Combo box values for existing and new records

[ciruliz]

Hello,
I don't really know how to formulate question, so I will try to
explain problem shortly:
I have created small invoicing application in Access 2007 for renting
business - there is table of customers, table of invoices and table of
devices we offer for rent (there is one type of devices, total number
- around 10)
There is form for entering new customers and that form contains combo
box, which is lookup to devices table - so user can pick one of
devices.
Everything works so far.
I wanted to introduce new feature - when adding new customer, user can
choose only from those devices which are not rented away. So I created
subquery to limit values of combo box.
Query looks like this:

SELECT Koncentratori.ID, Koncentratori.AccountingNumber 
FROM Koncentratori 
WHERE (((Koncentratori.ID) Not In (SELECT customers.ConcentratorID 
FROM customers WHERE (((customers.agreementActive)=Yes)); ))) 
ORDER BY Koncentratori.AccountingNumber;

Koncentratori (Concentrators) is the mentioned table of devices, rest
should be obvious.
So far so good.
But here comes the problem - after using this subquery, new record can
be added nicely and combo box contains only those devices, which are
not rented away. However for existing customers combo box does not
show current value - as it is in conflict with that subquery.


I am not sure how to overcome this problem, thanks for any advice!
Br,
Andis

[TheShabz]

My first thought is to create an "isAvailable" field in your Device table.
Use whatever method you want to indicate it (yes/no, -1/0, whatever).
Apply this to Devices already in use.
Have your combox query be SELECT DeviceName FROM Device WHERE isAvailable = yes
When a customer is created, have an update query run to set the isAvailable for that Device to 'no'.
Requery your Form.

I think that should fix your subquery conflict.