Date: Mon, 29 Jan 2018 10:44:57 -0500
From: Bruce Momjian <bruce@momjian.us>
To: Simon Riggs <simon@2ndquadrant.com>
Cc: Pavel Stehule <pavel.stehule@gmail.com>, Peter Geoghegan <pg@bowt.ie>,
	Alvaro Herrera <alvherre@alvh.no-ip.org>,
	Andrew Dunstan <andrew.dunstan@2ndquadrant.com>,
	Pavan Deolasee <pavan.deolasee@2ndquadrant.com>,
	Robert Haas <robertmhaas@gmail.com>,
	Stephen Frost <sfrost@snowman.net>,
	PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: [HACKERS] MERGE SQL Statement for PG11
Message-ID: <20180129154457.GC11613@momjian.us>
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On Mon, Jan 29, 2018 at 03:12:23PM +0000, Simon Riggs wrote:
> On 29 January 2018 at 14:55, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> 
> > My note was not against MERGE or INSERT ON CONFLICT. If I understand to this
> > topic, I agree so these commands should be implemented separately. But if we
> > use two commands with some intersection, there can be nice to have
> > documentation about recommended use cases. Probably it will be very often
> > question.
> 
> That is more qualitative assessment of each, which I think I will defer on.
> 
> This patch is about implementing the SQL Standard compliant MERGE
> command which is widely used in other databases and by various tools.

Uh, if we know we are going to get question on this, the patch had
better have an explanation of when to use it.  Pushing the problem to
later doesn't seem helpful.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

+ As you are, so once was I.  As I am, so you will be. +
+                      Ancient Roman grave inscription +