Invoice Payment Query

[Declan Barry]

Hi all..

I have a query from one of our students regarding an order invoice
payment database. The student can make up the order database okay
where a customer picks a number of products and enters the quantity
and then the system prints out an invoice for the customer which
he/she can then pay.

The twist in this one is, rather than the customer paying the invoice
in full, the student wants the customer to have the ability to pay off
small amounts of the outstanding bill and only when it reaches zero
can the customer raise another order.

The teacher who is getting to grips with access and is quite good, is
slightly stumped. She is trying to update a customer balance field in
Cust table with a value that has been calculated in a multitable
query. She has used the Sum function to work out the total order cost
for each customer who has ordered several items in a query and now
wants to put that calculated value into the customer table - customer
balance field. The error message she gets is "operation must use an
updateable query". She has also tried an append query but it doesn't
work either.

Anyone any ideas or samples that I(we) can look at?

Regards

Declan

[pietlinden]

if you have a child table "InvoicePayments", then when the sum of a
total due minus the invoice's payments, then you can allow more
invoices to be created.