581 มีขนาดใหญ่แค่ไหน ?ไม่จำเป็นต้องใช้ทุกตาราง
Exactly how big is 581 ?It is not neccessary to use all the tables.
 program_requirement:  program_id [ int]  category [ varchar]  min_credit [ int]  additional_req [ varchar] 
SELECT DISTINCT num_enrolled FROM course WHERE department = 'EECS' AND number = 581