Beginning XML databases

471 Pages·2007·3.295 MB·English

by  Gavin Powell

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Beginning
XML Databases
Gavin Powell
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Beginning XML Databases
Published by
Wiley Publishing, Inc.
10475 Crosspoint Boulevard
Indianapolis, IN 46256
www.wiley.com
Copyright © 2007 by Wiley Publishing, Inc., Indianapolis, Indiana
Published simultaneously in Canada
ISBN-13: 978-0-471-79120-1
ISBN-10: 0-471-79120-2
Manufactured in the United States of America
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Contents
Introduction xvii
Chapter 1: What Is XML? 1
Comparing HTML and XML 2
What Is XML Capable Of? 3
What Is XSL? 3
Creating and Displaying a Simple XML Document 4
Embedding XML in HTML Pages (Data Islands) 7
Introducing the XML Document Object Model 11
XML Browsers and Different Internet Browsers 12
The Document Type Definition 12
XML Syntax 13
Elements 17
Attributes 19
Reserved Characters in XML 24
Ignoring the XML Parser with CDATA 24
What Are XML Namespaces? 24
XML in Many Languages 26
Summary 27
Exercises 27
Chapter 2: The XML Document Object Model 29
Basic XML DOM Structure 30
The Primary XML DOM Classes 32
The Node Class 33
The NodeList Class 34
The NamedNodeMap Class 35
The Document Class 38
The Element Class 42
The Attr Class 44
The Text Class 45
More Obscure XML DOM Classes 47
The parseError Class 47
HTTPRequest Class 50
Other Classes 52
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Generating XML Using ASP 52
Summary 54
Exercises 54
Chapter 3: Extending the Power of XML with XSL 57
What Is XSL? 57
The Roots of XSL 58
Basic XSL Elements Syntax 59
Processing Instruction Elements 60
xsl:processing-instruction 60
xsl:stylesheet 60
xsl:comment 61
xsl:script 61
Transformation Elements 61
xsl:template 61
xsl:apply-templates 64
xsl:call-template 66
Node Creation Elements 66
xsl:element 66
xsl:attribute 67
xsl:copy 67
xls:copy-of 68
Data Retrieval Elements 69
xsl:value-of 69
xsl:output 70
xsl:text 70
Control Structure Elements 70
xsl:if 70
xsl:for-each 71
xsl:choose,xsl:when and xsl:otherwise 72
xsl:sort 74
xsl:variable 75
xsl:param 75
Advanced XSL Syntax 76
Function Versus Method 76
XSL Function Syntax 77
XSL Method Syntax 81
XSL Pattern Matching Syntax 81
Combining the XML DOM and XSL 82
Summary 84
Exercises 85
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Contents
Chapter 4: Relational Database Tables and XML 87
Using SQL for Database Access 88
Queries 89
The SELECT Command 89
The WHERE Clause 92
The ORDER BY Clause 100
The GROUP BY Clause 102
The JOIN Clause 104
Subqueries 110
The UNION Clause 115
Changing Data in a Database 119
Subqueries in Database Change Statements 120
What Is a Transaction? 121
Changing Database Objects 121
Generating XML Pages Using Basic SQL 122
Summary 128
Exercises 129
Chapter 5: Oracle Database and XML 131
The Oracle XMLType Data Type 131
Oracle XMLType Data Type Methods 132
Implementing XML in an Oracle Database 134
Creating XML Documents from an Oracle Database 134
The SQL/XML Standard 135
The SYS_XMLGEN Function 146
PL/SQL and XML 151
XML and the Database 153
New XML Documents 153
Retrieving from XML Documents 154
Using XMLType Methods to Read XML Documents 155
Changing and Removing XML Document Content 159
Summary 161
Exercises 162
Chapter 6: SQL Server and XML 165
The SQL Server XML Data Type 166
SQL Server XML Data Type Methods 168
Generating XML: The FOR XML Clause 169
FOR XML RAW Mode 170
FOR XML AUTO Mode 174
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FOR XML EXPLICIT Mode 179
FOR XML PATH Mode 181
Generating Tuples from XML: OPENXML 183
Working with XML Data Types 185
Adding XML Documents to SQL Server 185
Retrieving and Modifying XML Data Types 186
Defining XML Content with XSD Schemas 191
Strongly Typing XML Documents with XSD 191
Mapping an XSD Schema to a Table 192
Annotating the XSD Script to Enforce Relationships 193
Storing XSD as a Schema Collection 195
Creating Indexes on XML Data Types 199
Summary 202
Exercises 202
Chapter 7: XML in Heterogeneous Environments 205
Basic XML Document Transfer 206
Sharing XML with Web Services 207
The HTTP Protocol 207
