Database: college_2

Question: What are the ids of courses offered in Fall of 2009 but not in Spring of 2010?
SQL: SELECT course_id FROM SECTION WHERE semester  =  'Fall' AND YEAR  =  2009 EXCEPT SELECT course_id FROM SECTION WHERE semester  =  'Spring' AND YEAR  =  2010

Question: What are the distinct salaries of all instructors who earned less than the maximum salary?
SQL: SELECT DISTINCT salary FROM instructor WHERE salary  <  (SELECT max(salary) FROM instructor)

Question: How many instructors teach a course in the Spring of 2010?
SQL: SELECT COUNT (DISTINCT ID) FROM teaches WHERE semester  =  'Spring' AND YEAR  =  2010

Question: What are the names and average salaries for departments with average salary higher than 42000?
SQL: SELECT dept_name ,  AVG (salary) FROM instructor GROUP BY dept_name HAVING AVG (salary)  >  42000

Question: What are the names of instructors who earn more than at least one instructor from the Biology department?
SQL: SELECT name FROM instructor WHERE salary  >  (SELECT min(salary) FROM instructor WHERE dept_name  =  'Biology')

Question: What are the names of all instructors with a higher salary than any of the instructors in the Biology department?
SQL: SELECT name FROM instructor WHERE salary  >  (SELECT max(salary) FROM instructor WHERE dept_name  =  'Biology')