Re: External (asynchronous) notifications of database updates

Hello Mike,

thanks a lot for your posting!

> Have you considered using LISTEN/NOTIFY? The listener should receive
> notifications only if the notifying transaction commits.

Yes. I've seen them in the documentation _but_ missed the information
about the notification being delivered after the notifier successfuly
commits. Great! This is a (very basic) approach to my problem, although
it requires me to create a mechanism exploring what row was exactly
changed and how. I might readopt the triggers to ask them for some help,
but with caution as race-conditions could easily appear. Thank you for
the clue!

> > I don't know how the various replication tools solve this - do you?
>
> Not sure; maybe some of the people who work on such tools can
> comment.

Still an unresolved issue. Those replication tools must have existed
before the LISTEN/NOTIFY mechanism has been introduced to PG. Have they?

> What do you mean by "notification"? A trigger-based notification? Or
> are you already using LISTEN/NOTIFY?

I meant a trigger-based notification, let's forget this for now.

-

Milan Krcmar