17.2. Class and Class of Class
is a set whose membership does not change. However, this does not mean that the members we
about do not change. If one
has different membership from another, then they are different. If one class has the same membership as another, then they are the same.
I have shown the
as entity types.
is also shown in
as the relationship type
is also shown as the relationship type
. The only difference is that when represented by an entity type, the
can itself have attributes and
relationship has a ...