn't quite correct. ("The difference between the almost right word and the right word is really a large matter -- 'tis the difference between the lightning-bug and the lightning."--Mark Twain) Normalization removes relationships inadvertantly implied between pieces of data by the design of the database. It doesn't create references, and it doesn't decompose data types.

Since you seem to have disagreed with Marshall before about this, perhaps you could provide an example of the "update anomaly" that decomposing "bob" into its individual characters is supposed to prevent?  

>> > The exact method of normalization and to what extent is practical is
>> > dependent on the data model and its implementation.
>> 
>> No, it's dependent on neither of those.

>
> Then how do you explain that in TDM/XDb1, things are normalized down
> to atomic symbols (a, b, c ...) where as a similar level of
> normalization in RDM is impractical?

Because this process can only be called "normalization" through a vigorous application of the imagination. (And speaking of impracticality, what is it that led you to declare that a database consisting of many "two-columned" tables is impractical?)

-- 
Chris Hoess

Received on Thu Mar 04 2004 - 06:03:19 CET