ASTRO 389 มีกี่ส่วน ?ไม่จำเป็นต้องใช้ตารางทั้งหมด
Of ASTRO 389 , how many sections are there ?It is not neccessary to use all the tables.
 offering_instructor:  offering_instructor_id [ int]  offering_id [ int]  instructor_id [ int] 
SELECT COUNT(*) FROM course, course_offering, semester WHERE course.course_id = course_offering.course_id AND course.department = 'ASTRO' AND course.number = 389 AND semester.semester = 'WN' AND semester.semester_id = course_offering.semester AND semester.year = 2016