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Foreword xvii Preface xix About the Authors xxi Introduction xxiii Are You a Mere Mortal? xxiii About This Book xxiv What This Book Is Not xxvi How to Use This Book xxvi Reading the Diagrams Used in This Book xxvii Sample Databases Used in This Book xxxi "Follow the Yellow Brick Road" xxxiii
Part I Relational Databases and SQL 1
Chapter 1 What Is Relational? 3 Types of Databases 3 A Brief History of the Relational Model 4 In the Beginning
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. 4 Relational Database Systems 5 Anatomy of a Relational Database 7 Tables 7 Fields 9 Records 9 Keys 9 Views 11 Relationships 12 What''s in It for You? 17 Where Do You Go from Here? 18 Summary 19
Chapter 2 Ensuring Your Database Structure Is Sound 21 Why Is This
Chapter Here? 21 Why Worry about Sound Structures? 22 Fine-Tuning Fields 23 What''s in a Name? (
Part One) 23 Smoothing Out the Rough Edges 25 Resolving Multipart Fields 27 Resolving Multivalued Fields 30 Fine-Tuning Tables 32 What''s in a Name? (
Part Two) 33 Ensuring a Sound Structure 35 Resolving Unnecessary Duplicate Fields 36 Identification Is the Key 42 Establishing Solid Relationships 45 Establishing a Deletion Rule 48 Setting the Type of Participation 49 Setting the Degree of Participation 52 Is That All? 54 Summary 55
Chapter 3 A Concise History of SQL 57 The Origins of SQL 58 Early Vendor Implementations 59 ".
.
. And Then There Was a Standard" 60 Evolution of the ANSI/ISO Standard 62 Other SQL Standards 65 Commercial Implementations 68 What the Future Holds 69 Why Should You Learn SQL? 69 Which Version of SQL Does This Book Cover? 70 Summary 70
Part II SQL Basics 73
Chapter 4 Creating a Simple Query 75 Introducing SELECT 76 The SELECT Statement 77 A Quick Aside: Data versus Information 79 Translating Your Request into SQL 81 Expanding the Field of Vision 85 Using a Shortcut to Request All Columns 87 Eliminating Duplicate Rows 88 Sorting Information 91 First Things First: Collating Sequences 92 Let''s Now Come to Order 93 Saving Your Work 96 Sample Statements 97 Summary 106 Problems for You to Solve 107
Chapter 5 Getting More Than Simple Columns 109 What Is an Expression? 110 What Type of Data Are You Trying to Express? 111 Changing Data Types: The CAST Function 114 Specifying Explicit Values 116 Character String Literals 116 Numeric Literals 118 Datetime Literals 119 Types of Expressions 121 Concatenation 122 Mathematical Expressions 125 Date and Time Arithmetic 129 Using Expressions in a SELECT Clause 133 Working with a Concatenation Expression 134 Naming the Expression 135 Working with a Mathematical Expression 137 Working with a Date Expression 138 A Brief Digression: Value Expressions 139 That "Nothing" Value: Null 141 Introducing Null 142 The Problem with Nulls 143 Sample Statements 144 Summary 153 Problems for You to Solve 154
Chapter 6 Filtering Your Data 157 Refining What You See Using WHERE 157 The WHERE Clause 158 Using a WHERE Clause 160 Defining Search Conditions 162 Comparison 163 Range 170 Set Membership 173 Pattern Match 175 Null 179 Excluding Rows with NOT 181 Using Multiple Conditions 184 Introducing AND and OR 185 Excluding Rows: Take Two 191 Order of Precedence 193 Checking for Overlapping Ranges 197 Nulls Revisited: A Cautionary Note 199 Expressing Conditions in Different Ways 203 Sample Statements 204 Summary 212 Problems for You to Solve 213
Part III Working with Multiple Tables 217
Chapter 7 Thinking in Sets 219 What Is a Set, Anyway? 220 Operations on Sets 221 Intersection 222 Intersection in Set Theory 222 Intersection between Result Sets 224 Problems You Can Solve with an Intersection 227 Difference 228 Difference in Set Theory 228 Difference between Result Sets 230 Problems You Can Solve with Difference 233 Union 234 Union in Set Theory 234 Combining Result Sets Using a Union 236 Problems You Can Solve with Union 238 SQL Set Operations 239 Classic Set Operations versus SQL 239 Finding Common Values: INTERSECT 240 Finding Missing Values: EXCEPT (DIFFERENCE) 243 Combining Sets: UNION 245 Summary 248
Chapter 8 INNER JOINs 249 What Is a JOIN? 249 The INNER JOIN 250 What''s "Legal" to JOIN? 250 Column References 251 Syntax 252 Check Those Relationships! 267 Uses for INNER JOINs 268 Find Related Rows 268 Find Matching Values 269 Sample Statements 269 Two Tables 270 More Than Two Tables 276 Looking for Matching Values 283 Summary 294

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