How to force ArrayFormula to compare “line by line”

Question

I'd like to use ArrayFormula in Google Sheet to reduce computing time. I have to compare dates from column A to dates from column B and write result in column C. It's obvious when doing it line by line ("A2>B2"). It doesn't work when using arrayFormula because it compares the full Array in column A with array of column B. https://docs.google.com/spreadsheets/d/1ao6gWFiu7WnwQISjQbEdDhY7xJ-HjLvWZEVmjU6bKog/edit?usp=sharing

Thanks for any help you can provide !

Answer 1

That should work, but your formula would have to look like this

=ArrayFormula(A3:A9<B3:B9)

Or, if you'd want to use open ranges

=ArrayFormula(if(len(A3:A); A3:A<B3:B;))