What is the total quantity of products purchased by "Rodrick Heaney"?
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"
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"
[{'sum(t3.order_quantity)': 21}]