SQL OUTER JOIN

Unlike SQL INNER JOIN, SQL OUTER JOIN selects rows from 2 joined tables even there is no matches found.

There are three kind of SQL OUTER JOINs:
SQL LEFT OUTER JOIN
SQL RIGHT OUTER JOIN
SQL FULL OUTER JOIN

SQL OUTER JOIN Example

Table: Employees

Table: Email

Select all the employees with Email address:

SELECT  emp.EmployeeId, emp.FirstName, emp.LastName, Email.Email
FROM Employees AS emp
     LEFT OUTER JOIN Email
     ON emp.EmployeeId = Email.EmployeeId

The result will look like: