Table schema:
CREATE TABLE professor (prof_high_degree VARCHAR, emp_num VARCHAR, dept_code VARCHAR); CREATE TABLE department (dept_code VARCHAR, dept_name VARCHAR); CREATE TABLE employee (emp_fname VARCHAR, emp_num VARCHAR); CREATE TABLE CLASS (prof_num VARCHAR)

Question: Find the first names and degree of all professors who are teaching some class in Computer Info. Systems department.
SQL: SELECT DISTINCT T2.emp_fname, T3.prof_high_degree FROM CLASS AS T1 JOIN employee AS T2 ON T1.prof_num = T2.emp_num JOIN professor AS T3 ON T2.emp_num = T3.emp_num JOIN department AS T4 ON T4.dept_code = T3.dept_code WHERE T4.dept_name = 'Computer Info. Systems'