Message-ID: <554ABF43.40708@proxel.se>
Date: Thu, 07 May 2015 03:26:27 +0200
From: Andreas Karlsson <andreas@proxel.se>
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To: hlinnaka@iki.fi, Peter Geoghegan <pg@heroku.com>,
 Andres Freund <andres@anarazel.de>
CC: Jeff Janes <jeff.janes@gmail.com>, Stephen Frost <sfrost@snowman.net>,
 Dean Rasheed <dean.a.rasheed@gmail.com>, Bruce Momjian <bruce@momjian.us>,
 Pg Hackers <pgsql-hackers@postgresql.org>
Subject: Re: INSERT ... ON CONFLICT UPDATE/IGNORE 4.0
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	<CAM3SWZTU8FgwoMb-vKZv_LsQb75nH=NP9+dCdTj9S4GScMtk=A@mail.gmail.com>
	<20150506152007.GN9855@alap3.anarazel.de>
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On 05/06/2015 09:51 PM, Heikki Linnakangas wrote:
>> So, yes, DO NOTHING does very little - and that is its appeal.
>> Supporting this behavior does not short change those who actually care
>> about the existing tuple sticking around for the duration of their
>> transaction - they have a way of doing that. If you want to document
>> INSERT IGNORE as being primarily an ETL-orientated thing, that would
>> make sense, but let's not hobble that use case.
>
> Yeah, I agree that DO NOTHING should not lock the rows. It might make
> sense to have a DO LOCK variant, which locks the rows, although I don't
> immediately see what the use case would be.

It seems like a very useful feature to me, if you want to upsert 
something into a table with a serial column and get the value of the 
serial column in a RETURNING clause (but not update any fields if there 
is a conflict). Then I am pretty sure I want to lock the row.

Andreas


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