Thank you for clear explanations, but could you attach mocked up sample data as twbx.
You must avoid to attach real data, but we need dummy data to understand data structure.
Thanks for giving this a look, Shin. I'm doing something a bit different than that. I built a workbook based off of Superstore and attached it here for your reference. I want to see the values in both lists regardless of whether they are in the other list, but I only want a row highlighted when you click if it is in the other list. In the views, you'll see a calculated field Compare Customer Name which only lists the name if it's in both sets. The header is hidden, and then that's what's used for the highlight action. However, nulls are getting equated and highlighting other null values. I added text on the Compare dashboard for what I would like to see.
Thanks for any help you can offer!