I have the following queries and results:

1) select filenumber, sum(DB_Amount), sum(CR_Amount)
from ledger where VORP > "" group by filenumber, VORP
having sum(DB_AMOUNT) - sum(CR_AMOUNT) = 0

sample results:
FILENUMBER SUM SUM1
=========== ======== ========
8552 15 15
29450 3756.94 3756.94
29657 920.19 920.19
29863 100 100
29956 19000 19000
29958 1518 1518
29970 100 100
30532 3000 3000

2) select filenumber, sum(DB_Amount), sum(CR_Amount)
from ledger where VORP > "" group by filenumber, VORP
having sum(DB_AMOUNT) - sum(CR_AMOUNT) <> 0

sample results:
FILENUMBER SUM SUM1
=========== ======== ========
26062 2926 4646
29933 7717.48 7717.48
30190 14476.03 14476.03
30473 533.48 533.48
30497 3323.7 3323.7
30525 1184.41 1184.41
30529 1262.88 1262.88

Both results were not meeting the expectation. The selection from
result 1) does not return filenumber 29933, but the selection from
result 2) includes those = 0.

Is there a problem in my SQL using the SUM function?

Please help.

Thanks
Duncan