Part 72: Subqueries in WHERE: IN, ANY, SOME & ALL

Testing conditions against dynamic subquery lists.

1. The IN Subquery

SELECT name FROM customers 
WHERE id IN (
  SELECT customer_id FROM orders WHERE total_amount > 500
);

2. The ALL and ANY Operators

-- Salary greater than ALL salaries in Marketing:
SELECT first_name, salary FROM employees 
WHERE salary > ALL (
  SELECT salary FROM employees WHERE department = 'Marketing'
);

Key Takeaways

• > ALL means greater than the maximum value in the subquery.
• > ANY means greater than at least one value (the minimum).

In Part 73, we explore Correlated Subqueries: Row-by-Row Evaluation Mechanics!