Time and Relational Theory

Time and Relational Theory

Temporal Databases in the Relational Model and SQL

2nd Edition - July 16, 2014

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  • Authors: C.J. Date, Hugh Darwen, Nikos Lorentzos
  • Paperback ISBN: 9780128006313
  • eBook ISBN: 9780128006757

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Time and Relational Theory provides an in-depth description of temporal database systems, which provide special facilities for storing, querying, and updating historical and future data. Traditionally, database management systems provide little or no special support for temporal data at all. This situation is changing because: Cheap storage enables retention of large volumes of historical data in data warehouses Users are now faced with temporal data problems, and need solutions Temporal features have recently been incorporated into the SQL standard, and vendors have begun to add temporal support to their DBMS products Based on the groundbreaking text Temporal Data & the Relational Model (Morgan Kaufmann, 2002) and new research led by the authors, Time and Relational Theory is the only book to offer a complete overview of the functionality of a temporal DBMS. Expert authors Nikos Lorentzos, Hugh Darwen, and Chris Date describe an approach to temporal database management that is firmly rooted in classical relational theory and will stand the test of time. This book covers the SQL:2011 temporal extensions in depth and identifies and discusses the temporal functionality still missing from SQL.

Key Features

  • Understand how the relational model provides an ideal basis for taming the complexities of temporal databases
  • Learn how to analyze and evaluate commercial temporal products with this timely and important information
  • Be able to use sound principles in designing and using temporal databases
  • Understand the temporal support recently added to SQL with coverage of the new SQL features in this unique, accurate, and authoritative reference
  • Appreciate the benefits of a truly relational approach to the problem with this clear, user friendly presentation


DBMS designers, implementers, and vendor personnel, Database designers, consultants and administrators, Information modelers, Database application designers and developers, Data warehouse personnel , database academics

Table of Contents

    • Dedication
    • About the Authors
    • Preface
      • Structure of the Book
      • Intended Readership
      • Acknowledgments
    • Part I: A Review of Relational Concepts
      • Part I A Review of Relational Concepts
      • Chapter 1. Types and Relations
        • The Running Example
        • Types
        • Relations
        • Exercises
        • Answers
      • Chapter 2. Relational Algebra
        • Rename
        • Restrict
        • Project
        • Union, Intersect, and Minus
        • Join
        • Matching and Not Matching
        • Extend
        • Image Relations
        • Group and Ungroup
        • Extend bis
        • Relational Comparisons
        • Formulating Expressions One Step at a Time
        • Relational Completeness
        • Exercises
        • Answers
      • Chapter 3. Relation Variables
        • Relations vs. Relvars
        • Relational Assignment
        • Keys
        • Foreign Keys
        • Database Constraints
        • Views
        • The Relational Model
        • Exercises
        • Answers
    • Part II: Laying the Foundations
      • Part II Laying the Foundations
      • Chapter 4. Time and the Database
        • Temporal Databases
        • Timestamped Propositions
        • Valid Time vs. Transaction Time
        • Some Fundamental Questions
        • Exercises
        • Answers
      • Chapter 5. What’s the Problem?
        • Revising the Running Example
        • Sample Constraints and Queries
        • Semitemporalizing the Example
        • Fully Temporalizing the Example
        • Exercises
        • Answers
      • Chapter 6. Intervals
        • What’s an Interval?
        • Applications of Intervals
        • Point and Interval Types
        • A More Searching Example
        • Exercises
        • Answers
      • Chapter 7. Interval Operators
        • Notation
        • Interval Comparisons
        • “Set Operators”
        • Queries
        • Concluding Remarks
        • Exercises
        • Answers
      • Chapter 8. The EXPAND and COLLAPSE Operators
        • Preliminary Remarks
        • Expanded Form
        • Collapsed Form
        • Operator Definitions
        • Unary Relations
        • Nullary Relations
        • Exercises
        • Answers
      • Chapter 9. The PACK and UNPACK Operators I: The Single-Attribute Case
        • Preliminary Examples
        • Packed Form
        • Unpacked Form
        • Further Queries
        • Exercises
        • Answers
      • Chapter 10. The PACK and UNPACK Operators II: The Multiattribute Case
        • PACKING and UNPACKING on NO Attributes
        • UNPACKING ON Two or More Attributes
        • PACKING ON Two or More Attributes
        • A Logical Difference
        • Equivalence of Relations
        • Expand and Collapse Revisited
        • Some Remarks on Redundancy
        • A More Complex Example
        • Exercises
        • Answers
      • Chapter 11. Generalizing the Algebraic Operators
        • A Motivating Example
        • Dyadic Operators
        • n-Adic Operators
        • Monadic Operators
        • Relational Comparisons
        • The Underlying Intuition
        • The Regular Operators Revisited
        • Exercises
        • Answers
    • Part III: Building on the Foundations
      • Part III Building on the Foundations
      • Chapter 12. Database Design I: Structure
        • The Running Example Revisited
        • Since Relvars Only
        • During Relvars Only
        • A New Normal Form
        • “The Moving Point Now
        • Both Since and During Relvars
        • Concluding Remarks
        • Exercises
        • Answers
      • Chapter 13. Database Design II : Keys and Related Constraints
        • Simplifying the Running Example
        • The Redundancy Problem
        • The Circumlocution Problem
        • PACKED ON
        • The Contradiction Problem
        • WHEN / THEN
        • Combining Specifications
        • PACKED ON without WHEN / THEN
        • WHEN / THEN without PACKED ON
        • Neither PACKED ON nor WHEN / THEN
        • Keys Revisited
        • Putting it all Tgether
        • Exercises
        • Answers
      • Chapter 14. Database Design III : General Constraints
        • The Nine Requirements
        • Since Relvars Only
        • During Relvars Only
        • Both Since and During Relvars
        • Syntactic Shorthands
        • Concluding Remarks
        • Exercises
        • Answers
      • Chapter 15. Queries
        • The Twelve Queries
        • Since Relvars Only
        • During Relvars Only
        • Both Since and During Relvars
        • Views Can Help
        • Exercises
        • Answers
      • Chapter 16. Updates
        • Since Relvars Only
        • During Relvars Only I: U_UPDATES
        • During Relvars Only II: Portion Specifications
        • During Relvars Only III: Multiple Assignment
        • Both Since and During Relvars
        • Views can Help
        • Exercises
        • Answers
      • Chapter 17. Logged Time and Stated Time
        • A Quick Review
        • A Closer Look
        • The Database and the Log
        • Terminology
        • Logged Times
        • Queries Involving Logged Time
        • Exercises
        • Answers
      • Chapter 18. Point and Interval Types Revisited
        • Ordered vs. Ordinal
        • Type Inheritance
        • Point Types Revisited
        • Numeric Point Types
        • Granularity Revisited
        • Interval Types Revisited
        • Concluding Remarks
        • Exercises
        • Answers
    • Part IV: SQL Support
      • Part IV SQL Support
      • Chapter 19. The SQL Standard
        • Periods
        • Database Design
        • Queries
        • Updates
        • System Time
        • Bitemporal Tables
        • Summary and Assessment
        • Exercises
        • Answers
    • Appendixes
      • Appendixes
      • Appendix A. Cyclic Point Types
        • The Weekday Example
        • Weekday as a Point Type
        • The Corresponding Interval Type
        • Allen’s Operators
        • Union, Intersect, and Minus
        • PACK and UNPACK
        • Exercises
        • Answers
      • Appendix B. Is Ordinality Necessary?
      • Appendix C. Generalizing PACK and UNPACK
        • Sets of Relations
        • Sets of Sets
        • Sets of Bags
        • Bags: A Digression
        • Other Kinds of Sets
        • Effect on “PACK and UNPACK ON”
      • Appendix D. A Tutorial D Grammar
      • Appendix E. Implementation Considerations
        • PACK and UNPACK
        • A Graphical Representation
        • Algebraic Operators
        • Update Operators
        • A Final Remark
      • Appendix F. References and Bibliography
    • Index

