[AccessD] What is the cost

Does anyone know the cost of building a base query, then a query on top of that query with a where 
clause in the top query.

And is there any other way to do this...

I need to build a boolean true / false in two fields FieldA and FieldB, then a third field - Where 
not FieldA and Not FieldB.

Trying to do this directly in one query gives an error message "does not recognize FieldA".  In the 
past I always just built a "base query" where I build up the boolean fields FieldA and FieldB, then 
create a query on top of that which does the final where not fielda and not fieldb.

this does work because FieldA and FieldB now exist to the top level query, but of course it causes 
me to have to create two queries etc.

Can this be done in a single level?  In theory you could put whatever you are doing to create the 
boolean values into a single field, but it is not "visible", i.e. you cannot look down through the 
data and SEE whether the records create boolean trues and falses.

So I want to create the two boolean fields, and then use those fields in a third field.  ATM Jet is 
objecting.

-- 
John W. Colby
www.ColbyConsulting.com