'ฐานข้อมูล' ของรายวิชามีคำอธิบายอะไรบ้าง?ไม่จำเป็นต้องใช้ตารางทั้งหมด
What are the descriptions of the courses with name 'database'?It is not neccessary to use all the tables.
 students:  student_id [ number]  date_of_registration [ time]  date_of_latest_logon [ time]  login_name [ text]  password [ text]  personal_name [ text]  middle_name [ text]  family_name [ text] 
SELECT course_description FROM courses WHERE course_name = "database"