Re: Objects and Relations

From: David BL <>
Date: 23 Feb 2007 18:40:09 -0800
Message-ID: <>

On Feb 24, 9:50 am, paul c <> wrote:
> David BL wrote:
> > On Feb 23, 11:24 am, paul c <> wrote:
> >>Lemming wrote:
> >>>On Mon, 19 Feb 2007 13:50:55 GMT, Bob Badour
> >>><> wrote:
> >>>> ...
> >>>>Humans tend toward laziness and complacency. Something has to shock them
> >>>>from their revery before they act.
> >>>Blimey, seems like school is out again.
> >>>I'll come back in a week or so. Maybe there will be some grownups
> >>>here by then.
> >>Blimey yourself. Things aren't likely to change in ten years at the
> >>rate this group is going. The thread title, "Objects and Relations"
> >>ought to tell any regular reader that it is about apples and oranges aka
> >>minotaurs and two-legged creatures.
> > Yes, like most on this NG you say that RM+RA is for recording and
> > managing data, while OO is not. Unfortunately this view is
> > simplistic.
> > Consider the following
> > * Images
> > * Text
> > * Source code
> > * Scenegraphs
> > * CAD drawings
> > * Tri-surfaces
> > * Web pages
> > * Sound data
> > * Video data
> > None of these areas appear to be handled particularly well with RM
> > +RA. Yet they all represent problem domains where data needs to be
> > recorded, persisted and managed.
> > ...
> This has come up so many times over the years but it still amazes me as
> to why people are so attracted to such a vague mystical stance. You
> might as well say the King James Bible is a valid topic for this group.

I assume this group is about the recording, representation and management of data.

Perhaps you have a different definition of "data" to mine.

In OO, a thing like an image can be regarded as an Abstract Data Type (ADT). Note well the use of the word "Data" in that term. See Chapter 6 of "Object Oriented Software Construction" by Bertand Meyer. RM doesn't have an exclusive stake on the representation or management of data.

> When you want to talk about this stuff, I think you must qualify what
> you say because most novices confuse appearance with intent. Take an
> image - what is it you would like to state about it?

You did not realise my point? I'm talking about representing these things and processing these things, and not merely stating facts *about* these things. My whole point has been that RM is perfect for the latter but not so good for the former. If you agree with that then please say so.

Do you think "data" only refers to facts about things?

If you think RM is suitable for scenegraphs I would be particularly interested.

> To echo one of the deeper thinkers than I, I reject completely the
> misconception that today's computers or the theory they use can
> understand images in the same way that humans do, no matter what db or
> programming technique they might use.

I agree with that. So? Does this have something to do with this "mystical stance" you're on about.

> Whereas if you want to say which x-y coordinates of which areas in the
> image or photograph are agreed to be taken to stand for the image of the
> person named Codd, then RM is okay. Other interpreations such as
> border photo imagery recognition aren't exactly in the scope of this group.

So what's the scope of this group? Data management or its restriction to merely stating facts about things? Received on Sat Feb 24 2007 - 03:40:09 CET

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