DATABASE SYSTEMS (phần 1) ppt

Our presentations stresses the fundamentals of database modeling and design, the languages and facilities provided by the database management systems, and system implementation technique

., FUNDAMENTALS OF

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To Amalia with love

R E.

To my motherVijaya and wife Aruna for their love and support

S B.N.

This book introduces the fundamental concepts necessary for designing, using, and

imple-menting database systems and applications Our presentations stresses the fundamentals

of database modeling and design, the languages and facilities provided by the database

management systems, and system implementation techniques The book is meant tobe

used as a textbook for a one- or two-semester course in database systems at the junior,

senior or graduate level, and as a reference book We assume that the readers are familiar

with elementary programming and data-structuring concepts and that they have had

some exposureto the basic computer organization

We start in Part I with an introduction and a presentation of the basic concepts and

terminology, and database conceptual modeling principles We conclude the book in

Parts 7 and 8 with an introduction to emerging technologies, such as data mining, XML,

security, and Web databases Along the way-in Parts 2 through 6-we provide an

in-depth treatment of the most important aspects of database fundamentals

The following key features are included in the fourth edition:

• The entire book follows a self-contained, flexible organization that can be tailored to

individual needs

• Coverage of data modeling now includes both theERmodel andUML

• A new advancedSQLchapter with material onSQLprogramming techniques, such as

]DBCandSQL/CLl.

• A new chapter onXMLand Internet databases.

• A new chapter on data mining

• A significant revision of the supplements to include a robust set of materials forinstructors and students, and an online case study

Main Differences from the Third Edition

There are several organizational changes in the fourth edition, as well as some importantnew chapters The main changes are as follows:

• The chapters on file organizations and indexing (Chapters 5 and 6 in the third tion) have been moved to Part 4, and are now Chapters 13 and 14 Part 4 alsoincludes Chapters 15 and 16 on query processing and optimization, and physicaldatabase design and tuning (this corresponds to Chapter 18 and sections 16.3-16.4 ofthe third edition)

edi-• The relational model coverage has been reorganized and updated in Part 2 Chapter

5 covers relational model concepts and constraints The material on relational bra and calculus is now together in Chapter 6 Relational database design using ER-to-relational and EER-to-relational mapping is in Chapter 7 SQL is covered inChapters 8 and 9, with the new material in SQL programming techniques in sections9.3 through 9.6

alge-• Part 3 covers database design theory and methodology Chapters 10 and lion ization theory correspond to Chapters 14 and 15 of the third edition Chapter 12 onpractical database design has been updated to include more UML coverage

normal-• The chapters on transactions, concurrency control, and recovery (19, 20, 21 in thethird edition) are now Chapters 17, 18, and 19 in Part 5

• The chapters on object-oriented concepts, ODMG object model, and object-relationalsystems (11,12,13 in the third edition) are now 20, 21, and 22 in Part 6 Chapter 22has been reorganized and updated

• Chapters 10 and 17 of the third edition have been dropped The material on server architectures has been merged into Chapters 2 and 25

client-• The chapters on security, enhanced models (active, temporal, spatial, multimedia), anddistributed databases (Chapters 22, 23, 24 in the third edition) are now 23, 24, and 25

in Part 7 The security chapter has been updated Chapter 25 of the third edition ondeductive databases has been merged into Chapter 24, and is now section 24.4

• Chapter 26 is a new chapter on XML (eXtended Markup Language), and how it is

related to accessing relational databases over the Internet

• The material on data mining and data warehousing (Chapter 26 of the third edition)

has been separated into two chapters Chaprer 27 on data mining has been expanded

and updated

Contents of This Edition

Part 1 describes the basic concepts necessary for a good understanding of database design

and implementation, as well as the conceptual modeling techniques used in database

sys-tems Chapters 1 and 2 introduce databases, their typical users, and DBMS concepts,

ter-minology, and architecture In Chapter 3, the concepts of the Entity-Relationship (ER)

model and ER diagrams are presented and used to illustrate conceptual database design

Chapter 4 focuses on data abstraction and semantic data modeling concepts and extends

the ER model to incorporate these ideas, leading to the enhanced-ER (EER) data model

and EER diagrams The concepts presented include subclasses, specialization,

generaliza-tion, and union types (categories) The notation for the class diagrams of UML are also

introduced in Chapters 3 and 4

Part 2 describes the relational data model and relational DBMSs Chapter 5 describes

the basic relational model, its integrity constraints and update operations Chapter 6

describes the operations of the relational algebra and introduces the relational calculus

Chapter 7 discusses relational database design using ER and EER-to-relational mapping

