文档介绍：CONTENTS
PREFACE xxii
Part I BASICS 1
1 INTRODUCTION TO DATABASE SYSTEMS 3
Overview 4
A Historical Perspective 5
File Systems versus a DBMS 7
Advantages of a DBMS 8
Describing and Storing Data in a DBMS 9
The Relational Model 10
Levels of Abstraction in a DBMS 11
Data Independence 14
Queries in a DBMS 15
Transaction Management 15
Concurrent Execution of Transactions 16
plete Transactions and System Crashes 17
Points to Note 18
Structure of a DBMS 18
People Who Deal with Databases 20
Points to Review 21
2 THE ENTITY-RELATIONSHIP MODEL 24
Overview of Database Design 24
Beyond the ER Model 25
Entities, Attributes, and Entity Sets 26
Relationships and Relationship Sets 27
Additional Features of the ER Model 30
Key Constraints 30
Participation Constraints 32
Weak Entities 33
Class Hierarchies 35
Aggregation 37
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viii Database Management Systems
Conceptual Database Design With the ER Model 38
Entity versus Attribute 39
Entity versus Relationship 40
Binary versus Ternary Relationships * 41
Aggregation versus Ternary Relationships * 43
Conceptual Design for Large Enterprises * 44
Points to Review 45
3 THE RELATIONAL MODEL 51
Introduction to the Relational Model 52
Creating and Modifying Relations Using SQL-92 55
Integrity Constraints over Relations 56
Key Constraints 57
Foreign Key Constraints 59
General Constraints 61
Enforcing Integrity Constraints 62
Querying Relational Data 64
Logical Database Design: ER to Relational 66
Entity Sets to Tables 67
Relationship Sets (without Constraints) to Tables 67
Translating Relationship Sets with Key Constraints 69
Translating Relationship Sets with Participation Constraints 71
Translating Weak Ent