i have a table with 3 fields: title start end
For some reason i want to have the following; the title has to be filled in always, but for the start and end field belongs a rule to the fields; only 1 of the two fields can be filledin, They also can't be either empty or filled in. It's up to the user which one of the 2 fields he wants to fill in, none of them is more important than the other.
