Hi!
This is definitely possible, bearing in mind the small delay needed to update the data that’s linked. As linking to a form requires that form to have some data submitted, linking a form to itself is a 2-step process. First create the form without any logic referencing itself - below is a super lightweight example.
Demo Self-reference initial.xlsx (10.5 KB)
Then upload at least one submission (even if with dummy data that you delete later), and after it’s uploaded, change the settings to set data sharing as enabled, and then select the form itself from the drop-down in ‘import other project data’ (all in the ‘connect projects’ page).
Now you should be able to add the logic where the form references itself. Below is the updated lightweight example that checks whether 1 or more records already exist with the user-inputted user ID.
Demo Self-reference with logic.xlsx (10.7 KB)
Hope this helps!
