Input
------------------------------------------------------
SALES-NUM | SALESMAN-ID | PROFIT
------------------------------------------------------
1 | 1 |+500
2 | 1 |+300
3 | 1 |-700
1 | 2 |-200
2 | 2 |-300
1 | 3 |-200
2 | 3 |+400
Output
-----------------------------------------------------
SALES-NUM | SALESMAN-ID |PROFIT
-----------------------------------------------------
2 | 1 | 300
2 | 2 |0
2 |3 | 400
------------------------------------------------------
SALES-NUM | SALESMAN-ID | PROFIT
------------------------------------------------------
1 | 1 |+500
2 | 1 |+300
3 | 1 |-700
1 | 2 |-200
2 | 2 |-300
1 | 3 |-200
2 | 3 |+400
Output
-----------------------------------------------------
SALES-NUM | SALESMAN-ID |PROFIT
-----------------------------------------------------
2 | 1 | 300
2 | 2 |0
2 |3 | 400
What it does is
- Fetches one row for each salesman
- Profit should be most current positive numeric or zero .