Contents Contents 1 Introduction Entity Types... 37

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1 1 Introduction Functions of an Information System The Memory Function The Informative Function The Active Function Examples of Information Systems Conceptual Modeling The Structural Schema The Information Base The Behavioral Schema Integrity Constraints Derivation Rules The Principle of Necessity for Conceptual Schemas The Abstract Architecture of an Information System Requirements Engineering Quality of Conceptual Schemas A Brief History of Conceptual Modeling Logical Models Semantic Data Models Conceptual Models of Information Systems Object Orientation Bibliographical Notes Entity Types Introduction Definitional Concepts Functions of a Concept Prototypical Concepts... 39

2 xix Exemplar-Based Concepts Design of Concepts Definition of Entity Types Names Population Subsumption Representation in an Information System State of the Information Base Logical Representation Representation in UML Conceptual Models: Single or Multiple Classification Conceptual Models: Static or Dynamic Classification Properties of the Representation Data Types Data Types in UML Bibliographical Notes Exercises Relationship Types Definition Degree Pattern Sentence Unary Relationship Types Population Subsumption Representation in an Information System State of the Information Base Logical Representation Representation in UML Properties of the Representation Attributes Conceptual Models Based on Attributes Attribute Pattern Sentence Representation in UML On the Use of Attributes Bibliographical Notes Exercises Cardinality Constraints Cardinality Constraints of Binary Relationship Types Existence Dependency Relationship Types Attributes...86

3 xx Recursive Relationship Types Satisfiability of Cardinality Constraints Cardinality Constraints of n-ary Relationship Types Consistency and Inference Rules Maximal Participation Bibliographical Notes Exercises Particular Kinds of Relationship Type Reference Relationship Types Simple Reference Compound Reference Set Reference Identification Identifiability of Entity Types Replacing Entities with Identifiers in Relationships Elementary Relationship Types Decomposing NonElementary Relationship Types Decomposition Based on Functional Dependencies Decomposition Based on Multivalued Dependencies Decomposition by Absorbing a Constant Entity Type Bibliographical Notes Exercises Reification Definition Representation in UML Association Classes Implicit Reification Implicit Reification as a Schema Transformation Partial Reification Bibliographical Notes Exercises Generic Relationship Types Definition Representation in an Information System Logical Representation Representation in UML Part Whole Relationships Description Representation in UML

4 xxi Part Sharing Part Dependency Grouping Description Representation in UML Homogeneous Versus Heterogeneous Groups Roles Description Representation in UML Propagation Materialization Description Representation in UML Inheritance Bibliographical Notes Exercises Derived Types Derivability Base Types Derived Types Hybrid Types Transformation of Hybrid Types into Derived Types Design of Derivability Representation in an Information System Logical Representation Representation in UML Representation of Derivation Rules by Operations Particular Kinds of Derived Type Derived by Union Derived by Specialization Derived by Exclusion Derived by Participation Transitive Closure Derivation Rules for Constant Relationship Types Hybrid Types in UML Justification for Derived Types Bibliographical Notes Exercises Integrity Constraints The Concept of an Integrity Constraint...181

5 xxii Integrity = Validity + Completeness Integrity Constraints Violation of Integrity Constraints Violation Response Actions Classification of Integrity Constraints Classification According to Source Classification According to Scope Classification According to Cause of Violation Representation in an Information System Logical Representation Representation in UML Representation of Constraints by Operations Particular Kinds of Static Constraint Key Constraints Reference Constraints Inclusion Constraints Disjunction Constraints Covering Constraints Constraints of Recursive Binary Relationship Types Entity Type Cardinality Constraints Creation-Time Constraints Bibliographical Notes Exercises Taxonomies Specialization The IsA Relationship Entity Types Derived by Intersection and Multiple Classification The Entity Type Entity Generalization The Gens Relationship Constraints on Generalizations Generalization/Specialization Dimension Explicit Subtypes versus Explicit Dimension Attributes Partitions The Taxonomy of a Conceptual Schema Valid Type Configurations Taxonomic Constraints and Derivability Partitions and Derivability Relationship Type Refinement Participant Refinement

6 xxiii Particular Kinds of Participant Refinement Cardinality Constraint Strengthening Interaction of IsA and Cardinality Constraints Derivation Rule Redefinition Redefining a Base Relationship Type as Derived Constraint Specialization Specialization/Generalization of Relationship Types IsA and Gens Between Relationship Types Reification and Specialization Bibliographical Notes Exercises Domain Events Domain Events as Sets of Structural Events Structural Events Domain Events Representation in an Information System Domain Events as Entities Logical Representation UML Representation Domain Event Constraints Logical Representation UML Representation Event Effects: The Postcondition Approach Logical Representation UML Representation The Frame Problem Event Effects: The Procedural Approach Logical Representation UML Representation Consistency with the Structural Schema Bibliographical Notes Exercises Action Request Events Actions and Action Request Events Scope of this Chapter Action Request Event Types Characteristics of Action Request Events Constraints of Action Request Events Effects of Queries Effects of Action Request Events...289

7 xxiv Effects of Domain Event Notifications Event Specialization Generating Conditions Bibliographical Notes Exercises State Transition Diagrams Finite State Machines Finite Automata Moore and Mealy Machines Entities as State Machines Entity Life Cycle State Transition Diagrams in UML Transitions Triggered by Change and Time Events Unexpected-Event Reception Initial State Final State Junction Choice From Domain and Action Request Events to Call Events Localization of Event Constraints and Effects Entity Types with Multiple State Transition Diagrams Bibliographical Notes Exercises Statecharts The State Hierarchy Simple Composite States State Configuration and Entity Life Cycle Initial Pseudostate Conflicting Transitions Parallelism Initial Pseudostate Firing Multiple Transitions Fork Join Bibliographical Notes Exercises Use Cases Actors Use Cases

8 xxv Definition Use Case Actors Use Case Specification Relationships Between Use Cases Use Case Model Mapping Use Cases to Requests Textual References Creation Dependencies Sequence Diagrams Bibliographical Notes Exercises Case Study Main Domain Concepts Store Configuration Store Data Minimum Values Store Administration Manufacturers Categories Products Customers Online Catalog Shopping Carts Orders Show Previous Orders Metamodeling Meta Entity Types Definition Classification Level InstanceOf versus IsA Monolevel and Multilevel Information Bases Logical Representation Representation in UML Powertypes Class Relationship Types Meta Relationship Types Definition Logical Representation Representation in UML Metaschemas...400

9 xxvi Definition Example of a Metaschema Levels of a Meta Information Base The Importance of Metaschemas Conceptual Models versus Metaschemas The UML Metaschema Stereotypes Definition Stereotypes in the Metaschema Bibliographical Notes Exercises The MOF and XMI Meta-Metaschemas Definition The MOF The MOF as a Conceptual Modeling Language The MOF as an ω-metaschema XMI XMI Representation of Entities and Relationships XMI Representation of UML Schemas Bibliographical Notes Exercises References Index Index