Store Calculations

Ok I know everyone is going to say you should not store calculations, but I have no choice!!!!!!!!!! I have the form ORDERFORM (recordsource ORDERS table) with a subform ORDERFORMsubPROD (recordsource ORDERSPROD table). Essently theses 2 forms togather allow me to place an order for multiple products and store them in the ORDERS (key: ORDERID) and ORDERSPROD (foregin key: ORDERID) tables. The ORDERFORM includes information such as an ORDERDT and the ORDERFORMsubPROD includes a sum of cost the products ordered which is shown in ORDERFORM with a boundcontrol = to the ORDERFORMsubPROD control that does the actual calculations.

Next I need to be able to pull specific informtaion from the ORDERS table and group it togather by the SALESMANID. To this end I have a form SALESMAN with a subform SALESMANsubORDERS that displayes the ORDERID, ORDERDT, and the calculated sum of the products ordered on that ORDERID based on the SALESMANID of the order.

So far everything stated above is correct and should not require that I store calculations. My problem comes in when I am trying to make a form that will filter this information based on user supplied criteria (my user does not want to have to use the filer buttions supplied by Access). I'm using DoCmd.OpenForm and setting my WHERE criteria based on a bunch of If .. Then statements that check the various filter text/combo boxes to determine if they are populated and then admend the WHERE statement accordingly. At least that is how it works on a very similar form that filters ORDERFORM. I have discovered that because the subform, SALESMANsubORDERS, is based on a query that includes calculations the WHERE statement needs to be phrased as HAVING. I can not figure out how to get Access to comply with this so all I can think of is to store the calculated values (and be able to allow them to be updated later) then pull them directly from the ORDERS table.

Anyone who can write precise/generic code and most importantly tell me where (what event) that code should be placed on please let me know. This is the first time I have run into this problem and it is really my last problem before completing a DB application that needs to be completed by Wed 1/19/2005. Thanks in advance for any advise/help I receive.