Re: A database design question

From: Marc Baime <mbaime_at_gte.net>
Date: 1997/07/31
Message-ID: <5rosjo$nnh$1@gte1.gte.net>#1/1

On Wed, 30 Jul 1997 15:07:04 -0500, Sanjay Rallapally <c696346_at_showme.missouri.edu> wrote:

><HTML>
>Its me again,
><BR>I am curious abut the level of database  normalization that is
>followd in the real-world . How rigidly do u guys follow the database design
>rules regarding normalization? Lastly, when is it better to have an unnormalized
>table, than an unnormalized one? I mean, how useful are indexes as against
>having a normalizzed table
><BR> </HTML>
>

It might be worth your while to do a little reading in this area so you have a better understanding. There are lots of books around that address data modeling. I suggest you pick one up. As to my thoughts, in general, it is good to start out with at least a 3rd normal form design. This is sometimes expressed as all extended attributes (those which are not part of the primary key) relying on the key, the whole key, and nothing but the key. Once the data design is in 3rd normal form you can use this as your first cut physical database. From there, you can denormalize the data as neccesary to enhance performance. Many people do not create data in true third normal form as such a design often seems extreme to application designers/implementers. Anyway I've probably confused rather than clarified the issue. A thumbnail sketch of normalization/data modeling does not do the subject justice. My recommendation is that you study up a bit and you'll be able to make better decisions regarding normalization. In most big shops, Data Base Modeling and Data Base Administration are two separate areas which work together to supply corporate data support.

Regards...Marc Baime Received on Thu Jul 31 1997 - 00:00:00 CDT