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| Foreword | |
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| Preface | |
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| About the Authors | |
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| Introduction | |
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| Are You a Mere Mortal? | |
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| About This Book | |
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| What This Book Is Not | |
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| How to Use This Book | |
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| Reading the Diagrams Used in This Book | |
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| Sample Databases Used in This Book | |
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| "Follow the Yellow Brick Road" | |
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| Relational Databases and SQL | |
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| What Is Relational? | |
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| Topics Covered in This Chapter | |
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| Types of Databases | |
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| A Brief History of the Relational Model | |
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| Anatomy of a Relational Database | |
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| What's in It for You? | |
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| Where Do You Go from Here? | |
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| Summary | |
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| Ensuring Your Database Structure Is Sound | |
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| Topics Covered in This Chapter | |
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| Why Is This Chapter Here? | |
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| Why Worry about Sound Structures? | |
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| Fine-Tuning Fields | |
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| Fine-Tuning Tables | |
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| Establishing Solid Relationships | |
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| Is That All? | |
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| Summary | |
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| A Concise History of SQL | |
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| Topics Covered in This Chapter | |
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| The Origins of SQL | |
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| Early Vendor Implementations | |
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| ". . . And Then There Was a Standard" | |
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| Evolution of the ANSI/ISO Standard | |
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| Commercial Implementations | |
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| What the Future Holds | |
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| Why Should You Learn SQL? | |
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| Summary | |
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| SQL Basics | |
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| Creating a Simple Query | |
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| Topics Covered in This Chapter | |
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| Introducing SELECT | |
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| The SELECT Statement | |
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| A Quick Aside: Data versus Information | |
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| Translating Your Request into SQL | |
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| Eliminating Duplicate Rows | |
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| Sorting Information | |
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| Saving Your Work | |
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| Sample Statements | |
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| Summary | |
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| Problems for You to Solve | |
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| Getting More Than Simple Columns | |
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| Topics Covered in This Chapter | |
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| What Is an Expression? | |
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| What Type of Data Are You Trying to Express? | |
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| Changing Data Types: The CAST Function | |
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| Specifying Explicit Values | |
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| Types of Expressions | |
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| Using Expressions in a SELECT Clause | |
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| That "Nothing" Value: Null | |
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| Sample Statements | |
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| Summary | |
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| Problems for You to Solve | |
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| Filtering Your Data | |
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| Topics Covered in This Chapter | |
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| Refining What You See Using WHERE | |
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| Defining Search Conditions | |
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| Using Multiple Conditions | |
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| Nulls Revisited: A Cautionary Note | |
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| Expressing Conditions in Different Ways | |
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| Sample Statements | |
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| Summary | |
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| Problems for You to Solve | |
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| Working with Multiple Tables | |
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| Thinking in Sets | |
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| Topics Covered in This Chapter | |
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| What Is a Set, Anyway? | |
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| Operations on Sets | |
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| Intersection | |
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| Difference | |
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| Union | |
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| SQL Set Operations | |
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| Summary | |
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| Inner Joins | |
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| Topics Covered in This Chapter | |
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| What Is a JOIN? | |
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| The Inner Join | |
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| Uses for Inner Joins | |
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| Sample Statements | |
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| Summary | |
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| Problems for You to Solve | |
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| Outer Joins | |
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| Topics Covered in This Chapter | |
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| What Is an Outer Join? | |
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| The Left/Right Outer Join | |
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| The Full Outer Join | |
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| Uses for Outer Joins | |
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| Sample Statements | |
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| Summary | |
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| Problems for You to Solve | |
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| Unions | |
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| Topics Covered in This Chapter | |
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| What Is a Union? | |
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| Writing Requests with Union | |
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| Uses for Union | |
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| Sample Statements | |
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| Summary | |
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| Problems for You to Solve | |
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| Subqueries | |
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| Topics Covered in This Chapter | |
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| What Is a Subquery? | |
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| Subqueries as Column Expressions | |
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| Subqueries as Filters | |
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| Uses for Subqueries | |
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| Sample Statements 394 Summary | |
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| Problems for You to Solve | |
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| Summarizing and Grouping Data | |
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| Simple Totals | |
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| Topics Cover | |