Re: Question on Structuring Product Attributes

From: Jan Hidders <hidders_at_gmail.com>
Date: 02 Oct 2013 05:59:34 GMT
Message-ID: <1601143370402385874.040013hidders-gmail.com_at_news.xs4all.nl>

Derek Asirvadem <derek.asirvadem_at_gmail.com> wrote:
> This one should not pass unnoticed.
>
> On Monday, 18 February 2013 09:09:15 UTC+11, Eric wrote:

>> 
>> To quote from Codd[1970]:
>> 
>>    "A firstorder predicate calculus suffices
>>     if the collection of relations is in normal form."

>
> Codd specifies what that Normal Form is, that reference is not merely a
> generic or general term.

Indeed. Also note that Codd's claim is not unproblematic. Even if you restrict yourself to the flat relational model, first order logic cannot express many practical queries. So what exactly does he mean by "sufficient" here?

-- 
Jan Hidders

Received on Wed Oct 02 2013 - 07:59:34 CEST