CREATE DEFINER = `your_user`@`%` PROCEDURE `RemoveUserDataFromCourse`(IN `c_id` int,IN `u_id` int)
BEGIN
    # ENROLLMENT
    DELETE FROM mdl_user_enrolments WHERE userid = u_id AND enrolid IN (SELECT id FROM mdl_enrol WHERE courseid = c_id);

  # LOG, EVENT, POSTS
    DELETE FROM mdl_log WHERE course = c_id AND userid = u_id;
    DELETE FROM mdl_event WHERE courseid = c_id AND userid = u_id;
    DELETE FROM mdl_post WHERE courseid = c_id AND userid = u_id;

    # Course completion
    DELETE FROM mdl_course_modules_completion WHERE coursemoduleid IN (SELECT id FROM mdl_course_modules WHERE course= c_id and userid=u_id);
    DELETE FROM mdl_course_completions WHERE course = c_id AND userid = u_id;
    DELETE FROM mdl_course_completion_crit_compl WHERE course = c_id AND userid = u_id;

    # Grades from all modules
    DELETE FROM mdl_grade_grades WHERE userid = u_id and itemid IN (SELECT id FROM mdl_grade_items WHERE courseid = c_id);

    # MODULES

    # ASSIGNMENTS
    DELETE FROM mdl_assign_grades WHERE userid = u_id AND assignment IN (SELECT id FROM mdl_assign WHERE course = c_id);    

    # QUIZ
    DELETE FROM mdl_quiz_attempts WHERE userid = u_id AND quiz IN (SELECT id FROM mdl_quiz WHERE course = c_id);
    DELETE FROM mdl_quiz_grades WHERE userid = u_id AND quiz IN (SELECT id FROM mdl_quiz WHERE course = c_id);

    # SCORM
    DELETE FROM mdl_scorm_scoes_track WHERE userid = u_id AND scormid IN (SELECT id FROM mdl_scorm WHERE course = c_id);

    # CHECK LIST
    DELETE FROM mdl_checklist_check WHERE userid = u_id AND item IN ( SELECT mci.id FROM mdl_checklist mc INNER JOIN mdl_checklist_item mci ON mci.checklist = mc.id WHERE course = c_id );
    DELETE FROM mdl_checklist_comment WHERE userid = u_id AND itemid IN ( SELECT mci.id FROM mdl_checklist mc INNER JOIN mdl_checklist_item mci ON mci.checklist = mc.id WHERE course = c_id );

    # CHOICE
    DELETE FROM mdl_choice_answers WHERE userid = u_id AND choiceid IN (SELECT id FROM mdl_choice WHERE course = c_id);
END;

SELECT c.fullname
FROM mdl_course c 
JOIN mdl_enrol en ON en.courseid = c.id 
JOIN mdl_user_enrolments ue ON ue.enrolid = en.id 
WHERE ue.userid = '788'

SELECT cr.SHORTNAME, 
       cr.FULLNAME, 
       COUNT(ra.ID) AS enrolled 
FROM   MDL_COURSE cr 
       JOIN MDL_CONTEXT ct 
         ON ( ct.INSTANCEID = cr.ID ) 
       LEFT JOIN MDL_ROLE_ASSIGNMENTS ra 
              ON ( ra.CONTEXTID = ct.ID ) 
WHERE  ct.CONTEXTLEVEL = 50 
       AND ra.ROLEID = 5 
GROUP  BY cr.SHORTNAME, 
          cr.FULLNAME 
ORDER  BY ENROLLED ASC 

https://docs.moodle.org/36/en/ad-hoc_contributed_reports

select mc.shortname as course_Id,mu.username, 
case when ABS(ROUND(mgg.finalgrade, 0) - mgg.finalgrade) <= 0.0000005 then cast(mgg.finalgrade as text) else 'Pending...' end as final_grade,
mgi.itemname
from mdl_grade_grades mgg
join mdl_user mu on mgg.userid=mu.id
join mdl_user_enrolments mue on mue.userid=mu.id
join mdl_grade_items mgi on mgg.itemid=mgi.id
join mdl_course mc on mc.id=mgi.courseid
join mdl_enrol me on mue.enrolid=me.id and me.courseid=mc.id
join mdl_role_assignments mra on mu.id=mra.userid
join mdl_role mr on mra.roleid=mr.id
where mc.category = '1' and -- mdl_course_categories.id = '1'; id=1 => name='Spring 2012' as an example 
mr.shortname='student' and -- only get people enrolled with a 'student' role in the course
mgi.itemname ilike '%Final%Grade%'; --anything with 'final' and 'grade' in it regardless of case and surrounding text