Struggling to use formula function within fileClass

I am struggling to get the Formula function to achieve even the most basic recall of information using fileClasses in my note YAML. Where can I find more information on this?

Are you talking about formulas for DB folder or Meta data plugins? It doesn’t seem like you’re talking about a dataview query.

Could you show some examples of what you’ve tried, even if they’re failing? And decribe a use case you’d like to solve?