Which department has the most professors with a Ph.D.?
SELECT T2.dept_name ,  T1.dept_code FROM professor AS T1 JOIN department AS T2 ON T1.dept_code  =  T2.dept_code WHERE T1.prof_high_degree  =  'Ph.D.' GROUP BY T1.dept_code ORDER BY count(*) DESC LIMIT 1
department with most professors with a Ph.D. refers to MAX(COUNT(professor where prof_high_degree = 'Ph.D.')); department name refers to dept_name; department code refers to dept_code; joining tables refers to JOIN;