during a month, display the infor each date, order by date, but this infor is empty in some day. how can i still display each day as a row?
Product date
-----------------
20 2008-01-01
10 2008-01-02
20 2008-01-03
10 2008-01-05
09 2008-01-08
30 2008-01-09
result:
Product date
-----------------
20 2008-01-01
10 2008-01-02
20 2008-01-03
0 2008-01-04
10 2008-01-05
0 2008-01-06
0 2008-01-07
09 2008-01-08
30 2008-01-09