What is the largest order quantity listed in the database?
select max(order_quantity) from order_items
What is the name of the customer who made that order?
select t1.customer_name from customers as t1 join customer_orders as t2 on t1.customer_id = t2.customer_id join order_items as t3 on t2.order_id = t3.order_id where t3.order_quantity = ( select max(order_quantity) from order_items)