From: Greg Smith <greg@2ndquadrant.com>
To: Jesper Krogh <jesper@krogh.cc>
Cc: Ron Mayer <rm_pg@cheapcomplexdevices.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Digesting explain analyze
Date: Thu, 07 Jan 2010 01:39:31 -0500
Message-ID: <4B4581A3.1050401@2ndquadrant.com> (raw)
In-Reply-To: <4B457AD4.8090405@krogh.cc>
References: <4B44E02A.6080109@krogh.cc>
<4B44EC89.7060200@cheapcomplexdevices.com>
<4B457AD4.8090405@krogh.cc>
Jesper Krogh wrote:
> Is it possible to get PG to tell me, how many rows that fits in a
> disk-page. All columns are sitting in "plain" storage according to \d+
> on the table.
>
select relname,round(reltuples / relpages) as "avg_rows_per_page" from
pg_class where relpages > 0;
--
Greg Smith 2ndQuadrant Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com www.2ndQuadrant.com
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: greg@2ndquadrant.com, jesper@krogh.cc, rm_pg@cheapcomplexdevices.com
Subject: Re: Digesting explain analyze
In-Reply-To: <4B4581A3.1050401@2ndquadrant.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox