Specifically, I have a form with several fields on it for a table. One of those fields has a unique alphanumeric code we type in that should only be used "once" in a record. Now the records already have the record id that is being used on all the parent-child table relationships.
We were going to just check the box called "Must be unique" for this alphanumeric field and call it a day, but the issue is that we also need to allow this field to be blank too. Not just for 1 record, but to allow many records to have this field be blank and pass.
We couldn't figure out a way to do that ... have a field contain only unique value if it is entered in, yet allow blank values if they are not. The only way we seemed to be going towards is a lookup against that field, but it makes the whole form sluggish and useless.
We're trying to do this in a form because we want it so when a user decides to type in a value into this field, the form will block the save if that value already exists in another record as being used. If the user decides not to attach a value to this field and leaves it blank, then it will save.
