Message-ID: <49CB39C7.2000008@oss.ntt.co.jp>
Date: Thu, 26 Mar 2009 17:16:07 +0900
From: Tatsuhito Kasahara <kasahara.tatsuhito@oss.ntt.co.jp>
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To: Guillaume Smet <guillaume.smet@gmail.com>
CC: depesz@depesz.com,  pgsql-hackers@postgresql.org
Subject: Re: display previous query string of idle-in-transaction
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	<20090325164859.GB30902@depesz.com>
	<1d4e0c10903251007v500e762bqd3514a0c440b928c@mail.gmail.com>
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Guillaume Smet wrote:
> On Wed, Mar 25, 2009 at 5:48 PM, hubert depesz lubaczewski
> <depesz@depesz.com> wrote:
>> I would love to get it, but when I suggested it some time in the past
>> Tom shot it down as bad idea.
>>
>> http://archives.postgresql.org/message-id/20071016132131.GA4438@depesz.com
> 
> I agree with Tom here. I tracked a lot of idle in transaction problems
> and you need the whole sequence of queries of all the backends to
> really understand what happens.
> The last query executed is mostly useless to solve this sort of
> problem. At least, it was for me in every case I had to deal with.
I think so too. But last-query-string may be a useful *hint*.
It is a hard work to trace the whole sequence of queries.

In most cases, last query string is enough information to solve the
long transaction problem. And I want a easy way to get the informarion.
# last query string is also a key to trace queries.

"COMMIT;BEGIN;idle in transaction" is not a problem on 8.3 or later, but
"(BEGIN;)SOME SQL;idle in transaction" is a problem.

So, main purpose of displaying the last query string is ..
- check whether "idle in transaction (running long time) process
   after SOME SQL" is exists or not.
- check the content of "SOME SQL".

best regards,

-- 
Tatsuhito Kasahara
kasahara.tatsuhito@oss.ntt.co.jp