Re: Any concrete example of BNCF ???

I just finished scanning the first of the two articles.

Without taking any time for reflection, I have two instant reactions:

Normalization discourses never adequately answered the question of whether normalization is a method of analysis or a method of design. In all, the examples, just like the one you cited, it appears on the surface that what we are doing is designing tables (at least as far as deciding which columns go in which tables). The diagrams tend to make it look like table design is what normalization is about.

But what we are really doing, if you read the narrative carefully, is discovering the functional dependencies. The functional dependencies are NOT derivable from the sample data, contrary to what is often said. Instead, the sample data, and the apparent lack of full normalization that we see, suggest questions we can ask the subject matter experts in order to discover the true functional dependencies.

Asking those questions, and recording the answers, is analysis, not design.

Now turning to your ORM example. I've got to read this more slowly before commenting at length.
But I want to quote one tiny little piece of what you wrote: "the sample data and a little bit of knowledge of the UoD" . That little bit of knowledge is the result of subject expertise or, if its in the minds of IT people, the result of analysis.

Now let me tie these two together. When Normalization was invented, data analysis was usually done by what we now call reverse engineering. That is, we started with some data stored on punched cards, magnetic tape, sequential files on disk, or maybe indexed files, and discovered the "little bit of knowledge of the Uod" by asking questions. Normalization helped by telling us which questions to ask.

When ORM was invented, however, the ideas of models and analysis were much more developed. It stands to reason, therefore, that we are going to start, as you suggest, with a little bit of knowledge already captured before we begin to do ORM. That makes the whole process more design oriented and less analysis oriented.

As to whether I "like" ORM better than normalization, I'm going to have to read the articles in more depth. Please bear with me.

Scot A. Becker wrote in message ...
>I have two articles that may interest you. The first is at:
>http://www.inconcept.com/JCM/August1998/becker.html and the second is at:
>http://www.inconcept.com/JCM/June1999/becker.html.
>
Received on Fri May 12 2000 - 00:00:00 CEST