I am following the info here:
I am using the formula as specified by casting a date time to a string, then taking a substring of that and using as a parameter to cast to a date. I am doing this in the formula builder to populate a field of datatype date, marked as a calculated value.
Since this wasn't working, I created a new filed, of the text field data type, and tried entering a formula that is simply toString($date_entered) where $date_entered is the datetime field I am trying to work with. This also fails, and neither the new date field nor the new text field are populated. What am I doing wrong? And can someone point me toward the documentation for all data types and functions?