Message-ID: <49D06FD7.7030906@oss.ntt.co.jp>
Date: Mon, 30 Mar 2009 16:08:07 +0900
From: Tatsuhito Kasahara <kasahara.tatsuhito@oss.ntt.co.jp>
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To: Guillaume Smet <guillaume.smet@gmail.com>
CC: Simon Riggs <simon@2ndquadrant.com>,  pgsql-hackers@postgresql.org
Subject: Re: display previous query string of idle-in-transaction
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(Sorry for delay..)

Guillaume Smet wrote:
> Being able to detect which application is running which query on the
> very same database with the very same user seems like something not so
> obvious and the use case seems to be pretty narrow. And IMHO, even if
> we suppose you can make the difference between the applications with
> only one query, you won't be able to limit your investigation to this
> application.
Yes, I won't be able to *completely* detect which application is running
long transaction with a last query.

But, as I said, I can get a hint for guessing causes from it.
And, as Simon said, I can detect a problem point with collaboration
from other information (app's log, app's source, operation procedure, and so on).

> So, in fact, I'm still not convinced. Could you detail a bit more how
> you plan to use it?
Well, Now, I can't get enough information from pg_stat_activity.
So, I have to check huge logs or reproduce the same problem.
(They are annoying works.)

If I can check last and more queries, I can use it as a hint for narrowing
down problem points with app's log and so on.
# And search the point and fix (or suggesting action) it.

I hope it would be able to narrowing down problem points more easily.

Best regards,
-- 
Tatsuhito Kasahara
kasahara.tatsuhito@oss.ntt.co.jp