Can the current() function be used in data validation expressions? For example if I want to make sure that the total of all entries in field 2 with a field 1 value of the current instance of field 1 doesn't total to more than 8, could the current() function be used to get the value of the current instance of field 1 and use that value to filter when I use the sum() function? If my example isn't clear enough, let me know and I will post a more specific example that might make it clearer.