What is the full name of the customer who rented the highest number of movies of all time?
full name refers to first_name, last_name; customer who rented the most film refers to Max(count(rental_id))
SELECT T.first_name, T.last_name FROM ( SELECT T2.first_name, T2.last_name, COUNT(T1.rental_id) AS num FROM rental AS T1 INNER JOIN customer AS T2 ON T1.customer_id = T2.customer_id GROUP BY T2.first_name, T2.last_name ) AS T ORDER BY T.num DESC LIMIT 1