Multi-tenancy setup

Hi All, We are hosting an application in the cloud which is managing multiple customers. Customers will be authenticated using the FreeRadius server. We are planning to use the user authentication through the database(PostgreSQL). I have configured the radcheck table and able to make the user authentication successfully. In order to support multiple customers, what are all the options/design available in FreeRadius. One option we are thinking is to modify the schema to introduce customer-id and modify the sql module to support the new schema. If this is possible, please provide pointers in achieving this. If there are other options available, please provide pointers. Thanks, Ila.