Time and Relational Theory

Front Cover
Time and Relational Theory
Copyright
Dedication
About the Authors
Contents
Preface
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
	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
	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
	Chapter 19: The SQL Standard
		Periods
		Database Design
		Queries
		Updates
		System Time
		Bitemporal Tables
		Summary and Assessment
		Exercises
		Answers
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