Date: Tue, 13 Aug 2019 11:25:17 -0400
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Amit Langote <amitlangote09@gmail.com>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	Simon Riggs <simon@2ndquadrant.com>,
	yuzuko <yuzukohosoya@gmail.com>,
	shawn wang <shawn.wang.pg@gmail.com>,
	Shawn Wang <shawn.wang@highgo.ca>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Problem with default partition pruning
Message-ID: <20190813152517.GA9767@alvherre.pgsql>
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On 2019-Aug-13, Amit Langote wrote:

> Thanks a lot for revising.  Looks neat, except:
> 
> +     * This is a measure of last resort only to be used because the default
> +     * partition cannot be pruned using the steps; regular pruning, which is
> +     * cheaper, is sufficient when no default partition exists.
> 
> This text appears to imply that the default can *never* be pruned with
> steps.  Maybe, the first sentence should read something like: "...the
> default cannot be pruned using the steps generated from clauses that
> contradict the parent's partition constraint".

Thanks!  I have pushed it with this change.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services