NATURAL JOIN doesn't require column names because it always joins the two tables on the columns with the same name.
In our example, students and rooms have been joined on the column
id, which doesn't really make much sense. In our dormitory, the construction
NATURAL JOIN room;
gives the same result as the following query:
ON student.id = room.id;
You can, however, construct your tables in such a way that
NATURAL JOIN comes in handy. If you had the following tables:
car(car_id, brand, model)
owner(owner_id, name, car_id)
Then it would make perfect sense to use
NATURAL JOIN because it would join the two tables on the
car_id column. You would then need fewer keyboard strokes to join two tables.