Transformation Processing 208
Web Services Protocol 208
Applying Semantics to XML Transfers 209
Simple Object Access Protocol 210
External Data and XML 219
B2B Data Transfer 220
Summary 222
Exercises 222
Chapter 8: Understanding XML Documents as Objects 225
Why Explain the Object Model Here? 225
XML Data as a Relational Structure 226
The Basics of the Object Data Model 230
Creating an Object Model from a Relational Model 232
XML Data as an Object Structure 235
Summary 242
Exercises 242
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Contents
Chapter 9: What Is a Native XML Database? 245
An XML Document Is a Database 246
Defining a Native XML Database 248
Creating a Native XML Database 248
Schema-Less Native XML Database Collections 252
What Is Indexing? 256
Indexing a Native XML Database 258
What About Using XSL and the XML DOM? 259
Classify Native XML Databases by Content 260
Document-Centric XML 260
Data-Centric XML 260
Using a Native XML Database 261
Summary 262
Exercises 262
Chapter 10: Navigating XML Documents Using XPath 265
What Is XPath? 265
Absolute and Relative Paths 266
XPath Nodes 266
XPath Node Relationships 267
XPath Expression Syntax 268
Simple Expressions to Find Nodes 272
Find Specific Values Using Predicates 274
XPath Operators 275
Use Wildcards to Find Unknown Nodes 277
Expressions on Multiple Paths 278
XPath Axes 279
XPath Functions 281
Accessor Functions 282
Errors and Tracing 283
Constructor Functions 283
Numeric Functions 284
String Functions 285
URI Functions 285
Boolean Functions 286
Boolean Operators 286
Functions on Durations,Dates,and Times 286
QName Functions 287
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Node Functions 288
Sequence Functions 288
Context Functions 289
Summary 293
Exercises 293
Chapter 11: Reading XML Documents Using XQuery 295
What Is XQuery? 296
Shared Components 296
The Basics of XQuery 296
Executing XQuery Queries 296
Using Saxon 297
Embedding XQuery Code into HTML 299
XQuery Terminology 302
XQuery Syntax 303
Functions in XQuery 303
XQuery FLWOR 304
FLWOR: The Basic for Loop and Return Clause 304
FLWOR: Adding a where Clause 306
FLWOR: Adding an Order By Clause 307
FLWOR: Declaring Variables with the Let Clause 308
FLWOR: Embedded for Loops and Communication 309
XQuery in Oracle XML DB 311
What Is XQueryX? 312
Summary 313
Exercises 314
Chapter 12: Some Advanced XML Standards 315
XLink and XPointer 316
What Is XLink? 316
Simple XLinks 316
Some More Advanced XLink Attributes 320
Extended XLinks 322
What Is XPointer? 333
XForms and HTML Form Generation 339
The XForms Model 339
XForms Namespaces 340
Other XForms Input Types 342
Data Types in XForms 342
Restricting Values with XForms Properties 343
XForms Object Actions 344
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Built-in and User-Defined Functions 345
Binding Data Using XPath 346
Embedding XML Documents with XInclude 348
Formatting XML Output Using XML-FO 348
Summary 348
Exercises 349
Chapter 13: Data Modeling and XML 351
The Document Type Definition 352
DTD Elements 354
DTD Element Categories 354
DTD Element Content 355
DTD Element Cardinality 357
DTD Attributes 360
Attribute Types 361
Attribute Defaults 362
DTD Entities 364
Built-In Entities and ASCII Code Character Entities 364
Custom and Parameter Entities 365
The XML Schema Definition 370
Global and Local Types 370
Basic XSD Structures 371
XML Schema Data Types 371
Cardinality 373
Element Ordering Sequence and Choice 374
Custom Data Types 375
Substitution 379
Summary 380
Exercises 380
Chapter 14: Applying XML Databases in Industry 381
What Can XML Do? 381
Managing Complex Data with XML 382
Does Database Size Matter? 382
Are Schema Changes Easier with XML? 383
Native XML Databases 384
Specific XML Vocabularies 386
XML Vocabularies 386
Commercial Implementation of XML 392
When to Use a Native XML Database 394
Summary 396
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Contents
Glossary 397
Appendix A: Exercise Answers 419
Appendix B: The Sample Database 427
Appendix C: Syntax Conventions 431
Appendix D: XML Technology 433
Appendix E: XML Relational Database Technology 435
Index 445
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