Subtracting Fields

[zakslaher]

hi Guys

i have the following fields: Quantity, Quantity received, Total Quantity.


quantity - quantity received is the new total quantity. total quantity must not be greater than original quantity entered and cannot equal 0. quantity received can not be greater then original quantity.

[RuralGuy]

Calculations do not belong in tables but in queries or forms.

[zakslaher]

help please

[RuralGuy]

Have you designed the form that will make the change?

[zakslaher]

yes i have created the form.
i have the following on the form:
waybill number:
quantity:
quantity received:
quantity available:

when opening the form the user is prompted for the waybill number. waybill number is entered and the quantity for that waybill is automatically filled in.
the user then enters the quantity received, quantity available = quantity - quantity received. however, quantity available cannot = 0 and quantity received cannot exceed the original quantity

[RuralGuy]

Did you create a table for the form?

[zakslaher]

yes, table created

[RuralGuy]

So you can not enter the Quantity Received = Quantity Right? Why not?

[zakslaher]

correct, the user will be entering the quantity received as and when he receives the stock. and thats why i thought of having the quantity available - this will show the user how much is available once the qty was received and the original quantity will not change.i managed to subtract and getthe results but when i go back to that waybill to subtract more stock then the numbers dont add, it is subtracting from original quantity all the time.

[RuralGuy]

You lost me. Inventory is a dynamic number and should be calculated each time you need to use it.

[zakslaher]

this is what i am doing, maybe you can advise on a better solution.
we receive waybills from RAM. each waybill will have x amount of goods A. i created a table and form with import the excel sheet received into the table. all the sheet will contain in the waybill number, the model and the quantity.
the user then wants to be able to amend the quantity as and when the stock arrives. he also wants to be able to see how much of stock is outstanding on a particular waybill number.

[RuralGuy]

See if this link makes any sense. http://allenbrowne.com/AppInventory.html

[zakslaher]

thanks,

however i must be honest but now im lost forever.

[RuralGuy]

Isn't the Quantity you keep mentioning actually an inventory somewhere?

[zakslaher]

yes, is it possible for me to email you the db, so you can see what i did.
we jsut need to account for what was said to be received and what actually was received.