[mySQL] solvesql 오스트리아 고객들의 환불 금액

Q. https://solvesql.com/problems/refund-austria/

SELECT ABS(SUM(price * quantity)) AS refund_austria
FROM order_items LEFT JOIN orders ON order_items.order_id = orders.order_id
                 LEFT JOIN customers ON orders.customer_id = customers.customer_id
WHERE order_items.order_id LIKE 'C%'
AND country = 'Austria'

☑️ point

• ABS( ) -> 절대값 반환