SELECT * from users
    join quiz_result qr on users.user_id = qr.user_id
    left join quiz_result qr1 on qr1.user_id = qr.user_id and qr.quiz_result < qr1.quiz_result
where qr1.user_id is null and qr.quiz_id = 1;


select * from users join quiz_result qr on users.user_id = qr.user_id where quiz_id = 1;