In the workflow rule I create a PDF and the Attachment Name via a formula that concatenates some columns. In some of them are characters that we cannot use for filenames. I now use SUBSTITUTE like:
<<SUBSTITUTE(SUBSTITUTE(CONCATENATE([Column1] , [Column2])
, “/” , “") , ‘"’ , "”)>>
to substitute / and ".
Could AppSheet do that automatically for us? While creating a PDF it should substitute all the forbidden characters: ? * < > . , \ + : = / " ; [ ] |