Which staff handled least number of payments? List the full name and the id.
create table payment (staff_id varchar, PRIMARY KEY (staff_id)); create table staff (first_name varchar, last_name varchar, staff_id varchar, PRIMARY KEY (first_name))
select t1.first_name, t1.last_name, t1.staff_id from staff as t1 join payment as t2 on t1.staff_id = t2.staff_id group by t1.staff_id order by count(*) limit 1