Re: Lucid statement of the MV vs RM position?

From: dawn <dawnwolthuis_at_gmail.com>
Date: 3 May 2006 07:47:10 -0700
Message-ID: <1146667630.142429.76890_at_j33g2000cwa.googlegroups.com>

Jon Heggland wrote:
> dawn wrote:
> > Jon Heggland wrote:
> >> So now user-defined datatypes violate 1NF as well?
> >
> > Only if they would be in the category of repeating groups or "nonsimple
> > domains" such as list-valued attributes.
>
> Then please say so. You're confusing the issue even more than usual with
> such imprecise statements.

Rats, I was trying to be precise with that one, indicating that it was the added features of RVAs and UDTs that could provide us now with data in a form that was originally excluded with the 1NF term.

> Whether a type is user-defined or not is
> supremely irrelevant.

I completely agree. I know I'm coming from a different perspective and try my best to do all of the translation so that you don't have to cut me slack, but for any you are willing to give me, I thank you.

> (BTW, what "group" is "repeated" in a list of (say) integers?)

A group with arity = 1?
I would love to have precisely the terminology that works for folks when talking about what Codd and, subsequently, SQL, text books, etc were ruling out when they said that data were in 1NF. I took the one phrase from Codd's 1970 paper and the other from elsewhere in hopes of clarity. Since NF2, standing for Non-First Normal Form, is no longer the Non of 1NF by many of today's definitions; "normalize" makes people think of higher normal forms than that-which-was-known-as-1NF; "nonsimple domains" is no more precise than use of the terms scalar or atomic; "repeating groups" seemed worth injecting in hopes of clarifying.

So, Jon, I appreciate you discussing this with me without even if my perspective and terminology might be different, but it would be most helpful if you could give me a term that works for you that relates to what Codd termed "normalization" in his 1970 paper. Too many times I have been asked to clarify, been called an "idiot" (and yes, that does wear on me), or had to have this same conversation, so I clearly need to learn the vocabularly that will work for you and others with your perspective. Would you possibly consider helping me out on this one? What is the "feature" of SQL-92 and before that is/was taught as a key component of relational theory in college courses, that arose from Codd's original meaning of normalization and, subsequently, 1NF about which I am attempting to chat with you? Which if the following resonate with you?

1NF
normalize(d)
no repeating groups
relations with each tuple composed of only scalar values

...atomic values
...simple values
...simple domains

no nonsimple domains
no nested structures
no relation-valued attribute nor list-valued attributes nor bag-valued attributes
non-NF2 (gotta love that one)

Others?

Thanks in advance. --dawn Received on Wed May 03 2006 - 16:47:10 CEST