Joe Celko has looked the code of SQL programmers and found a consistent and troubling pattern. This book shows the shift these programmers need to make to overcome this deadlock. By collecting and detailing the diverse standards of myriad industries, and then giving a declaration for the units that can be used in an SQL schema, Joe enables readers to write and implement portable data that can interface to any number external application systems. This book doesn't limit itself to one subject, but serves as a synopsis of measurement scales and data standards for all industries.