Re: Transaction callback

Kevin Field <kev(at)brantaero(dot)com> writes:

> http://archives.postgresql.org/pgsql-hackers/2004-01/msg00861.php
>
> (Just to dredge up another old thread...)
>
>> While its true that a post-commit operation cannot modify a database, it
>> might still for instance propagate the outcome of the transaction to another
>> resource outside of the database, it might invalidate a transaction local
>> in-memory cache, or it might clear resources occupied in memory for a rule
>> system, etc.
>
> This is exactly what I'd like to do. Is there a way to do it nowadays? What
> I'm going for is an AJAX app that doesn't need to poll the server, but rather
> can have the server callback to it when a transaction messes with the data a
> user at which a user is looking.
>
> Any advice would be much appreciated.

I believe that you'll be wanting to take a look at the NOTIFY and LISTEN
commands.

http://www.postgresql.org/docs/8.1/interactive/sql-notify.html
http://www.postgresql.org/docs/8.1/interactive/sql-listen.html

Be seeing you,
--
Jorge Godoy <jgodoy(at)gmail(dot)com>