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Re: So what's null then if it's not nothing?

From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Fri, 25 Nov 2005 00:47:24 +0100
Message-ID: <43865061$0$11061$e4fe514c@news.xs4all.nl>


Alexandr Savinov wrote:
> Jon Heggland schrieb:
>

>> In article <1132798608.160942.270970_at_o13g2000cwo.googlegroups.com>, 
>> michael_at_preece.net says...
>>
>>> If you have a text/string field and it can have an empty string what
>>> have you got? What is the value of the data? How does that value differ
>>> from "no value at all"? Question mark.
>>
>>
>>
>> Are two variables/"fields" (of the same type) with "no value at all" 
>> equal?

>
>
> The question does not make sense because we cannot talking about things
> that do not exist. In particular, it does not make sense to ask if two
> things that do not exist are equal or not.

Yet it is a syntactically correct question to ask in any query language. Let me rephrase: while it is true that it makes no sense, there is no formal reason why it shouldn't. Received on Thu Nov 24 2005 - 17:47:24 CST

Original text of this message

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