Updating Quantity

[muizsyed]

Firstly, im sorry if this might be in the wrong forum, i dont know which one to ask in.

I have a database which has the a products table that contains a ProductID, name, price, stockquantity

i have a invoice form, that contains a subform. The form has the invoice information such as, orderID, customerID, total price
the subform has OrderID (foreignkey), productID, name, price, quantity bought.

The subform is in datasheet view

Using a situation, I add a product, along with quantity,
now i add a second product along with quantity...

how would i be able to take this quantity...away from the quantity (in the products table) for a new quantity to be updated into the products table? seeing as there are more than one product

if u dont understand the situation i can send the database to you

please let me know, thank you

 

[Rich]

Not a good idea to store quantity on hand, this site should help
http://users.bigpond.net.au/abrowne1/AppInventory.html

 

[muizsyed]

thanks, ive got another question, if u dont mind,
ive got a form with a subform that is viewable datasheet view

if i add many products...how would i count the number of rows in the datasheet?

thank you

 

[Rich]

Here's an examp

 

[macsta]

count

I have been looking for an easy way to do that for months you are a Star



Mac

 

[muizsyed]

wow! thank you very much rich, i didnt use the on hand method, but used an update query using a loop to get the items, and on close, top update the stock information. That way i dont get any problems in change of quantity, or change in product. It works! so thank you, rich