Context: CREATE TABLE Courses (course_name VARCHAR, course_id VARCHAR); CREATE TABLE Student_Enrolment_Courses (course_id VARCHAR)
Question: What's the name of the course with most number of enrollments?
Answer: SELECT T1.course_name FROM Courses AS T1 JOIN Student_Enrolment_Courses AS T2 ON T1.course_id = T2.course_id GROUP BY T1.course_name ORDER BY COUNT(*) DESC LIMIT 1