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).
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