แสดงชื่อเกมที่มีจำนวนชั่วโมงเล่นมากที่สุด ไม่จำเป็นต้องใช้ทุกโต๊ะ
Show the game name that has most number of hours played.It is not neccessary to use all the tables.
 plays_games:  stuid [ number]  gameid [ number]  hours_played [ number] 
SELECT gname FROM plays_games AS T1 JOIN video_games AS T2 ON T1.gameid = T2.gameid GROUP BY T1.gameid ORDER BY SUM(hours_played) DESC LIMIT 1