SELECT T2.emp_fname FROM CLASS AS T1 JOIN employee AS T2 ON T1.prof_num  =  T2.emp_num GROUP BY T1.prof_num HAVING count(*)  >  1
Find the first names of professors who are teaching more than one class.
SELECT T2.emp_fname FROM CLASS AS T1 JOIN employee AS T2 ON T1.prof_num = T2.emp_num GROUP BY T1.prof_num HAVING count ( * ) > 1
select t2 . emp_fname from class as t1 join employee as t2 on t1 . prof_num = t2 . emp_num group by t1 . prof_num having count ( * ) > value
Find the first names of professors who are teaching more than one class .