Natural join if no common attributes

cartesian-product, cross-join, natural-join, relational-algebra, relational-database

Solution

If there are no attributes in common between two relations and you perform a `natural join`, it will return the `cartesian product` of the two relations.

Problem

What will natural join return in relational algebra if tables don't have attributes with same names? Will it be null or the same as cross join (cross product) (Cartesian product)?

Original source