Copying info from one subform to another form

[Stu Man Do]

Now before we begin I'm a bit of a newbie with Access! I am trying to create a system that allows a book store to store customer details, stock information and create records about orders by using an orders table and an orders details table so that I can link more than one book into one order.

The issue I have is that I have created an orders form with an orders details subform where I have used a combo box to fill in certain fields such as title and price per unit. My first problem is that once I enter a book ID via the drop down list - you cannot then change the book ID if for example you had entered the wrong book UNLESS you delete that record and re-enter.

The second issue I had is that I wanted to be able to show an order history on the customer form based on any records for that customer by the order number and order details table. I had attempted to use the same sub form on the customer form however this just shows all records from the orders table.

Is there any way to do this? Apologies if this is utterly confusing but I have attached my database for people to have a look at if they wouldn't mind!
Thanks!
Stu

[June7]

OrderID field in OrderDetails should not be AutoNumber. This is foreign key field and need to save the OrderID primary key value. Change it to a number (long integer) type. The TransactionID field should be AutoNumber, delete it and recreate or leave it off. It is not needed because OrderDetails does not have child related tables. Will have to remove relationship between Orders and OrderDetails to fix this then re-establish.

Do not include the OrderDetails table in the main form RecordSource.

Do not include the Orders table in the subform RecordSource.

Change the join type of the subform RecordSource from INNER to RIGHT.

[price of each] textbox should be bound to Price. Set Title and Price textboxes properties Locked Yes and TabStop No.

TotalPrice calculation should be: [Quantity] * [Price]. Unit price should not be saved to OrderDetails unless there is a chance the price in the Books table will be changed in the future. In which case, will require VBA code to save the unit price.

Advise no spaces in names.