Re: Much Ado About COUNT(*) - Mailing list pgsql-hackers

From Jonah H. Harris
Subject Re: Much Ado About COUNT(*)
Date
Msg-id 41E59B31.2090803@tvi.edu
Whole thread Raw
In response to Re: Much Ado About COUNT(*)  (Bruno Wolff III <bruno@wolff.to>)
List pgsql-hackers
Bruno Wolff III wrote:

>On Wed, Jan 12, 2005 at 14:09:07 -0700,
>  "Jonah H. Harris" <jharris@tvi.edu> wrote:
>
>Please keep stuff posted to the list so that other people can contribute
>and learn from the discussion unless there is a particular reason to
>limited who is involved in the discussion.
>
>  
>
not a problem.

>Perhaps you think that the count is somehow saved in the index so that
>you don't have to scan through the whole index to get the number of
>rows in a table? That isn't the case, but is what creating a materialized
>view would effectively do for you.
>  
>
I understand that the count is not stored in the index.  I am saying 
that it may be faster to generate the count off the keys in the index.

I shouldn't have titled this message COUNT(*) as that isn't the only 
thing I'm trying to accomplish.


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