hi arnelgp,
thanks for the help.
i tried to add in more data in the table and there is some error.
1. i keyed in
Buyer table : A1003, AA885 , cost=$100
Shipment table : AA885,shipment amount = $50
Query results: A1003,AA885, $80, 4/5/2019, paid.
Shouldn't be A1003,AA885,$50, 4/5/2019...