Chapter 8 gives a detailed overview of the SQL language, covering the SQL standard,

which is implemented in most relational systems Chapter 9 covers SQL programming

topics such as SQL], JDBC, and SQL/CLI

Part 3 covers several topics related to database design Chapters 10 and 11 cover the

formalisms, theories, and algorithms developed for the relational database design by

nor-malization This material includes functional and other types of dependencies and normal

forms of relarions Step-by-step intuitive normalizarion is presented in Chapter 10, and

relational design algorithms are given in Chapter 11, which also defines other types of

dependencies, such as multivalued and join dependencies Chapter 12 presents an

over-view of the different phases of the database design process for medium-sized and large

applications, using UML

I Part 4 starts with a description of the physical file structures and access methods used

in database systems Chapter 13 describes primary methods of organizing files of records

on disk, including static and dynamic hashing Chapter 14 describes indexing techniques

for files, including B-tree and B+-tree data structures and grid files Chapter 15 introduces

the basics of query processing and optimization, and Chapter 16 discusses physical

data-base design and tuning

Part 5 discusses transaction processing, concurrency control, and recovery

tech-niques, including discussions of how these concepts are realized in SQL

Preface IIX

x I Preface

Part 6 gives a comprehensive introduction to object databases and object-relationalsystems Chapter 20 introduces object-oriented concepts Chapter 21 gives a detailedoverview of theODMGobject model and its associatedODL and OQL languages Chapter

22 describes how relational databases are being extended to include object-oriented cepts and presents the features of object-relational systems, as well as giving an overview

con-of some con-of the features con-of theSQL3standard, and the nested relational data model.Parts 7 and 8 cover a number of advanced topics Chapter 23 gives an overview ofdatabase security and authorization, including the SQL commands to GRANT andREVOKE privileges, and expanded coverage on security concepts such as encryption,roles, and flow control Chapter 24 introduces several enhanced database models foradvanced applications These include active databases and triggers, temporal, spatial, mul-timedia, and deductive databases Chapter 25 gives an introduction to distributed data-bases and the three-tier client-server architecture Chapter 26 is a new chapter on XML(eXtended Markup Language) Itfirst discusses the differences between structured, semi-structured, and unstructured models, then presents XML concepts, and finally comparesthe XML model to traditional database models Chapter 27 on data mining has beenexpanded and updated Chapter 28 introduces data warehousing concepts Finally, Chap-ter 29 gives introductions to the topics of mobile databases, multimedia databases, GIS(Geographic Information Systems), and Genome data management in bioinformatics.Appendix A gives a number of alternative diagrammatic notations for displaying a con-ceptualERorEERschema These may be substituted for the notation we use, if the instructor

so wishes Appendix C gives some important physical parameters of disks Appendixes B, E,and F are on the web site Appendix B is a new case study that follows the design and imple-mentation of a bookstore's database Appendixes E and F cover legacy database systems,based on the network and hierarchical database models These have been used for overthirty years as a basis for many existing commercial database applications and transaction-processing systems and will take decades to replace completely We consider it important toexpose students of database management to these long-standing approaches Full chaptersfrom the third edition can be found on the web site for this edition

Guidelines for Using This Book

There are many different ways to teach a database course The chapters in Parts 1 through

5 can be used in an introductory course on database systems in the order that they aregiven or in the preferred order of each individual instructor Selected chapters and sec-tions may be left out, and the instructor can add other chapters from the rest of the book,depending on the emphasis if the course At the end of each chapter's opening section,

we list sections that are candidates for being left out whenever a less detailed discussion ofthe topic in a particular chapter is desired We suggest covering up to Chapter 14 in anintroductory database course and including selected parts of other chapters, depending onthe background of the students and the desired coverage For an emphasis on systemimplementation techniques, chapters from Parts 4 and 5 can be included

Chapters 3 and 4, which cover conceptual modeling using theERandEERmodels, areimportant for a good conceptual understanding of databases However, they may be par-

tially covered, covered later in a course, or even left out if the emphasis is onDBMS

imple-mentation Chapters 13 and 14 on file organizations and indexing may also be covered

early on, later, or even left out if the emphasis is on database models and languages For

students who have already taken a course on file organization, parts of these chapters

could be assigned as reading material or some exercises may be assigned to review the

concepts

A total life-cycle database design and implementation project covers conceptual

design (Chapters 3 and 4), data model mapping (Chapter 7), normalization (Chapter

10), and implementation inSQL (Chapter 9) Additional documentation on the specific

RDBMSwould be required

The book has been written so that it is possible to cover topics in a variety of orders

