Here's a senario. A user is entering data in a form that has quite a few objects. The user gets to the last object(textbox maybe) and finishes to hit SAVE on the form, or equiv procedure. VFP notices one of the table's primary keys have been violated. In this case there might be 10 tables attached to the form, where one of the tables is simply a state table with it's primary key on state abbreviation. Does VFP let the user change the state abbreviation after it noticed the user entered in a dup? Nope. It wipes the whole form out and makes the user start all over. If you revert you throw away all changes, and you have to revert. What does a programmer do to prevent this besides not letting users have access to the primary key of any table?