On 12/28/2010 02:27 AM, Clemens Eisserer wrote:
> Hi,
>
>> you should take a look at that :
>> http://jdbc.postgresql.org/documentation/83/listennotify.html
>
> Thanks that was exactly what I was looking for :)
> Unfourtunatly there's still polling required, it seems the jdbc driver
> has to issue requests in order to get the notifications.
Actually, in newer versions it doesn't have to poll the server. You can
test to see if there are notifications ready to receive and process them
on a timer loop. You're still polling, but only locally within the JVM;
you're not creating any new network activity.
This does *NOT* work if you're using an SSL socket, though, so you have
to be prepared to fall back to issuing "SELECT 1;" or the like for
server-side polling if you can't use client-side-only polling.
--
Craig Ringer