Re: display previous query string of idle-in-transaction

On Fri, 2009-03-27 at 15:44 +0900, Tatsuhito Kasahara wrote:
> 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 ?

Not really. I want to understand the actual problem with
idle-in-transaction so we can consider all ways to solve it, rather than
just focus on one method.

-- Simon Riggs           www.2ndQuadrant.comPostgreSQL Training, Services and Support