List the name of staff who has been assigned multiple jobs.
CREATE TABLE staff (staff_name VARCHAR, staff_id VARCHAR); CREATE TABLE staff_department_assignments (staff_id VARCHAR)
[SQL] SELECT T1.staff_name FROM staff AS T1 JOIN staff_department_assignments AS T2 ON T1.staff_id = T2.staff_id GROUP BY T2.staff_id HAVING COUNT(*) > 1 [/SQL]