Natural joins of views and derived tables

An extension to the ANSI/ISO SQL standard is that you can specify views or derived tables on either side of a natural join. In the following statement,

SELECT *
FROM View1 NATURAL JOIN View2;

the columns in View1 are compared to the columns in View2. If, for example, a column called EmployeeID is found to occur in both views, and there are no other columns that have identical names, then the generated join condition is (View1.EmployeeID = View2.EmployeeID).

 Example