Database Reorganization—Principles and Practice

Database reorganization can be defined as changing some aspect of the way in which a database m arranged logically and/or physically. An example is changing from a one-toone to a one-to-many relationship. Reorganizatmn m a necessary function in a database system. This paper introduces the basic concepts of reorganization, including why it is performed. Many types of reorganization are described and classified into logical/physical levels. Then pragmatic issues such as reorganization strategies, a survey of several commercial reorganization facilities, case studies, and database administration cons~deratmns are covered. Finally, several research efforts are surveyed.