The chart included here shows the major dependencies between chapters As the diagram

illustrates, it is possible to start with several different topics following the first two

intro-ductory chapters Although the chart may seem complex, it is important to note that if

the chapters are covered in order, the dependencies are not lost The chart can be

con-sulted by instructors wishing to use an alternative order of presentation

For a single-semester course based on this book, some chapters can be assigned as

read-ing material Parts 4,7, and 8 can be considered for such an assignment The book can also

Preface IXI

xii Preface

\

be used for a two-semester sequence The first course, "Introduction to Database Design/Systems," at the sophomore, junior, or senior level, could cover most of Chapters 1to 14.The second course, "Database Design and Implementation Techniques," at the senior orfirst-year graduate level, can cover Chapters 15 to 28 Chapters from Parts 7 and 8 can beused selectively in either semester, and material describing the DBMS available to the stu-dents at the local institution can be covered in addition to the material in the book

Supplemental Materials

The supplements to this book have been significantly revised With Addison-Wesley'sDatabase Place there is a robust set of interactive reference materials to help studentswith their study of modeling, normalization, and SQL Each tutorial asks students to solveproblems (such as writing an SQL query, drawing an ER diagram or normalizing a rela-tion), and then provides useful feedback based on the student's solution Addison-Wesley's Database Place helps students master the key concepts of all database courses.For more information visitaw.corn/databaseplace

In addition the following supplements are available to all readers of this book atwww.aw.com/cssupport

• Additional content: This includes a new Case Study on the design and tion of a bookstore's database as well as chapters from previous editions that are notincluded in the fourth edition

implementa-• A set of PowerPoint lecture notes

A solutions manual is also available to qualified instructors Please contact your localAddison- Wesley sales representative, or send e-mail to aw.cseteaw.com, for information

on howtoaccess it

Acknowledgements

It is a great pleasure for us to acknowledge the assistance and contributions of a large ber of individuals to this effort First, we would like to thank our editors, Maite Suarez-Rivas, Katherine Harutunian, Daniel Rausch, and Juliet Silveri In particular we would like

num-to acknowledge the efforts and help of Katherine Harutunian, our primary contact for thefourth edition We would like to acknowledge also those persons who have contributed tothe fourth edition We appreciated the contributions of the following reviewers: Phil Bern-hard,Florida Tech; Zhengxin Chen,University of Nebraska at Omaha;Jan Chomicki,Univer-

Ramez Elmasri would like to thank his students Hyoil Han, Babak Hojabri, Jack Fu,CharleyLi, Ande Swathi, and Steven Wu, who contributed to the material in Chapter

26 He would also like to acknowledge the support provided by the University of Texas at

Arlington

Sham Navathe would like to acknowledge Dan Forsythe and the following students

at Georgia Tech: Weimin Feng, Angshuman Guin, Abrar Ul-Haque, Bin Liu, Ying Liu,

Wanxia Xie and Waigen Yee

We would like to repeat our thanks to those who have reviewed and contributed to

ptevious editions ofFundamentals of Database Systems For the first edition these

individu-als include Alan Apt (editor), Don Batory, Scott Downing, Dennis Heimbinger, Julia

Hodges, Yannis Ioannidis, Jim Larson, Dennis McLeod, Per-Ake Larson, Rahul Patel,

Nicholas Roussopoulos, David Stemple, Michael Stonebraker, Frank Tampa, and

Kyu-Young Whang; for the second edition they include Dan [oraanstad (editor), Rafi Ahmed,

Antonio Albano, David Beech, Jose Blakeley, Panos Chrysanthis, Suzanne Dietrich, Vic

Ghorpadey, Goets Graefe, Eric Hanson, [ungukL.Kim, Roger King, Vram Kouramajian,

Vijay Kumar, John Lowther, Sanjay Manchanda, Toshimi Minoura, Inderpal Mumick, Ed

Omiecinski, Girish Pathak, Raghu Rarnakrishnan, Ed Robertson, Eugene Sheng, David

Stotts, Marianne Winslett, and Stan Zdonick For the third edition they include Suzanne

Dietrich, Ed Omiecinski, Rafi Ahmed, Francois Bancilhon, Jose Blakeley, Rick Cattell,

Ann Chervenak, David W Embley, Henry A. Edinger, Leonidas Fegaras, Dan Forsyth,

Farshad Fotouhi, Michael Franklin, Sreejith Gopinath, Goetz Craefe, Richard Hull,

Sushil [ajodia, Ramesh K Kame, Harish Kotbagi, Vijay Kumar, Tarcisio Lima, RamonA.

