Bitemporal Databases

All mainstream database systems lack support for
temporal metadata, and instead store only the most
recent data. Consequently, they can only manage
temporal data in an ad hoc manner -- oftentimes not
effectively. Yet there are countless application
domains that need temporal data. This book offers a
much-needed solution: It includes a bitemporal
relational data model, based on nested relations, as
well as its algebra and calculus languages for
expressing queries. The fundamental construct for
representing temporal data is a bitemporal atom; a
value, its validity period, and the time this data
was recorded in the database. The concept of context defines different views of bitemporal data.
BtSQL, a simple bitemporal variation of the SQL, is
introduced. The book also provides a prototype
implementation, which demonstrates the feasibility of
the proposed approach in an object-relational
database system. Researchers and practitioners in
database development will find this book useful. It
can be used as a textbook in advanced database
courses -- particularly in application domains where
temporal metadata can greatly leverage the value of
the data as it is stored and utilized.