This example illustrates use of FULL JOIN action with NATURAL option.
This query retrieves all event names and places where they happen. Venue is attached to event name if value of same named field is equal in both tables. If there is no corresponding venue for event, then NULL is placed beside it. Likewise, if a corresponding event for a venue couldn't be found, NULL is placed to the left of it.
select Event_Name, Venue
from Events naturalfulljoin Venues
orderby Event_Name, Venue