Re: Just one more anecdote

David Cressey wrote:
> "Mike" <mike_at_sherrillshelton.net> wrote in message
> news:1122468034.924778.194610_at_z14g2000cwz.googlegroups.com...
> > dawn wrote:
> >
> > [snip]
> > >As much as
> > >we might want to think otherwise, even the design of a conceptual data
> > >model is influenced by the designer's knowledge of the target dbms.
> > [snip]
> >
> > Speak for yourself, please.

Of course, I was talking about everyone except for me ;-)

> > A conceptual model describes how a piece the world works; you don't
> > even need a computer to do that. I translate conceptual models into
> > logical (relational) models to make sure I've accounted for all the
> > constraints I've found. My target platforms range from SQL dbms to
> > awk/m4 utilities controlled by shell scripts. I never consider the
> > target platform until I start accounting for all the constraints I've
> > uncovered.
> >
>
> Hear, hear!
>
> You've just outlined, in precise terms, the distinction between analysis and
> design.

What you wrote is true in theory, but I did a little look at what passed under that category on various web pages and it was interesting that when there what I might consider attributes of an entity (they don't exist when the entity is gone), those are sometimes split out if their value would be a list or a tuple already in the conceptual model.  I'll figure, then, that my idea of a conceptual model is closer to yours.

Describing a piece of the world does entail design in that it is not objective. How we perceive the world and zero in on what we consider to be relevant is a creative, design task too, even if under the "analysis" umbrella. If it were not, any two experienced, high aptitude modelers would come up with the same model. That is rarely the case, with deviations even greater in the logical model.

> Many times, we engage in unconscious design when we think that what we are
> doing is actually analysis. When we do that,
> we reframe the original problem. If we do so in a positive way, it's
> serendipity. If we do so in a negative way, it's "just one of those
> things". But it isn't. It's flawed analysis.
>
There is no such thing as complete objectivity when working with language. All such analysis is flawed. But I will agree that some analysis is better than others.

>
> Anyway, thanks for your comments! really!
Hey, you didn't say that when you replid to me, David. smiles. --dawn Received on Wed Jul 27 2005 - 16:39:03 CEST