Re: Database Design questions

From: Peter Robson <pgro_at_bgs.ac.uk>
Date: Fri, 18 Jun 2004 15:12:56 +0100
Message-ID: <841129218.20040618151256@bgs.ac.uk>

Hi Pallav,

You describe a problem area.

As a general rule, if any single relation (eg 'table') has as many as 130 attributes, I am suspicious that the relation is not in Third Normal Form (TNF). This is not to suggest any weakness on the part of Oracle in dealing with wide tables, of course.

My suspicious were further confirmed when you suggested that all the columns 'are mostly dependent or related to the primary key'. This does suggest your table is not in TNF.

May I encourage you to revisit your total list of attributes (irrespective of the relations / tables they are currently assigned to), and apply some formal normalisation to them? Not to do so will unquestionably store up problems for you in the future.

Of course, once you have normalised to TNF, you may make a judgement in terms of selective de-normalisation, but that should only come after normalisation has been achieved.

hope that helps...

peter
edinburgh

Friday, June 18, 2004, 2:49:23 PM, you wrote:

PK> Hi Design Experts,

PK>     I am in the process of designing a  datamodel for
PK> a new application and I need some advice regarding
PK> that. I have a table with almost 130 columns in it.

<snip>

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Received on Fri Jun 18 2004 - 09:10:05 CDT