Lin gaoyuan wu jiaji เล่นชายคู่กี่ปี?ไม่จำเป็นต้องใช้โต๊ะทั้งหมด
How many years did lin gaoyuan wu jiaji play  mens doubles?It is not neccessary to use all the tables.
 table_28138035_20:  (year_location [ VARCHAR ] mens_doubles [ VARCHAR) ]
SELECT COUNT(year_location) FROM table_28138035_20 WHERE mens_doubles = "Lin Gaoyuan Wu Jiaji"