London Marathon จัดขึ้นที่ไหน?ไม่จำเป็นต้องใช้โต๊ะทั้งหมด
Where was the London Marathon held?It is not neccessary to use all the tables.
 table_name_19:  (venue [ VARCHAR ] event [ VARCHAR ] competition [ VARCHAR) ]
SELECT venue FROM table_name_19 WHERE event = "marathon" AND competition = "london marathon"