>Is there a way to dynamically change the number of parameters passed to a view in VFP at the time of requery?
>(like building the where clause at run time)

This is a feature of Visual FoxExpress called "dynamic view parameters." Great stuff!

http://www.f1tech.com/VFE/

View parameters that are left empty are not added to the where clause when the view is requeried. Data dictionary properties allow you control behaviors (add with AND, add with OR, Negate, Omit when Null, Always Omit, etc). See the following link...

http://www.f1tech.com/VFE/whatsnewinvfe2005.asp

You get the source for how this works when you purchase the framework.