A field attains field-level integrity after you've defined a complete set of field specifications for the field. Field-level integrity warrants the following:
The identity and purpose of a field is clear, and all of the tables in which it appears are properly identified.
Field definitions are consistent throughout the database.
The values of a field are consistent and valid.
The types of modifications, comparisons, and operations that can be applied to the values in the field are clearly identified.
You can guarantee that a field structure is sound and optimally designed when it has a complete set of field specifications and fully conforms to the Elements of the Ideal Field. In fact, ensuring that the field complies ...