Database: student_assessment
Question: How many registed students do each course have? List course name and the number of their registered students?
SQL: select t3.course_name ,  count(*) from students as t1 join student_course_registrations as t2 on t1.student_id = t2.student_id join courses as t3 on t2.course_id = t3.course_id group by t2.course_id