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Re: NOT IN (NULL) ? - Mailing list pgsql-general

From Raymond O'Donnell
Subject Re: NOT IN (NULL) ?
Date
Msg-id 4CCD9CD1.7010703@iol.ie
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In response to NOT IN (NULL) ?  ("Paul" <magamos@mail.ru>)
List pgsql-general
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On 31/10/2010 16:37, Paul wrote:
> Please, help me.
> Why the condition
> SELECT 5 NOT IN (NULL)
> returns NULL, but not FALSE (as I thought)?

Because NULL basically means "don't know" - so you don't know whether 5
is there or not.

Ray.


--
Raymond O'Donnell :: Galway :: Ireland
rod@iol.ie

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