Re: LISTEN/NOTIFY for lightweight replication

Ted Shab wrote:
> Richard,
>
> Thanks for the response.
>
> I'll look into both the dblink and iirc.
>
> Do you know of any extended examples of either?

dblink is in the contrib/ folder of the source distribution and possibly
your packaged version if you use such a thing. Never needed it myself,
but the documentation looks clear enough.

As for listen/notify possibly dropping duplicate notifications... Ah!
it's in the "SQL COMMANDS" reference part of the manuals

NOTIFY behaves like Unix signals in one important respect: if the same
condition name is signaled multiple times in quick succession,
recipients may get only one notify event for several executions of
NOTIFY. So it is a bad idea to depend on the number of notifies
received. Instead, use NOTIFY to wake up applications that need to pay
attention to something, and use a database object (such as a sequence)
to keep track of what happened or how many times it happened.

--
   Richard Huxton
   Archonet Ltd