Mara-Toledo, Jack McCaw, Dennis McLeod, Rokia Missaoui, Magdi Morsi, M

Naraya-naswamy, Carlos Ordonez, Joan Peckham, Betty Salzberg, Ming-Chien Shan, [unping

Sun, Rajshekhar Sunderraman, Aravindan Veerasamy, and Emilia E Villareal

Last but not l,ast, we gratefully acknowledge the support, encouragement, and

patience of our families

R.E.

S.B.N.

Preface IXIII

PART 1 INTRODUCTION AND CONCEPTUAL MODELING

CHA'1JTER 1 Databases and Database Users 3

1.1 Introduction 4

1.2 An Example 6

1.3 Characteristics of the Database Approach 8

1.4 Actors on the Scene 12

1.5 Workers behind the Scene 14

1.6 Advantages of Using the DBMS Approach 15

1.7 A Brief History of Database Applications 20

1.8 When Not to Use aDBMS 23

2.4 The Database System Environment 35 2.5 Centralized and Client/Server Architectures for DBMSs 38 2.6 Classification of Database Management Systems 43

2.7 Summary 45 Review Questions 46 Exercises 46

3.5 Weak Entity Types 68 3.6 Refining theERDesign for the COMPANYDatabase 69 3.7 ERDiagrams, Naming Conventions, and Design Issues 70 3.8 Notation for UML Class Diagrams 74

3.9 Summary 77 Review Questions 78 Exercises 78

Contents I xvii

4.6 Representing Specialization/Generalization and Inheritance in UML

Class Diagrams 104

4.7 Relationship Types of Degree Higher Than Two 105

4.8 Data Abstraction, Knowledge Representation, and Ontology

PART 2 RELATIONAL MODEL: CONCEPTS, CONSTRAINTS,

LANGUAGES, DESIGN, AND PROGRAMMING

CHAPTER 5 The Relational Data Model and

5.1 Relational Model Concepts 126

5.2 Relational Model Constraints and Relational Database

171

189 185

CHAPTER 6 The Relational Algebra and Relational

6.1 Unary Relational Operations:SELECT and PROJECT

6.2 Relational Algebra Operations from Set Theory

6.3 Binary Relational Operations:JOIN and DIVISION

6.4 Additional Relational Operations 165

6.5 Examples of Queries in Relational Algebra

6.6 The Tuple Relational Calculus 173

6.7 The Domain Relational Calculus 181

6.8 Summary 184

Review Questions

Exercises 186

Selected Bibliography

xviii Contents

CHAPTER 7 Relational Database Design by

7.1 Relational Database Design Using ER-to-Relational Mapping 192

7.2 Mapping EER Model Constructs to Relations 199 7.3 Summary 203

Review Questions 204 Exercises 204

Selected Bibliography 205

CHAPTER 8 sQL 99: Schema Definition,

Basic Constraints, and Queries 207

8.1 SQL Data Definition and Data Types 209 8.2 Specifying Basic Constraints in SQL 213 8.3 Schema Change Statements in SQL 217 8.4 Basic Queries in SQL 218

8.5 More ComplexSQLQueries 229 8.6 Insert, Delete, and Update Statements inSQL 245 8.7 Additional Features ofSQL 248

8.8 Summary 249 Review Questions 251 Exercises 251

9.6 Database Stored Procedures andSQL/PSM 284 9.7 Summary 287

Review Questions 287 Exercises 287

Selected Bibliography 289

PART 3 DATABASE DESIGN THEORY AND METHODOLOGY

CHAPTER 10 Functional Dependencies and

Normalization for Relational Databases 293

10.1 Informal Design Guidelines for Relation Schemas 295

10.2 Functional Dependencies 304

10.3 Normal Forms Based on Primary Keys 312

10.4 General Definitions of Second and Third Normal Forms 320

CHAPTER 11 Relational Database Design

Algorithms and Further Dependencies

11.1 Properties of Relational Decompositions 334

11.2 Algorithmsfor Relational Database Schema Design

11.3 Multivalued Dependencies and Fourth Normal Form

11.4 Join Dependencies and Fifth Normal Form 353

CHAPTER 12 Practical Database Design Methodology

and Use of UML Diagrams 361

12.1 The Role ofInformation Systems in Organizations 362

12.2 The Database Design and Implementation Process 366

12.3 Use ofUML Diagrams as an Aid to Database Design

Specification 385

12.4 Rational Rose, A UML Based Design Tool 395

12.5 Automated Database Design Tools 402

Selected Bibliography 406

415

454 450

CHAPTER 13 Disk Storage, Basic File Structures, and

Hashing 411

13.1 Introduction 412 13.2 Secondary Storage Devices 13.3 Buffering of Blocks 421 13.4 Placing File Records on Disk 13.5 Operations on Files 427 13.6 Files of Unordered Records (Heap Files) 13.7 Files of Ordered Records (Sorted Files)

