Temporal database systems are systems that provide special support for storing, querying, and updating historical and/or future data. Current DBMSs provide essentially no temporal features at all, but this situation is likely to change soon for a variety of reasons; in fact, temporal databases are virtually certain to become important sooner rather than later, in the commercial world as well as in academia. This book provides an in-depth description of the foundations and principles on which those temporal DBMSs will be built. These foundations and principles are firmly rooted in the relational model of data; thus, they represent an evolutionary step, not a revolutionary one, and they will stand the test of time.

This book is arranged in three parts and a set of appendixes:
Preliminaries: Provides a detailed review of the relational model, and an overview of the Tutorial D language.
Laying the Foundations: Explains basic temporal data problems and introduces fundamental constructs and operators for addressing those problems.
Building on the Foundations: Applies the material of the previous part to issues of temporal database design, temporal constraints, temporal query and update, and much more.
Appendixes: Include annotated references and bibliography, implementation considerations, and other topics.
Key features:
Describes a truly relational approach to the temporal data problem. Addresses implementation as well as model issues.
Covers recent research on new database design techniques, a new normal form, new relational operators, new update operators, a new approach to the problem of "granularity," support for "cyclic point types," and other matters.
Includes review questions and exercises in every chapter.
Suitable for both reference and tutorial purposes.

• Preface

  Part I Preliminaries: A Review of Relational Concepts

• An Overview of Tutorial D

  Part II Laying the Foundation: Time and the Database

• What Is the Problem? Intervals
• Opeartors on Intervals
• The EXPAND and COLLAPSE Operators
• The PACK and UNPACK Operators
• Generalizing the Relational Operators

  Part III Building on the Foundations: Database Design

• Integrity Constraints I: Candidate Keys and Related Constraints
• Integrity Constraints II: General Constraints
• Database Queries
• Database Updates
• Stated Times and Logged Times
• Point and Interval Types Revisited

  Appendixes:

• Implementation Considerations
• Generalizing the EXPAND and COLLAPSE Operators
• References and Bibliography
• Index