Dsum (Not appear correct calculation)

[sbaig2]

first of all sorry to my poor English

I have subform of inventry Transaction there are field productId, UnitsSale, SalePrice

I am using combo box on productId and want to calculate When i change productId (Stock in hand to show on msgbox) for the productId which i choosen from combo box


if any one know about it please help


Baig

 

[RuralGuy]

Maybe this link will help. Inventory Control: Quantity on Hand