Re: What's faster: value of 0 or NULL with index

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Тема Re: What's faster: value of 0 or NULL with index
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Msg-id 20001210220624.A97371@over-yonder.net
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Ответ на What's faster: value of 0 or NULL with index  (Alvar Freude <alvar.freude@merz-akademie.de>)
Ответы Re: What's faster: value of 0 or NULL with index  (Tom Lane <tgl@sss.pgh.pa.us>)
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On Mon, Dec 11, 2000 at 04:28:24AM +0100, some SMTP stream spewed forth:
> Hi,
>
> I'm thinking about, what might be faster on SELECTs: a column with index
> which is NOT NULL and takes the value of 0 or a column which can take
> the NULL value instead of 0, also with index.
>
> My feeling sais, that 0 and NOT NULL should be a lot more faster, but
> perhaps it's not true?

If your SELECT uses the index on the NOT NULL column, then yes, the
indexed 0 should be faster. I think it takes less space as well.(?)

gh

>
>
> bye
>   Alvar
>
>
> --
> Alvar C.H. Freude  |  alvar.freude@merz-akademie.de
>
>     Demo: http://www.online-demonstration.org/  |  Mach mit!
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