How To Write an Inner Join with the WHERE Clause

Q

How To Write an Inner Join with the WHERE Clause? - Oracle DBA FAQ - Understanding SQL SELECT Query Statements

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A

If you don't want to use the INNER JOIN ... ON clause to write an inner join, you can put the join condition in the WHERE clause as shown in the following query example:

SQL> SELECT d.department_name, e.first_name, e.last_name 
  2  FROM departments d, employees e 
  3  WHERE d.manager_id = e.employee_id;

DEPARTMENT_NAME           FIRST_NAME           LAST_NAME
-------------------- -------------------- --------------
Administration            Jennifer             Whalen
Marketing                 Michael              Hartstein
Purchasing                Den                  Raphaely
Human Resources           Susan                Mavris
Shipping                  Adam                 Fripp
IT                        Alexander            Hunold
......

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