LeetCode1280.SQL

select s.student_id as student_id, s.student_name as student_name, sub.subject_name as subject_name, count(e.student_id) as attended_exams from Students s cross join Subjects sub left join Examinations e on s.student_id = e.student_id and sub.subject_name = e.subject_name group by s.student_id, sub.subject_name order by s.student_id, sub.subject_name;