Subqueries vs Joins

What You Will Learn

• JOINs are often easier to optimize for relational lookups.
• Subqueries can improve readability for isolated logic blocks.
• Always compare execution plans for complex queries.

Sample SQL

SELECT u.id, u.name
FROM users u
WHERE u.id IN (
  SELECT o.user_id
  FROM orders o
  WHERE o.status = 'paid'
);

Next Step

Try rewriting this query in your own schema, then use our tools to format and refine it.