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Re: select count(*); - Mailing list pgsql-general

From	Geoff Winkless
Subject	Re: select count(*);
Date	June 11, 2015 17:13:28
Msg-id	CAEzk6fdowS0_6ntvrwEWu_KVKRL+qGiOdavvrbU18FeL0q_TmQ@mail.gmail.com Whole thread Raw
In response to	Re: select count(*); (Marc Mamin <M.Mamin@intershop.de>)
Responses	Re: select count(*); (Marc Mamin <M.Mamin@intershop.de>)
List	pgsql-general

On 11 June 2015 at 15:05, Marc Mamin <M.Mamin@intershop.de> wrote:

That's the point. * has no meaning without FROM

But COUNT(*)
does have meaning - it means "the number of rows".

It's not counting the number of columns in the row, so postgres doesn't need to know what columns exist in the row to return a row count.

Geoff

From: Francisco Olarte
Date: 11 June 2015, 17:05:39
Subject: Re: Planner cost adjustments

From: Marc Mamin
Date: 11 June 2015, 17:17:28
Subject: Re: select count(*);