Hello
I'm looking for a way to prevent double entries in a Sharepoint list.
I have 3 lists: One list with names and addresses of Students. (called students), one with names of courses they can subscribe for (called courses) and another called subscriptions, used when a student subscribes for a course. A student can subscribe for multiple courses.
I want to prevent that when subscribing a student for a course, the student allready has a subscription for this course. Sometimes it happens that a student does a subscription and has to wait for the course to start (sometimes more than one year). In that case they sometimes come back a few months after the first subscription and want to subscribe again for the same course. To prevent double entries, I want sharepoint to do a checkup before subscribing the same student for the same course again. If the check is positive, I want the user to be prompted that the student allready has a subscription for this course. When the check is negative, I want the data entered in the subscription form to be saved in the sharepoint list.
Because the subscription list uses lookup fields from both the courses and students list, sharepoint doesn't let me combine values from those fields in a calculated column to make sure these values are unique entries.
I read that to solve this problem, I need to use Power automate to do the check-up.
Is that correct, and is it the simplest solution? How do I get started?
Thanks!