13.9 Other Primary File Organizations 442 13.10 Parallelizing Disk Access Using RAIDTechnology 13.11 Storage Area Networks 447

Review Questions

Selected Bibliography

CHAPTER 14 Indexing Structures for Files 455

14.1 Types of Single- Level Ordered Indexes 456 14.2 Multilevel Indexes 464

14.3 Dynamic Multilevel Indexes Using B-Trees and W-Trees 469 14.4 Indexes on Multiple Keys 483

14.5 Other Types ofIndexes 485

15.5 Implementing Aggregate Operations and Outer Joins 509

15.6 Combining Operations Using Pipe lining 511

15.7 Using Heuristics in Query Optimization 512

15.8 Using Selectivity and Cost Estimates in Query Optimization 523

15.9 Overview of Query Optimization inORACLE 532

15.10 Semantic Query Optimization 533

15.11 Summary 534

Review Questions 534

Exercises 535

Selected Bibliography 536

CHAPTER 16 Practical Database Design and Tuning 537

16.1 Physical Database Design in Relational Databases 537

16.2 An Overview of Database Tuning in Relational Systems 541

CHAPTER 1 7 Introduction to Transaction

Processing Concepts and Theory

17.1 Introduction to Transaction Processing 552

17.2 Transaction and System Concepts 559

17.3 Desirable Properties of Transactions 562

17.4 Characterizing Schedules Based on Recoverability

17.5 Characterizing Schedules Based on Serializability

CHAPTER 18 Concurrency Control Techniques 583

18.1 Two-Phase Locking Techniques for Concurrency Control 584

18.2 Concurrency Control Based on Timestamp Ordering 594

18.3 Multiversion Concurrency Control Techniques 596

18.4 Validation (Optimistic) Concurrency Control Techniques 599

Selected Bibliography 609

CHAPTER 19 Database Recovery Techniques 611

19.1 Recovery Concepts 612 19.2 Recovery Techniques Based on Deferred Update 618 19.3 Recovery Techniques Based on Immediate Update 622

19A Shadow Paging 624 19.5 TheARIES Recovery Algorithm 625 19.6 Recovery in Multidatabase Systems 629 19.7 Database Backup and Recovery from Catastrophic Failures 630 19.8 Summary 631

Review Questions 632 Exercises 633

Selected Bibliography 635

PART 6 OBJECT AND OBJECT-RELATIONAL DATABASES

CHAPTER 20 Concepts for Object Databases 639

20.1 Overview of Object-Oriented Concepts 641 20.2 Object Identity, Object Structure, and Type Constructors 20.3 Encapsulation of Operations, Methods, and Persistence

20A Type and Class Hierarchies and Inheritance 654 20.5 Complex Objects 657

20.6 Other Objected-Oriented Concepts 659 20.7 Summary 662

Review Questions 663 Exercises 664

Selected Bibliography 664

643 649

CHAPTER 21 Object Database Standards, Languages, and

Design 665

21.1 Overview of the Object Model ofODMG 666

Contents IXX/II

21.2 The Object Definition Language ODL 679

21.3 The Object Query Language OQL 684

21.4 Overview of the c++ Language Binding 693

21.5 Object Database Conceptual Design 694

725 728

CHAPTER 22 Object-Relational and Extended-Relational

Systems 701

22.1 Overview ofSQL and Its Object-Relational Features

22.2 Evolution and Current Trends of Database Technology

22.3 The Informix Universal Server 711

22.4 Object-Relational Features of Oracle 8 721

22.5 Implementation and Related Issues for Extended Type

Systems 724

22.6 The Nested Relational Model

22.7 Summary 727

Selected Bibliography

PART 7 FURTHER TOPICS

CHAPTER 23 Database Security and Authorization 731

23.1 Introduction to Database Security Issues 732

23.2 Discretionary Access Control Based on Granting and Revoking

Privileges 735

23.3 Mandatory Access Control and

Role- Based Access Control for Multilevel Security 740

23.4 Introduction to Statistical Database Security 746

23.5 Introduction to Flow Control 747

23.6 Encryption and Public Key Infrastructures 749

23.7 Summary 751

Review Questions 752

Exercises 753

Selected Bibliography 753