Compatibility roles exist for backward compatibility with versions of SAP Sybase IQ earlier than 16.0. that support authority-based security.
You can grant, revoke, and under specific conditions, deleted compatibility roles. You cannot modify any of the underlying system privileges. However, you can migrate compatibility roles to user-defined roles, and then modify the underlying system privileges. When you migrate a compatibility role, all grantees of the compatibility role are automatically granted the user-defined role.
See Considerations When Upgrading from Pre-16.0 Releases > Understanding Role-Based Security After Upgrading from 15.x in the Migration Guide appropriate to your operating system.