How to Use Natural Joins

A natural join is a join operation that matches values from columns that have the same name on each of the tables participating in the join For example. if we code a natural join using the Countries and Regions tables in the HR schema, the join column would be region_id. In general, the natural join will perform the join on all columns that have identical names.

To learn how to use natural joins, follow these steps:

1. You'll need to download and install Oracle 12c. The instructions for the setup can be found in How to use sample schemas. Follow steps 1 through 4 before proceeding to the next step.
2. Let's display country name and its region name using a natural join. Execute the following select:
   
   Note that I have displayed the first part of the output that contains 25 countries overall. The natural join will select region_id as the join column because the column appears in both tables with the same name.