I have a list which collects the dates that systems were lasted tested on. Ideally therefore, I would like it to be a date field. This way, SP uses built-in functionality to validate the entries.
However, some of these systems have never been tested. It is hard to tell these systems, which have blank dates, to systems were no one has yet entered the information (which also have blank dates). Therefore, I'd like it if I could have some way for users to indicate "No Test Date", or some similar text.
Does anybody know how to achieve this? I considered using regex to check for either, but it's not allowed in column validation. I also considered using a default value of "Not updated", so any blanks would clearly mean the fields had never been tested, but had been updated. However, I get syntax errors when trying this.
Does anyone have any suggestions?