Re: Getting "This ResultSet is closed" exceptions

From: Dave Cramer <pg(at)fastcrypt(dot)com>
To: Paul Tomblin <ptomblin(at)gmail(dot)com>
Cc: pgsql-jdbc(at)postgresql(dot)org
Subject: Re: Getting "This ResultSet is closed" exceptions
Date: 2008-02-18 23:31:16
Message-ID: 90F06A2B-BCAD-4556-9CD6-7B05192AC9E6@fastcrypt.com
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On 18-Feb-08, at 2:48 PM, Paul Tomblin wrote:

> On Feb 18, 2008 2:10 PM, Andres Olarte <olarte(dot)andres(at)gmail(dot)com>
> wrote:
>> You might go for using a single connection per thread. Works for me.
>
> Forgive a possibly stupid question, but how would a class know whether
> there is a Connection for this thread already? I use a simple static
> to hold the Connection, and so I get one for the whole program. But
> there is a lot of asynchronous stuff going on with GUI callbacks,
> external "messages" and RMI calls, etc. Do I have to create and
> destroy a connection in every callback, or use some sort of thread
> pooling system? A previous engineer on this project had one subsystem
> that was creating a new database connection every second, and then
> closing it a few milliseconds later - that seems like madness to me.

And it was/is madness. Yes you want pooling mechanism, and I don't
think a single connection for the whole program is a good thing.
Certainly if you have async callbacks it's very likely you are
stomping on statements.

Dave
>
>
>
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> return to me to aid, comfort and restrain.
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