จำนวนผลิตภัณฑ์ทั้งหมดที่ซื้อโดย "Rodrick Heaney" คือเท่าใด?ไม่จำเป็นต้องใช้ตารางทั้งหมด
What is the total quantity of products purchased by "Rodrick Heaney"?It is not neccessary to use all the tables.
 customers:  (customer_id [ VARCHAR ] customer_name [ VARCHAR) ]
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 WHERE t1.customer_name = "Rodrick Heaney"