Date: Mon, 9 Apr 2018 15:48:05 -0300
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Robert Haas <robertmhaas@gmail.com>
Cc: David Rowley <david.rowley@2ndquadrant.com>,
	Amit Langote <amitlangote09@gmail.com>,
	Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>,
	Jesper Pedersen <jesper.pedersen@redhat.com>,
	Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>,
	Beena Emerson <memissemerson@gmail.com>,
	amul sul <sulamul@gmail.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>,
	Dilip Kumar <dilipbalaut@gmail.com>
Subject: Re: [HACKERS] Runtime Partition Pruning
Message-ID: <20180409184805.ieucnlxwnwr2mprt@alvherre.pgsql>
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Robert Haas wrote:
> On Mon, Apr 9, 2018 at 2:28 PM, Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:
> > Robert Haas wrote:

> >> I don't get this.  The executor surely had to (and did) open all of
> >> the relations somewhere even before this patch.
> >
> > I was worried that this coding could be seen as breaking modularity, or
> > trying to do excessive work.  However, after looking closer at it, it
> > doesn't really look like it's the case.  So, nevermind.
> 
> Well what I'm saying is that it shouldn't be necessary.  If the
> relations are being opened already and the pointers to the relcache
> entries are being saved someplace, you shouldn't need to re-open them
> elsewhere to get pointers to the relcache entries.

Oh, okay.  I can look into that.

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