CoreData - can't set empty string as default value for attribute

Question

I have an entity in my datamodel with a string attribute that is currently optional, and I\'d like to convert this to a required attribute with a default value of the empty stri

Answer 1

I resolved this by overriding the getter for my field - if it contains null, I return an empty string instead:

-(NSString *)unit {
    if ([self primitiveValueForKey:@"unit"] == NULL) {
        return @"";
    } else {
        return [self primitiveValueForKey:@"unit"];
    }
}

So far it seems to be doing the trick, and I would imagine it wouldn't impact migrations (although I don't know enough about them to say for sure). I don't really care whether there's a null or an empty string in the db, after all - so long as I get "" instead of null when I ask for the field.