EXPLICIT INNER JOIN
-------------------


SELECT *
FROM employee INNER JOIN department ON employee.DepartmentID = department.DepartmentID;


(Omits employees with no department, and departments with no employees)






IMPLICIT INNER JOIN (cross join with where-clause filter)
---------------------------------------------------------


SELECT *
FROM employee, department
WHERE employee.DepartmentID = department.DepartmentID;


(Omits employees with no department, and departments with no employees)






LEFT OUTER JOIN
---------------


SELECT *
FROM employee
LEFT OUTER JOIN department ON employee.DepartmentID = department.DepartmentID;


(Includes employees with no department)






RIGHT OUTER JOIN
----------------


SELECT *
FROM employee
RIGHT OUTER JOIN department ON employee.DepartmentID = department.DepartmentID;


(Includes departments with no employees)







FULL OUTER JOIN
---------------


FROM employee
FULL OUTER JOIN department ON employee.DepartmentID = department.DepartmentID;


(Includes employees with no department, and departments with no employees)