Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VOsu6-0005mq-Tr for pgsql-performance@arkaria.postgresql.org; Wed, 25 Sep 2013 17:29:35 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1VOsu5-0006t9-W0 for pgsql-performance@arkaria.postgresql.org; Wed, 25 Sep 2013 17:29:34 +0000 Received: from makus.postgresql.org ([2001:4800:7903:4::125]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VOsu4-0006t2-LT for pgsql-performance@postgresql.org; Wed, 25 Sep 2013 17:29:32 +0000 Received: from smtp.01.com ([199.36.142.181]) by makus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VOstt-0003Gy-5J for pgsql-performance@postgresql.org; Wed, 25 Sep 2013 17:29:31 +0000 Received: from localhost (localhost [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id 31F0F3900EA for ; Wed, 25 Sep 2013 12:29:20 -0500 (CDT) X-Virus-Scanned: amavisd-new at smtp-out-2.01.com Received: from smtp.01.com ([127.0.0.1]) by localhost (smtp-out-2.01.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id vv7JfSdX-A1S for ; Wed, 25 Sep 2013 12:29:20 -0500 (CDT) Received: from smtp.01.com (localhost [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id 12B073900EB for ; Wed, 25 Sep 2013 12:29:20 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id EFE533900F3 for ; Wed, 25 Sep 2013 12:29:19 -0500 (CDT) X-Virus-Scanned: amavisd-new at smtp-out-2.01.com Received: from smtp.01.com ([127.0.0.1]) by localhost (smtp-out-2.01.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id Cm9KpvDHjqj6 for ; Wed, 25 Sep 2013 12:29:19 -0500 (CDT) Received: from [172.47.23.102] (50-1-86-157.dsl.dynamic.sonic.net [50.1.86.157]) by smtp-out-2.01.com (Postfix) with ESMTPSA id 79E313900EB for ; Wed, 25 Sep 2013 12:29:19 -0500 (CDT) Message-ID: <52431D6B.30302@agliodbs.com> Date: Wed, 25 Sep 2013 10:29:15 -0700 From: Josh Berkus Organization: PostgreSQL Experts Inc. User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130803 Thunderbird/17.0.8 MIME-Version: 1.0 To: pgsql-performance@postgresql.org Subject: Re: Why is n_distinct always -1 for range types? References: <523B62CF.5080502@agliodbs.com> In-Reply-To: X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -0.0 (/) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org 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 -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance