Re: meaning of default_statistics_target - Mailing list pgsql-general

From Alvaro Herrera
Subject Re: meaning of default_statistics_target
Date
Msg-id 20080428145739.GA5761@alvh.no-ip.org
Whole thread Raw
In response to Re: meaning of default_statistics_target  (Martin Marques <martin@marquesminen.com.ar>)
List pgsql-general
Martin Marques escribió:

> Is the value measured in some scale, or does it depend on something
> internal? What does 1000 mean?

1000 histogram and MCV entries, and also a larger sample:

>> Increasing the target also increases the number of rows that ANALYZE
>> samples to prepare the stats, so you should theoretically get more
>> accurate stats for the other columns too, even though they'll still get
>> boiled down to the same array lengths as before.

How larger is the sample, I don't know.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

pgsql-general by date:

Previous
From: Martin Marques
Date:
Subject: Re: meaning of default_statistics_target
Next
From: Chris Browne
Date:
Subject: Re: How to modify ENUM datatypes?