id    qty stuff_id re
P001  100  S00001
P001  200  S00002
P002  3000 S00001
P002  2000 S00002
P003  100  S00001
P003  200  S00002
P003  300  S00003
展开如下:
id    S0001 S0002 S0003
P001  100  200       0
P002  3000  2000     0
P003  100  200     300请大家给点提示?