构建可扩展数据库应用程序PDF电子书下载

3.5 Example:Student Administration 3 1

Part One An Object-Oriented View on Persistence 1

Chapter 1 A New Generation of Software 3

1.1 FromDatatoInformation 3

1.2 Improving Software Quality 4

1.3 Databases Everywhere 4

1.4 ToHave andtoHold 5

1.5 Concentrating on the Essence 5

1.6 The Importance of Scalability 6

1.7 Application Program Interfaces 7

1.8 TheRoadtoFollow 7

2.1 Walking among Dinosaurs 9

Chapter 2 The Database Community Today 9

2.3 Database Users 10

2.2 Database Usage 10

2.4 Designing Database Applications 11

Contents 11

Foreword 11

2.5 Relational Databases 12

Preface 13

2.6 Client/Server Systems 15

Acknowledgments 17

2.7 Distributed Software 18

2.8 Problems with Traditional Systems 19

About theAuthor 19

2.9 4GL:The Solution? 20

2.10 Object-Oriented Databases 21

2.11 Preserving Openness 23

2.12 Summary 24

3.1 Data-Driven Software Design 25

Chapter 3 An Object-Oriented View on Database Applications 25

3.2 Supporting Multiple Applications 28

3.3 Object-Oriented Software Design 29

3.4 The Object Model 30

3.6 Business Models and Supporting Multiple Applications 34

3.7 C++,Java,or Smalltalk:The Ultimate Answer? 35

3.8 Building Reusable Software 38

3.11 User Interfaces 40

3.10 Object Orientation and Client/Server Design 40

3.9 Toward Open Client/Server Applications 40

3.12 Analogy between User Interfaces and Databases 41

3.13 Object-Oriented or Relational? 43

3.14 Persistence from a Different Angle 44

3.15 Persistence and Separation of Concerns 44

3.16 Safety Issues 46

3.17 Summary 46

Part Two An Architecture for Object Persistence 47

4.1 Introduction 49

Chapter 4 Making Objects Persistent 49

4.2 Basic Requirements of a Persistence Framework 50

4.3 Obtaining Scalability 50

4.4 Interfacing with a Relational World:Problems to Conquer 51

4.5 Abstracting the Database 57

4.6 An Architecture for Object Persistence 58

4.7 Summary 60

5.1 A Persistent Container Class 61

5.2 Basic Functionality of PSet 61

Chapter 5 Abstracting the Database 61

5.3 Implementing the Persistence Architecture 63

5.4 Resolving the Impedance Mismatch 65

5.5 Reading and Writing Objects 71

5.6 Direct Instances of PSet 73

5.7 Searching for Objects 75

5.8 Supporting Multiple Technologies 79

5.9 Summary 81

6.1 Deriving from PSet 83

Chapter 6 Encapsulating Data Access 83

6.2 Example:Class City 87

6.3 Using Class City 93

6.4 Member Objects 93

6.5 Derived IM Resolvers 94

6.6 Class Extension 99

6.7 Compile-Time Decoupling 100

6.8 Reuse and Migration to Other Technologies 104

6.9 Summary 104

Part Three Implementing Business Models 105

7.1 Developing a Simple Invoicing System 107

Chapter 7 Designing Business Objects 107

7.2 Searching Compound Objects 116

7.3 Object ID versus Primary Key 118

7.4 Developing Generic IM Resolvers 121

7.5 An OID-Based Reference Class 126

7.6 Supporting Existing Database Layouts 130

7.7 Versioning 131

7.8 Stability of Program Code against Schema Changes 134

7.9 Storing Multimedia Objects 135

7.10 Efficiency 139

7.11 Summary 145

Chapter 8 Inheritance of Persistent Objects 147

8.1 Specialization:Using Inheritance for Reuse 147

8.2 Generalization:Using Inheritance for Polymorphism 152

8.3 Using Generalizations as Member Objects 158

8.4 Inheritance in Relational Database Systems 162

8.5 Designing Reusable Software Components 170

8.6 Summary 173

9.1 Many-to-One Relationships 175

Chapter 9 Associations 175

9.2 Attributes versus Associations 176

9.3 Collections:One-to-Many Relationships 178

9.4 Associations and Reuse 186

9.5 Many-to-Many Relationships 188

9.6 A Closer Look at Associations 189

9.7 Associations as Independent Entities 191

9.8 Referential Integrity 197

9.9 Summary 202

10.2 The ACID Test 203

Chapter 10 Transaction Management and Concurrency Control 203

10.1 The Transaction 203

10.3 Transaction Management Exceeds the Database Level 205

10.4 Concurrency Control:Locking 206

10.5 Example:A Transaction Class 211

10.6 Transactions in Relational Database Systems 212

10.7 Using Transactions 214

10.8 Nested Transactions 215

10.9 Distributed DatabaseSystems 217

10.10 Other Levels ofConcurrency 219

10.11 Lock Notification through Call-Back Functions 221

10.12 Summary 222

Chapter 11 The Front End 223

11.1 Analogy between User Interfaces and Databases 223

11.2 Separating the User Interface from the Business Model 223

11.3 WhattoPutWhere 229

11.4 Navigating through Persistent Sets 229

11.5 Summary 234

12.1 ProjectDefinition 235

Chapter 12 Case Study:An Electronic Telephone Directory 235

12.2 Comparing Development Approaches 236

12.3 Designing the User Interface 237

12.4 The Database Model 240

12.5 Designing the Business Model 240

12.6 Comparing the Business Model and the Database Model 243

12.7 Implementing the Business Objects 244

12.8 Making Classes Persistent 250

12.9 Impedance Mismatch Examples 257

12.10 Implementing the User Interface 263

12.11 Summary 275

Chapter 13 Toward Open Applications 277

13.1 Third-Party Access to Your Application's Data 278

13.2 Standard Report Generators and Query Tools 278

13.3 Informationbases 281

13.4 Interoperability with Other Applications 282

13.5 Implementing an Informationbase 285

13.6 Architecture for Next-Generation Software 286

13.7 Summary 289

Chapter 14 Conclusion 291

Appendix DBtools-Based Implementation of Scoop 293

PSet 293

DataSet 294

IM Resolver 294

Resolving Impedance Mismatch 295

Building the Select Statement 296

References 297

Index 301