Re: Complete row is fetched ? - Mailing list pgsql-general

From A. Kretschmer
Subject Re: Complete row is fetched ?
Date
Msg-id 20100416082344.GE9356@a-kretschmer.de
Whole thread Raw
In response to Re: Complete row is fetched ?  (Raymond O'Donnell <rod@iol.ie>)
Responses Re: Complete row is fetched ?
List pgsql-general
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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