Which professionals have done at least two treatments? List the professional's id, role, and first name.
create table professionals (professional_id varchar, role_code varchar, first_name varchar, PRIMARY KEY (professional_id)); create table treatments (professional_id varchar, PRIMARY KEY (professional_id))
select t1.professional_id, t1.role_code, t1.first_name from professionals as t1 join treatments as t2 on t1.professional_id = t2.professional_id group by t1.professional_id having count(*) >= 2