PostgreSQLDatabase.CheckForNotifications
From Xojo Documentation
Method
Checks to see if there are any waiting notifications. You will receive notifications as a ReceivedNotification event. If you would like to receive notifications automatically, create a Timer and use it to call CheckForNotifications repeatedly.
Notes
Notifications are received in the PostgreSQLDatabase.ReceivedNotification event handler.
Example
This example is in the Action event of a Timer.
// db is a previously connected PostgreSQLDatabase
db.CheckForNotifications
db.CheckForNotifications