Left Join Missing

-- Drill 12 — LEFT JOIN لاكتشاف العملاء بلا طلبات — SQLite 3.x+
PRAGMA foreign_keys = ON;

CREATE TABLE customers (
  id INTEGER PRIMARY KEY,
  name TEXT NOT NULL
);

CREATE TABLE orders (
  id INTEGER PRIMARY KEY,
  customer_id INTEGER NOT NULL REFERENCES customers(id)
);

INSERT INTO customers VALUES
  (1, 'Sara'),
  (2, 'Noura');

INSERT INTO orders VALUES (10, 1);

SELECT customers.name
FROM customers
LEFT JOIN orders
  ON orders.customer_id = customers.id
WHERE orders.id IS NULL;