RIGHT JOIN keeps every row from the second table

RIGHT JOIN is LEFT JOIN facing the other way. It keeps every row from the table named second and fills the first table’s columns with NULL when there is no match. So an order with no known customer still shows up, with a blank name. Most people swap the two tables and write a LEFT JOIN instead, because reading left to right is easier — both give the same rows.

SELECT c.name, o.total
FROM customers c
RIGHT JOIN orders o
  ON o.customer_id = c.id;