Types of joins

This section describes the types of joins you can use to obtain specific information.

Cross join
A cross join returns all possible combinations of rows of two tables (also called a Cartesian product).
Join/inner join
An inner join, also known as a simple join, returns rows from joined tables that have matching rows. It does not include rows from either table that have no matching rows in the other.
Left outer join/left join
A left outer join returns all the rows from the left table that are specified in the left outer join clause, not just the rows in which the columns match.
Right outer join/right join
A right outer join returns all the rows from the right table that are specified in the right outer join clause, not just the rows in which the columns match.
Full outer join
A full outer join returns all joined rows from both tables, plus one row for each unmatched left row (extended with nulls on the right), plus one row for each unmatched right row (extended with nulls on the left).

Parent topic: Join overview