Date: Fri, 5 Jul 2024 13:05:24 +0200
From: hubert depesz lubaczewski <depesz@depesz.com>
Sender: depesz@depesz.com
To: Murthy Nunna <mnunna@fnal.gov>
Cc: "pgsql-general@lists.postgresql.org" <pgsql-general@lists.postgresql.org>
Subject: Re: psql help
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On Fri, Jul 05, 2024 at 03:54:56AM +0000, Murthy Nunna wrote:
> Sorry, there is no problem with the following statement and the environment variable. It works fine. But it terminates only one PID due to LIMIT 1. I want to terminate all pids that meet this criteria. If I remove LIMIT 1, pg_terminate_backend(pid) will not work as it expects only one pid at a time. So, the question is how to rewrite this psql so it loops through all pids one pid at a time? Thanks in advance for your help.
> 
> SELECT pid, pg_terminate_backend(pid) FROM pg_stat_activity
>     WHERE pid IN (select unnest(pg_blocking_pids(pid)) from pg_stat_activity where cardinality(pg_blocking_pids(pid)) > 0)
>                  and usename = 'DBUSER_10'
>                  and now() - state_change >= interval $a'${TIMEOUT_MINS}'$a
>                  order by now() - state_change >= interval $a'${TIMEOUT_MINS}'$a desc limit 1;

Did you try?

I don't see any reason why it wouldn't work with just 'limit 1' removed.

Best regards,

depesz