What are the names of the customers who have made two or less orders?
SELECT T2.customer_name FROM orders AS T1 JOIN customers AS T2 ON T1.customer_id = T2.customer_id GROUP BY T2.customer_id HAVING count(*)  <=  2
SELECT T2.customer_name FROM orders AS T1 JOIN customers AS T2 ON T1.customer_id = T2.customer_id GROUP BY T2.customer_id HAVING count(*)  <=  2
[{'customer_name': 'Alberto'}, {'customer_name': 'Leilani'}, {'customer_name': 'Hadley'}, {'customer_name': 'Violet'}, {'customer_name': 'Parker'}, {'customer_name': 'Devan'}, {'customer_name': 'Beulah'}, {'customer_name': 'Hershel'}]