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Re: more problems with count(*) on large table - Mailing list pgsql-general

From A. Kretschmer
Subject Re: more problems with count(*) on large table
Date
Msg-id 20070928163817.GA20354@a-kretschmer.de
Whole thread Raw
In response to more problems with count(*) on large table  (Mike Charnoky <noky@nextbus.com>)
Responses Re: more problems with count(*) on large table  (Alvaro Herrera <alvherre@commandprompt.com>)
Re: more problems with count(*) on large table  (Alban Hertroys <a.hertroys@magproductions.nl>)
List pgsql-general
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am  Fri, dem 28.09.2007, um 11:56:46 -0400 mailte Mike Charnoky folgendes:
> Hi,
>
> I am still having problems performing a count(*) on a large table.  This
>
> Now, certain count(*) queries are failing to complete for certain time
> ranges (I killed the query after about 24 hours).  The table is indexed
> on a timestamp field.  Here is one query that hangs:

Again: an index can't help! Because of MVCC: 'select count(*)' without
WHERE-condition forces an seq. table-scan.


Andreas
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Andreas Kretschmer
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