PostgreSQL Callback Mechanism

Hi All,

PostgreSQL 7.1 Developer's Guide
Ch. 4.2.4 Notification Responses, pg. 27

> If a frontend issues a listen(1) command, the backend will send a
NotificationResponse message whenever a notify(1) command is executed for
the same notification name.

a notify(1) command executed by another client?

PostgreSQL 7.1 Programmer's Guide
Ch. 1.5 Asynchronous Notification, pg 14

> A backend registers its interest in a particular notification with the
LISTEN command...

A backend? But you just said frontend!

How do I make the PostgreSQL server notify me when my view (of the model)
has changed?

I'm reading the documentation with great anticipation; but anybody with
personal experience may be able to direct me to the appropriate
literature.

Thanks,

Patrick Henry, MCDL
Brunswick Ohio, 44212 USA