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From: paul c <toledobythesea@oohay.ac>
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Subject: Re: Does Codd's view of a relational database differ from that ofDate&Darwin?
 [M.Gittens]
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Date: Mon, 06 Jun 2005 16:58:13 GMT
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Xref: dp-news.maxwell.syr.edu comp.databases.theory:31261

Alexandr Savinov wrote:
> paul c schrieb:
> 
>> Alexandr Savinov wrote:
>>
>>>  
>>> ... If something disappears, if something is deleted then acutally we 
>>> get null.
>>
>>
>>
>> i think we get 'false', according to the CWA.
> 
> 
> Actually it is one and the same, i.e., null, false, empty set 
> ...

if they are one and the same then we don't need nulls.  we already have 
boolean true and false.

p