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Customers who never order

EasyP1Coding

Tables:

customers

Column	Type
id	int (primary key)
name	text

orders

Column	Type
id	int (primary key)
customer_id	int (references customers.id)

Write a query that returns the names of customers who have never placed an order. Return one column named customer.

Schema

CREATE TABLE customers (
  id int PRIMARY KEY,
  name text NOT NULL
);
CREATE TABLE orders (
  id int PRIMARY KEY,
  customer_id int NOT NULL REFERENCES customers(id)
);

Example 1

Input: customers: (1, 'Ann'), (2, 'Bob') orders: (10, 1)
Output: customer: Bob

Constraints

PostgreSQL dialect.
A customer can have many orders.
Return rows in any order.

Hints

PostgreSQL

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