Date: Fri, 17 May 2019 17:01:29 -0700
From: Andres Freund <andres@anarazel.de>
To: Ashwin Agrawal <aagrawal@pivotal.io>
Cc: Heikki Linnakangas <hlinnaka@iki.fi>, Tom Lane <tgl@sss.pgh.pa.us>,
	Justin Pryzby <pryzby@telsasoft.com>,
	Haribabu Kommi <kommi.haribabu@gmail.com>,
	Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>,
	Alvaro Herrera <alvherre@2ndquadrant.com>,
	David Rowley <david.rowley@2ndquadrant.com>,
	Robert Haas <robertmhaas@gmail.com>, Asim R P <apraveen@pivotal.io>,
	PostgreSQL mailing lists <pgsql-hackers@postgresql.org>,
	Dmitry Dolgov <9erthalion6@gmail.com>,
	Alexander Korotkov <a.korotkov@postgrespro.ru>
Subject: Re: Pluggable Storage - Andres's take
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Hi,

On 2019-05-17 16:56:04 -0700, Ashwin Agrawal wrote:
> Question on the patch, if not too late
> Why call table_beginscan() in TidNext() and not in ExecInitTidScan() ?
> Seems cleaner to have it in ExecInitTidScan().

Largely because it's symmetrical to where most other scans are started (
c.f. nodeSeqscan.c, nodeIndexscan.c). But also, there's no need to incur
the cost of a smgrnblocks() etc when the node might never actually be
reached during execution.

Greetings,

Andres Freund