Natural join if no common attributes

Question

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-product (Cartesian operator)?

Answer 1

A cartesian product of two tables will be returned.This is because when we perform any JOIN operation on two tables a cartesian product of those tables is performed and then based on any select condition in WHERE clause the resultant rows are returned.But here as there are no common columns the process stops after cartesian product.