หลักสูตรใดบ้างที่เปิดเฉพาะช่วงฤดูใบไม้ผลิ ?ไม่จำเป็นต้องใช้ตารางทั้งหมด
Which courses are only available during Spring ?It is not neccessary to use all the tables.
 gsi:  course_offering_id [ int]  student_id [ int] 
SELECT DISTINCT course.department, course.name, course.number FROM course INNER JOIN course_offering ON course.course_id = course_offering.course_id INNER JOIN semester ON semester.semester_id = course_offering.semester WHERE course.department = 'EECS' AND semester.semester = 'Spring' AND (SELECT COUNT(DISTINCT SEMESTERalias1.semester) FROM course AS COURSEalias1 INNER JOIN course_offering ON COURSEalias1.course_id = course_offering.course_id INNER JOIN semester AS SEMESTERalias1 ON SEMESTERalias1.semester_id = course_offering.semester WHERE course.course_id = COURSEalias1.course_id) = 1