SELECT s.name, l.day_of_the_week, t.test_name FROM subject s
                                                INNER JOIN lesson l ON s.id_subject = l.id_subject
                                                LEFT JOIN test t ON t.id_lesson = l.id_lesson
                                                INNER JOIN lesson_user lu ON lu.id_lesson = l.id_lesson
                                                INNER JOIN user u ON lu.id_user = u.id_user AND u.login = 'ala'



name            day_of_the_week         test_name
Język polski   pon-10:45               Testowy test
Matematyka      wt-11:20                NULL
Język polski   śr-12:10               Nowy test