Database: customers_and_invoices
Question: Return the last name, id and phone number of the customer who has made the greatest number of orders.
SQL:
SELECT T2.customer_last_name ,  T1.customer_id ,  T2.phone_number FROM Orders AS T1 JOIN Customers AS T2 ON T1.customer_id  =  T2.customer_id GROUP BY T1.customer_id ORDER BY count(*) DESC LIMIT 1