Re: normalization

I'm signing up for the denormalised team...

The resource cost of maintaining a calculated field the few times a row is inserted or updated would seem to be a lot less than resource cost of re-calculating it everytime it's selected (over and over and over).

And if we're talking about summary fields, IMO, these should not be maintained by triggers, because I hate triggers, and also because I believe summaries should be maintain asyncronously. Maintaining summaries syncronously means you serialise on the highest level of summary.

Malcolm.

On 01/11/05, Chris Stephens <cstephens16_at_gmail.com> wrote:
> There is a discussion going on at work concerning calculated fields.
>
> I am claiming that any calculated field in a table is a violation of
> at least 3NF if not 2NF. I can find all sorts of references on the
> web that justify my position but nothing that directly says this
> violates normalization rules.
>
> The person who i disagree with is claiming that 'technically',
> calculated fields do not violate 3NF. They are just not recommended.
> I am unable to find anything on the web coinciding with this argument.
>
> Anyone know of a site with a direct statement that calcualted fields
> violate 2NF/3NF?
>
> thanks,
> chris
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> http://www.freelists.org/webpage/oracle-l
>
>
>

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