I created an InfopathForm to enter data in SP List B. Both SharePoint List A and B contain the same unique column, MEMBER ID. The user will enter the MEMBER ID and query both lists A and B. Basically, List A contains the data set they need to review and take action on. List B will contain the action they took on that item via a drop down and a small text box. The users may work an item multiple times as List A will be refreshed monthly. List A is already over 5000 and List B will also be above 5000. I have entered MEMBER ID =“0001” and pull back data from List A and changed a drop down to “Active” and added a note via the NEWIF form and saved it. When I open the NEWIF form again and QUERRY it pulls back the same setup data from LIST A and the “ACTIVE” & note previously added. When I change to the drop down to “Terminated” and click save, I get the Member ID cannot contain duplicate ID. However, if I go into LIST B and open in edit mode, make the change, and save, it updates, which it should. However, I nor my client wants their users having to switch between the NEWIF form to search the list to make updates. How would I create a rule that would switch the InfoPath form displayed to the user from the NEWIF to the EDITIF form based if my List B query string is NOT NULL?