Postgres 10

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CREATE TABLE customer(customer_id INT, last_name TEXT)
CREATE TABLE payment(payment_id INT,customer_id INT, amount DECIMAL(10,4))
SELECT
  customer_id,
  last_name,
  amount
FROM customer
INNER JOIN payment ON customer.customer_id = payment.customer_id
ERROR:  column reference "customer_id" is ambiguous
LINE 2:   customer_id,
          ^


SELECT
  customer_id,
  last_name,
  amount
FROM customer
JOIN payment USING(customer_id)