Formula into a single select

[SophieULB]

Hi,

To explain a bit : 

We have workshops that happen on different dates and people can register to those in a form.

So I created a formula with the name of the workshop + the date of the workshop. I want that, in the form, people can only chose on date at the time. Now they can register for multiple dates and it creates complicate data for confirmation emails and reminders.

So I was thinking that if the formula (Name + date) was a single select, they could only register at one but if there is another way, I take any advices 🙂

Can anyone help me? 

[Sho]

It would be a better way to create a new "Name+Date" workshop table and link it to the other tables in the link field.
This way, you can filter out any workshops that have been completed so that they do not show up.