Part 9 Difference between inner join and left join

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This is one of the very common sql server interview question. Different JOINS in SQL Server are discussed in detail in Part 12 of SQL Server tutorial for beginners video series.
Let's understand the difference with an example.
INNER JOIN returns only the matching rows between the tables involved in the JOIN. Notice that, Pam employee record which does not have a matching DepartmentId in departments table is eliminated from the result-set.
SELECT EmployeeName, DepartmentName
FROM Employees
INNER JOIN Departments
ON Employees.DepartmentID = Departments.DepartmentID
LEFT JOIN returns all rows from left table including non-matching rows. Notice that, Pam employee record which does not have a matching DepartmentId in departments table is also included in the result-set.
SELECT EmployeeName, DepartmentName
FROM Employees
LEFT JOIN Departments
ON Employees.DepartmentID = Departments.DepartmentID
In general there could be several questions on JOINS in a sql server interview. If we understand the basics of JOINS properly, then answering any JOINS related questions should be a cakewalk.
What is the difference between INNER JOIN and RIGHT JOIN
INNER JOIN returns only the matching rows between the tables involved in the JOIN, where as RIGHT JOIN returns all the rows from the right table including the NON-MATCHING rows.
What is the difference between INNER JOIN and FULL JOIN
FULL JOIN returns all the rows from both the left and right tables including the NON-MATCHING rows.
What is the Difference between INNER JOIN and JOIN
There is no difference they are exactly the same. Similarly there is also no difference between
LEFT JOIN and LEFT OUTER JOIN
RIGHT JOIN and RIGHT OUTER JOIN
FULL JOIN and FULL OUTER JOIN