Date: Sat, 16 Oct 2004 17:49:29 -0700
From: Steven Klassen <sklassen@commandprompt.com>
To: "C. Bensend" <benny@bennyvision.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Inserting into table only if the row does not already
Message-ID: <20041017004929.GB19149@commandprompt.com>
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* C. Bensend <benny@bennyvision.com> [2004-10-15 08:14:51 -0500]:

> Concurrency shouldn't be an issue - this is a perl script running
> from cron. The only concurrency that will ever happen is if I'm a
> bonehead and I run the script manually right as cron kicks off
> another copy.

Even cron'd scripts can run amok. Lock files are great as a CYA
measure even if you're relatively certain there will be no opportunity
for one copy to step on the next.

I once had a cron'd script mail upper management every hour I was on
vacation. You can imagine how long it was until I got another vacation
request approved. ;)

-- 
Steven Klassen - Lead Programmer
Command Prompt, Inc. - http://www.commandprompt.com/
PostgreSQL Replication & Support Services, (503) 667-4564