Re: deadlock in single-row select-for-update + update scenario? How could it happen? - Mailing list pgsql-general

From hubert depesz lubaczewski
Subject Re: deadlock in single-row select-for-update + update scenario? How could it happen?
Date
Msg-id CAKrjmhdm-7a4Og_y8=MRUzs7NkK4t+iPG14bX-svTBca44a1oA@mail.gmail.com
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In response to Re: deadlock in single-row select-for-update + update scenario? How could it happen?  (Adrian Klaver <adrian.klaver@aklaver.com>)
Responses Re: deadlock in single-row select-for-update + update scenario? How could it happen?  (Adrian Klaver <adrian.klaver@aklaver.com>)
Re: deadlock in single-row select-for-update + update scenario? How could it happen?  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
On Fri, Aug 22, 2014 at 6:45 PM, Adrian Klaver <adrian.klaver@aklaver.com> wrote:
So process 66017 and 66014 are blocking each because they are running the exact same queries. The interesting part is the process with the lower pid is starting later then the none with the higher pid.

Locking is obvious. But why deadlock? There is just single row, and it shouldn't be able to deadlock on it?!
 
So what exactly is 'importer' and what does it do?

Some software written by some guy. Runs lots of queries, but the only problem we have is with these transactions.
 
Also what is this (59303)?

log_line_prefix is  '%m %r %p %u %d ' so it's port number.

depesz

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