Re: [JDBC] Getting "This ResultSet is closed" exceptions

On 18-Feb-08, at 2:48 PM, Paul Tomblin wrote:

> On Feb 18, 2008 2:10 PM, Andres Olarte <olarte.andres@gmail.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
>
>
>
> --
> For my assured failures and derelictions I ask pardon beforehand of my
> betters and my equals in my Calling here assembled, praying that in
> the hour of my temptations, weakness and weariness, the memory of this
> my Obligation and of the company before whom it was entered into, may
> return to me to aid, comfort and restrain.
>
> ---------------------------(end of
> broadcast)---------------------------
> TIP 9: In versions below 8.0, the planner will ignore your desire to
> choose an index scan if your joining column's datatypes do not
> match

---------------------------(end of broadcast)---------------------------
TIP 1: if posting/reading through Usenet, please send an appropriate
       subscribe-nomail command to majordomo@postgresql.org so that your
       message can get through to the mailing list cleanly