silly

          SELECT users.username,
            ((CASE WHEN quizzes.quiz_type = 1 THEN 'M' ELSE 'B' END) ||
            (CASE WHEN user_answers.practical_id IS NULL THEN '' ELSE 'P' END) ||
            quizzes.challenge_number || 'Q' || questions.question_number)
            AS quest,
            SUM(result) As score

          FROM "user_answers"

          INNER JOIN "users" ON "users"."id" = "user_answers"."user_id"
          INNER JOIN "quizzes" ON "quizzes"."id" = "user_answers"."quiz_id"
          INNER JOIN "questions" ON "questions"."id" = "user_answers"."question_id"

          GROUP BY users.username, user_answers.quiz_id, user_answers.practical_id,
            ((CASE WHEN quizzes.quiz_type = 1 THEN 'M' ELSE 'B' END) ||
            (CASE WHEN user_answers.practical_id IS NULL THEN '' ELSE 'P' END) ||
            quizzes.challenge_number || 'Q' || questions.question_number), questions.question_number

          ORDER BY quest