MySQL Transpose

Before

NAME	Subject	Grade
Den	History	A
River	History	B
Paris	History	C
River	Math	A
Den	Math	B
Jay	Math	C

SELECT
      Subject,
      MAX(IF(Grade = 'A', Name, NULL)) AS A,
      MAX(IF(Grade = 'B', Name, NULL)) AS B,
      MAX(IF(Grade = 'C', Name, NULL)) AS C,
FROM TABLE
GROUP BY Subject;

After

Subject	A	B	C
History	Den	River	Paris
Math	River	Den	Jay

 

어렵게 생각하다가 시간을 많이 썼다..