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Re: A Normalization Question

From: Jan Hidders <jan.hidders_at_REMOVETHIS.pandora.be>
Date: Mon, 12 Jul 2004 23:16:20 GMT
Message-Id: <pan.2004.07.12.23.16.43.614886_at_REMOVETHIS.pandora.be> 






On Mon, 12 Jul 2004 16:06:37 -0700, Neo wrote:


>> What you have to show is that if I give you the tuple
>> ("Green", "Yellow", ???)
>> you can derive what the third string was. 




> 

> I never claimed that I can derive the third string in the above tuple.


> What I claim is that the string 'brown' (which is the name of three

> different things) is redundant in the following tuple and then

> proceeded to show how to normalize it.

> 

> ID  Person  Color   Street

> 1   'brown' 'brown' 'brown'




Yes, and as I explained before, if I give you the tuple
(1,"brown","brown",???) and you cannot know what the third string is, then
the third string is by definition not logically redundant. Since this
holds for all three strings it follows that there is no logical redundancy
here and hence there is nothing to be normalized here.



    
  
  •   Jan Hidders



Received on Tue Jul 13 2004 - 01:16:20 CEST












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