That would be lovely.
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 group by t1.customer_name order by sum ( t3.order_quantity ) desc limit 1
How many did he purchase?
select sum ( t3.order_quantity ) 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 group by t1.customer_name order by sum ( t3.order_quantity ) desc limit 1
How did he pay?
select t1.payment_method 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 group by t1.customer_name order by sum ( t3.order_quantity ) desc limit 1
When did he become a customer?
select t1.date_became_customer 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 group by t1.customer_name order by sum ( t3.order_quantity ) desc limit 1
How many became customers before that?
select count ( * ) from customers where date_became_customer < ( select t1.date_became_customer 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 group by t1.customer_name order by sum ( t3.order_quantity ) desc limit 1 )