From: Josh Berkus <josh@agliodbs.com>
To: postgres performance list <pgsql-performance@postgresql.org>
Subject: Why is n_distinct always -1 for range types?
Date: Thu, 19 Sep 2013 15:47:11 -0500
Message-ID: <523B62CF.5080502@agliodbs.com> (raw)
List-Unsubscribe: <mailto:majordomo@postgresql.org?body=unsub%20pgsql-performance>
Test:
1. create a table with a range type column.
2. insert 1000 identical values into that column.
3. analyze
4. n-distinct will still be listed as -1 (unique) for the column.
Why?
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com
--
Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance
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: josh@agliodbs.com
Subject: Re: Why is n_distinct always -1 for range types?
In-Reply-To: <523B62CF.5080502@agliodbs.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