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Message-ID: <49CC75E3.7010101@oss.ntt.co.jp>
Date: Fri, 27 Mar 2009 15:44:51 +0900
From: Tatsuhito Kasahara <kasahara.tatsuhito@oss.ntt.co.jp>
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To: Simon Riggs <simon@2ndQuadrant.com>
CC: pgsql-hackers@postgresql.org
Subject: Re: display previous query string of idle-in-transaction
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Simon Riggs wrote:
>> If we can also check previous query_string of idle-in-transaction,
>> it is useful for analysis of long transaction problem.
> 
> I'm more interested in the problem itself. Why do you think there is a
> problem and why does knowing this help you? I had similar problems
> recently, so I'm interested in thoughts around this.
In many case, applications don't know what queries they are doing.
So, if a long transaction problem (unworking defragmnetation by HOT and
VACUUM) occured, I don't understand which application is the cause with
only "<IDLE> in transaction" message.

But if I can also check last query string, I guess which apllication
do that and point out the problem point.
# As I said, I think a long transaction is not a problem itself.

Does that answer your question ?

Best regards,

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