表A id datetime pay(收入表)
表B id Bdatetime pay(支出表)
A:
1 2012-08-19 22.00
2 2012-09-23 32.00
3 2012-09-30 33.00
B:
1 2012-08-20 -11.00
2 2012-09-24 -20.00
输出:
C:(id Cdatetime pay paycount)
1 2012-08-19 22.00 22.00
2 2012-08-20 -11.00 11.00
3 2012-09-23 32.00 43.00
4 2012-09-24 -20.00 23.00