CREATE TABLE time_slot (time_slot_id TEXT, day TEXT, start_hr DECIMAL, start_min DECIMAL, end_hr DECIMAL, end_min DECIMAL)
CREATE TABLE takes (id TEXT, course_id TEXT, sec_id TEXT, semester TEXT, year DECIMAL, grade TEXT)
CREATE TABLE advisor (s_id TEXT, i_id TEXT)
CREATE TABLE course (course_id TEXT, title TEXT, dept_name TEXT, credits DECIMAL)
CREATE TABLE teaches (id TEXT, course_id TEXT, sec_id TEXT, semester TEXT, year DECIMAL)
CREATE TABLE student (id TEXT, name TEXT, dept_name TEXT, tot_cred DECIMAL)
CREATE TABLE prereq (course_id TEXT, prereq_id TEXT)
CREATE TABLE instructor (id TEXT, name TEXT, dept_name TEXT, salary DECIMAL)
CREATE TABLE section (course_id TEXT, sec_id TEXT, semester TEXT, year DECIMAL, building TEXT, room_number TEXT, time_slot_id TEXT)
CREATE TABLE classroom (building TEXT, room_number TEXT, capacity DECIMAL)
CREATE TABLE department (dept_name TEXT, building TEXT, budget DECIMAL)

Find courses that ran in Fall 2009 but not in Spring 2010.
SELECT course_id FROM section WHERE semester = 'Fall' AND year = 2009 EXCEPT SELECT course_id FROM section WHERE semester = 'Spring' AND year = 2010
SELECT "course_id" FROM "section" WHERE "semester" = 'Fall' AND "year" = 2009 EXCEPT SELECT "course_id" FROM "section" WHERE "semester" = 'Spring' AND "year" = 2010