Re: Complete row is fetched ?

From: "A(dot) Kretschmer" <andreas(dot)kretschmer(at)schollglas(dot)com>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: Complete row is fetched ?
Date: 2010-04-16 08:23:44
Message-ID: 20100416082344.GE9356@a-kretschmer.de
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In response to Raymond O'Donnell :
> On a related note, what happens when you do something like this? -
>
> select count(*) ....
>
> Does any data actually get read?

No, it check's only the visibility for each record -> seq-scan.

>
> Is there any difference internally to saying "count(1)" instead?

No, it's the same execution plan.

Regards, Andreas
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Andreas Kretschmer
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