นับสินค้าที่มีคำอธิบายสี "สีขาว" หรือมีลักษณะชื่อ "ร้อน" ไม่จำเป็นต้องใช้ทุกตาราง
Count the products that have the color description "white" or have the characteristic name "hot".It is not neccessary to use all the tables.
 CHARACTERISTICS:  (characteristic_id [ VARCHAR ] characteristic_name [ VARCHAR) ]
SELECT COUNT(*) FROM products AS t1 JOIN product_characteristics AS t2 ON t1.product_id = t2.product_id JOIN CHARACTERISTICS AS t3 ON t2.characteristic_id = t3.characteristic_id JOIN ref_colors AS t4 ON t1.color_code = t4.color_code WHERE t4.color_description = "white" OR t3.characteristic_name = "hot"