Use external roles to assign role privileges to directory users. External roles are created exactly like database roles. However, they cannot be granted to directory users because these users do not exist in the database. Instead, directory users must be members of groups that are mapped to external roles in the directory.
Directory users mapped to multiple external roles have access to all of them at logon to the database.
For information on mapping directory users to database objects, see Teradata Vantage™ - Analytics Database Security Administration, B035-1100.