Database integrity refers to the accuracy and consistency of data within a database. The four rules that help ensure database integrity are entity integrity, referential integrity, domain integrity, and user-defined integrity. Database realms are different scopes or contexts of data management, which can be categorized into data, object, and artifact realms.

1. Briefly explain the following as applied to database design.
What is Database integrity? Explain the four rules that help to ensure database integrity.
What is Database realms. Explain the three database realms.