นานแค่ไหนแล้วที่โรงเรียนเริ่มจำหน่าย MACROMOL 995 ?ไม่จำเป็นต้องใช้ทุกโต๊ะเลย
How long has it been since the school started offering MACROMOL 995 ?It is not neccessary to use all the tables.
 program_course:  program_id [ int]  course_id [ int]  workload [ int]  category [ varchar] 
SELECT DISTINCT semester.year FROM course, course_offering, semester WHERE course.course_id = course_offering.course_id AND course.department = 'MACROMOL' AND course.number = 995 AND semester.semester_id = course_offering.semester ORDER BY semester.year LIMIT 1