ont.reminder_nbr: number of reminders that are set up to send
po.organizer_rmndr_sent_nbr: number of reminders that have been sent
The number of the first value minus the second value is the number of remaining reminders. However, if the final number is negative then I want to display 0. Is this possible using a decode similar to the one below? If not is there another Oracle function that can be used?