There is no such

FULL JOIN

in MySQL but we can get the same result using

UNION

SELECT 
    students.*, 
    notes.*
FROM `students` 
LEFT JOIN notes ON notes.student_id = students.id
UNION
SELECT 
    students.*, 
    notes.*
FROM `students` 
RIGHT JOIN notes ON notes.student_id = students.id

As default,

UNION

removes duplicate rows. If we want to get all the rows including duplicates, we can use

UNION ALL

SELECT 
    students.*, 
    notes.*
FROM `students` 
LEFT JOIN notes ON notes.student_id = students.id
UNION ALL
SELECT 
    students.*, 
    notes.*
FROM `students` 
RIGHT JOIN notes ON notes.student_id = students.id

Divides all the students into different classes

SELECT *, 'Brilliant' AS class
FROM `students`
WHERE points >= 90
UNION
SELECT *, 'Gold'
FROM `students`
WHERE points >= 80 
    AND points < 90
UNION
SELECT *, 'Silver'
FROM `students`
WHERE points >= 60 
    AND points < 80
UNION
SELECT *, 'Lazy'
FROM `students`
WHERE points < 60
ORDER BY points DESC