Re: FW: "=" operator vs. "IS"

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От Peter Eisentraut
Тема Re: FW: "=" operator vs. "IS"
Дата
Msg-id 200406291827.48502.peter_e@gmx.net
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Ответ на Re: FW: "=" operator vs. "IS"  (Rich Hall <rhall@micropat.com>)
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Rich Hall wrote:
> My question is why is the form
>
> "(anything) = NULL"
>
> allowed?
>
> Since
>
> "(anything) = NULL" is always Null, this cannot be what the coder
> intended.

Using that same line of argument, why is 1+1 allowed?  The coder clearly 
knows that it is 2, so why is he writing that?  Many queries are 
generated by automatic tools that definitely intend what they say.



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