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Time and Relational Theory, 2nd Edition

Book Description

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.

  • 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

Table of Contents

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