Stock on hand calculation

[KerryBara]

Hello,

I am currently designing a stores management database similar to the Northwind database but alot less complicated. We dont need all stock price,sales price and order information. The objective of my database is to calculate stock on hand and have a alert if current stock levels are below a reorder level.

I have taken a begginers course on access and so far so good. Got my relationships sported and everything is working nicely apart from the stock on hand calculation.

What I have is a products form and inventory movement subform. I have a one to many relationship between the two and when you scroll through the products, the inventory movement is updated too. Great.

But now for the stock on hand calculation. I have inserted a formula into the header of the subform and it works fine, but when I do the same calculation on the form I either get a result that doesnt scroll over with each product or I get a #Error.

I'm stuck and have been working on this for a few weeks, if someone could help that would be great.

Thank you,
Kerry.
PS: see attached for description of relationships

 

[RuralGuy]

Here's a link you might find useful. Inventory Control: Quantity on Hand

 

[KerryBara]

Thanks for that, the problem I was having was with the "control source". Still not really sure what the difference is but it seems to be working now. What I have done is set the formula in the header of the subform as a "default value", and the formula on the form equal to the first but as a "control source".

As you can see I haven't quite grasped the difference between all the differenbt types of data. From the help function I could gather that the "control source" info reflects data from your database/query as well as records data in your database. Im my case I dont want to record the result, I only want it reflected on the form so is this a conflict I should be concerned about? Seems to be working fine.

Thanks in advance.
Kerry

 

[stock-man]

can you update how your problem may have solved