PHP Update Object updates all fields

NetObjects Fusion 9 is probably one of the easiest, most powerful web design 
software packages for simple to complicated sites. However, it seems to be 
seriously lacking in the documentation area. Especially in database 
programming. My problem is I have two pages setup. One for paging through 
records in a database to make corrections to each field in a record. A 
Submit button links to a page with a "success" statement and the
required 
(PHP Update Object) and connector. Problem is when I change the value of any 
field in a record, the submit (Update Object) changes EVERY datafield of 
that name like (Fname) in the database to that value. If I use the Where is 
equal to clause to reference one (Key) field in a record it does fine for 
that record. The Key field is named Member_id and is incremented 
automatically. How can I set the Update Object to replace ONLY the corrected 
fields? Dumb questions make the world run. Help me out here.