Who Can Create A Role

The CREATE ROLE statement can be executed by:

Administrators
Users with the CREATE ROLE privilege
- Setting system privileges also requires the system privilege CREATE_PRIVILEGED_ROLES

The user executing the CREATE ROLE statement becomes the owner of the role.

Creating a role named SELLERS

CREATE ROLE SELLERS;

Creating a role SELECT_ALL with the system privilege to select from any selectable object

CREATE ROLE SELECT_ALL
  SET SYSTEM PRIVILEGES TO SELECT_ANY_OBJECT_IN_DATABASE;