SQL — Right Join

Basic RIGHT JOIN

SELECT u.name, o.total
FROM users u
RIGHT JOIN orders o ON u.id = o.user_id;

All orders with users

-- Orders without users will have NULL
SELECT u.name, o.total
FROM users u
RIGHT JOIN orders o ON u.id = o.user_id;

Convert RIGHT to LEFT

-- RIGHT JOIN
SELECT u.name, o.total
FROM users u
RIGHT JOIN orders o ON u.id = o.user_id;

-- Equivalent LEFT JOIN
SELECT u.name, o.total
FROM orders o
LEFT JOIN users u ON o.user_id = u.id;

Find orders without users

SELECT o.*
FROM users u
RIGHT JOIN orders o ON u.id = o.user_id
WHERE u.id IS NULL;

Mini Practice

1. Perform RIGHT JOIN
2. Convert RIGHT to LEFT JOIN
3. Find orphaned records
4. Use with WHERE clause

Up Next

Continue with Subqueries - Sub-queries.