Get union of select_multiple responses

Congratulations on your first post @jedsilver! We're glad you're here. When you get a chance, please consider also introducing yourself on this forum thread. I'd also encourage you to add a picture as your avatar because it helps build community!

I thought about your question for a while and can't think of a way to make it happen. The function you're asking about isn't one of the available form operators and functions, and not part of searching and matching strings.

Can you provide any more details about the specific questions and option sets you're working with? Maybe someone has a clever suggestion for redesigning the questions to get the same information a different way?