Microsoft Access 2010 Creating a Form from Multiple Tables

Question

Hi.
I am brand new to Microsoft Access and have had some exciting success making forms from single tables. This has made my data entry life much easier. However, I am continually stumped on one form I want to make. I would like to make a form that will let me
update which brands retailers are selling. Most of this information is in my SalesHx table. However, my SalesHx table only uses RetailerID and BrandID to record history. The Brand's name (linked to a BrandID) is stored in my Brand Table and the Retailer name
is stored in my Retailer table (linked to a RetailerID). I would like to be able to see the brand's name and the retailer's name when entering in data on a form, since I cannot remember the ids that associate with the names. I have been able to make a form,
with a subform, that displays all of the information I want to see. When I update this form, though, with a new record, it invariably thinks that I am adding an entirely new record, not simply recording a new sales date for an already known brand. Even if
I make the brand name a combo box that is limited to the fields on my table, this still happens. I will have BrandX as brand number 100 and as brand number 300 if I add it in through my sales history form. I am ready to throw access out the window. Can anyone
offer advice?

Answer 1

 When I update this form, though, with a new record, it invariably thinks that I am adding an entirely new record, not
simply recording a new sales date for an already known brand. 
In what table is the SalesDate recorded?
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