Message-ID: <4C93E81F.7080905@2ndquadrant.com>
Date: Fri, 17 Sep 2010 18:13:51 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: badair@epc-instore.com
CC: pgsql-admin@postgresql.org
Subject: Re: Ingres statdump equivalent for postgresql
References: <1284745176.201931386@192.168.2.231>
In-Reply-To: <1284745176.201931386@192.168.2.231>
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badair@epc-instore.com wrote:
> I'm looking for a tool that will enable me to dump the data frequency histograms
> for a postgresql table.

#!/bin/bash
DB="$1"
TABLE="$2"
psql -d $DB -x -c "SELECT 
tablename,attname,null_frac,avg_width,n_distinct,correlation,most_common_vals,most_common_freqs,histogram_bounds 
FROM pg_stats where tablename='$TABLE'"

Run that, pass it database then table name, and you'll get the data for 
each column in that table.  That should get you started; refer to 
http://www.postgresql.org/docs/current/interactive/catalog-pg-statistic.html 
and to 
http://www.postgresql.org/docs/current/interactive/planner-stats-details.html 
for more details.

-- 
Greg Smith, 2ndQuadrant US greg@2ndQuadrant.com Baltimore, MD
PostgreSQL Training, Services and Support  www.2ndQuadrant.us
Author, "PostgreSQL 9.0 High Performance"    Pre-ordering at:
https://www.packtpub.com/postgresql-9-0-high-performance/book