Thanks everybody for the inputs!! Ann, You are right: space is no longer an issue these days... It's just that I always keep asking whether is "the best" or the "correct" way to do it...
I'm not an expert in the matter, but I guess that having a field which in most of cases will be null, is against normalization rules. Isn't it? Anyway, I will put it on the main invoices table, and stop messing with this kind of questions!! Thanks again!! :)