Product details

  • No. of pages: 560
  • Language: English
  • Copyright: © Morgan Kaufmann 2014
  • Published: July 16, 2014
  • Imprint: Morgan Kaufmann
  • Paperback ISBN: 9780128006313
  • eBook ISBN: 9780128006757

About the Authors

C.J. Date

C. J. Date has a unique stature in the database industry. Author or coauthor of well over 30 books on database management (including the bestselling An Introduction to Database Systems, currently in its 8th edition), he enjoys a reputation that’s second to none for his ability to explain complex technical issues in a clear and understandable fashion. He was inducted into the Computing Industry Hall of Fame in 2004.

Affiliations and Expertise

Independent author, lecturer, researcher, and consultant, specializing in relational database technology

Hugh Darwen

Hugh Darwen was employed in IBM’s software development divisions from 1967 to 2004. In the early part of his career, he was involved in DBMS development; from 1978 to 1982, he was one of the chief architects of an IBM product called Business System 12, a product that faithfully embraced the principles of the relational model. He was an active participant in the development of the international standard for SQL (and related standards) from 1988 to 2004. Based in the UK, he currently teaches relational database theory at Warwick University and is a tutor and course development consultant for the Open University. He has written two books on database management as well as coauthoring several with C.J. Date. He has received honorary degrees from the University of Wolverhampton and the Open University.

Affiliations and Expertise

Warwick University, UK

Nikos Lorentzos

Nikos A. Lorentzos is a Professor at the Agricultural University of Athens. He is mainly known for his research in temporal (and also in spatio-temporal) databases. He has participated in relevant European Union funded projects (prime researcher for the development of a Temporal DBMS). The temporal model he has proposed has been extensively evaluated by independent researchers with positive comments, it is decribed in books addressed to university students, it has been the basis of PhDs undertaken in Europe and it has attracted the interest of DBMS developers. He is co-editor of the book Spatiotemporal Databases: The Chorochronos Approach (spatio-temporal databases). He is active in Temporal, Spatial and Spatio-temporal Databases as well as in the development of DSSs and Expert Systems in the forestry and the agricultural domain.

Affiliations and Expertise

Professor at the Agricultural University of Athens, Greece

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  • MaximeRouthier Fri Jun 12 2020

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