SELECT mk_users.id as user_id, mk_users.mail as user_mail, mk_user_course_info.course_id, mk_courses.name, mk_user_course_info.course_progress,
(SELECT sum(mk_int_score.score) / count(*) from mk_int_score WHERE mk_int_score.user_id = mk_users.id AND mk_int_score.course_id = mk_user_course_info.course_id) as course_poprawnosc
FROM mk_users
JOIN mk_user_course_info ON mk_users.id = mk_user_course_info.user_id
JOIN mk_courses ON mk_user_course_info.course_id = mk_courses.id
JOIN mk_int_score ON mk_users.id = mk_int_score.user_id
WHERE mk_users.mail LIKE '%@metro-advertising.pl%'
OR mk_users.mail IN ('kdenisar@wp.pl', 'nalikowskiar@wp.pl', 'rydzenskiar@wp.pl', 'diduchpar@wp.pl', 'organiakar@wp.pl', 'szczesnyar@wp.pl', 'michalczukar@wp.pl', 'kajdasar@wp.pl', 'mikolajczykakarat@wp.pl', 'pleskotakarat@wp.pl')
GROUP BY course_id
ORDER BY user_id ASC;