A FULL JOIN returns all the rows from the joined tables, whether they are matched or not i.e. you can say a full join combines the functions of a LEFT JOIN and a RIGHT JOIN.
FULL OUTER JOIN keyword returns all records when there is a match in
left (table1) or right (table2) table records.
FULL OUTER JOIN and
FULL JOIN are the same.
In this tutorial we will use the well-known Northwind sample database.
The following SQL statement selects all customers, and all orders:
FULL OUTER JOIN keyword returns all matching
records from both tables whether the other table matches or not. So, if
there are rows in "Customers" that do not have matches in "Orders", or if there
are rows in "Orders" that do not have matches in "Customers", those rows will be
listed as well.