Tuesday, January 13, 2009

What Is Normalization: Part V

This article has moved: What Is Normalization: Part V

4 comments:

Patrick Honorez said...

Very good serie ! I have been teaching Access for a long time and your presentation of Normalization is really clear.
And the fact of chaining this with E-R is a great approach.

Fawad Anwar said...

Wow!
I never knew someone who could 'talk Access' like that.

kino said...

This is a good example of normalization. I am curious about the several forms of Normalization. Most experts only follow the first three. What is the purpose of the last four?

Roger Carlson said...

@ kino
The short answer is...

The first three normal forms: 1) are common to nearly all databases, 2) solve the vast majority of data anomoly problems, and 3) are the easiest to explain to newbies.

The higher normal forms are used for increasingly specialized cases, and depending on the business rules, are often better handled at the application level rather than the database level.

There's a longer answer, but I'll save that for a new post. Stay tuned.