คำถามที่ให้คะแนนสูงสุดโดยผู้ใช้ครั้งเดียว ไม่จำเป็นต้องใช้ตารางทั้งหมด
Highest Scoring Questions by One Time User.It is not neccessary to use all the tables.
 PostTypes:  Id [ number]  Name [ text] 
SELECT * FROM Users AS u WHERE Id IN (SELECT p.OwnerUserId FROM Posts AS p WHERE p.OwnerUserId IN (SELECT Id FROM Users AS u WHERE Reputation > 20000) GROUP BY p.OwnerUserId HAVING (COUNT(*) = 1))