Re: Why is n_distinct always -1 for range types?

From: Josh Berkus <josh(at)agliodbs(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Why is n_distinct always -1 for range types?
Date: 2013-09-25 17:29:15
Message-ID: 52431D6B.30302@agliodbs.com
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On 09/19/2013 01:47 PM, Josh Berkus wrote:
> 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?
>

Anyone?

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com

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