
SELECT
user.firstname AS Firstname,
user.lastname AS Lastname,
user.email AS Email,
course.fullname AS Course
FROM mdl_course AS course
JOIN mdl_enrol AS en ON en.courseid = course.id
JOIN mdl_user_enrolments AS ue ON ue.enrolid = en.id
JOIN mdl_user AS user ON ue.userid = user.id