How can I make a user’s rating on a photo unique?
Sheet1 is formed in this motion:
Photo ID, photo, voting, email, I created a realtion column that relates photo Id to voting column, then I created a column Lookup retrieves the emails from the email column.
I configured a button that when pressed retrieves the user email from the User table and writes it in the email column of sheet 1, and makes the button to limit the votes disappear.
It works, but the problem is that only one user will be able to vote since the email column has already been populated by the previous user who voted.
How do I make the vote unique for each individual user?
Do I need to retrieve user id from user table?
I don’t understand what logic I should use.
Thank you for your attention