From the Tables view, you can edit the tables by clicking on the pencil in section [2 ] or [4]. If you edit the Locations table, you can see the following:
The screen that appears on editing the Locations table
The first section shows again a quick overview of the table name, rows, and fields. On the right side, you have the Unpivot button, which allows you to swap columns by rows, the Add field button that you can use to add calculated fields to the table, and the last button, Select data from source, used to update the data from the source.