Re: database systems and organizational intelligence

From: Dawn M. Wolthuis <dwolt_at_tincat-group.com>
Date: Thu, 27 May 2004 05:04:38 -0500
Message-ID: <c94eft$sfl$1_at_news.netins.net>


"Alan" <not.me_at_uhuh.rcn.com> wrote in message news:gvdtc.22728$4%3.3430_at_nwrdny01.gnilink.net...
> Top-posting - please don't shoot me.
>
> The definitions, examples, and explanations I've given of functional
> dependency are either quoted directly or paraphrased slightly from
> "Fundamentals of Database Systems" 3rd Ed. by Elmasri & Navathe. This
text
> is used in Masters programs at major universities.

I haven't read this book (do you recommend it?), but from this text you are able to determine that functional dependencies have nothing to do with functions?

> GPA as you have described is an example of "derived" data. It is based on
> data already stored. Of course code and functions (which are just
> pre-written chunks of code)

Functions can be specified with code. A function is, by definition, a relation. I wouldn't call any relation, including a function a chunk of code, but there is the specification (formula) for the function, which is encoded in some way.

> are needed to extract data, but that does not
> mean that code and data are the same thing. You are essentially saying
that
> driving a car and directions to a destination are the same thing.
Directions
> are data (information, actually), driving is code (specific actions taken
to
> affect a certain result). They are two different things.

In that case, source code is data and object code that is "running" is code, right? What about data that is fed as input to code to alter the course (e.g. parameters)? Is it data as coded (source code) and then code when applied during execution or does it remain data throughout? If source code is executed by an interpreter instead of a compiler, then does it switch from being instructions (data) to code when the interpreter is taking it in as parameters? I don't think you have hit the nail on the head with this distinction of directions vs. driving, but I could be wrong (it's happened before).

>
> Or, try this (wish I had thought of this sooner)... data:noun/code:verb,
or
> more accurately, data:subject/code:predicate.

That's a broad stroke, and acceptable as such, so perhaps I'm suggesting that we can verbize the nouns and nounize the verbs and it is not all that clear where to draw the line between code and data.

> The cdt glossary was written by whom? They have what credentials?

It is in process and folks from this list are contributing, so the credentials are varied.
--dawn

<snip> Received on Thu May 27 2004 - 12:04:38 CEST

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