InfoPath Dev

I have two Query Fields in my form. The first is populated by the user via a drop down box. The second i want the user to either enter information or leave blank. However, if they leave this blank, I actually want the data returned to be blank (or null) for that field. Right now if I leave it blank, it return everything. I'm only looking ...

I have a situation where we have 90 clients that we send invoices to. All other clients (about 80) have to pre-pay. I need to have a rule where depending on the client number, an option appears giving the user the option of sending an invoice, but only for the 90 clients who have that option. For the remaining 80 clients, that option should not ...

I have an append query in Access that needs to run prior to a user filling out a form. Is there a way to have that user click a button on the form or have the code run on open of the form that will run the append query within Access? Thanks, K13