A Visual Introduction to SQL, 2/e
暫譯: SQL 視覺化入門（第二版）

Learn SQL basics quickly with this visual tutorial featuring over 125 graphics SQL (Structured Query Language) is the tool used to access nearly all databases, which means that most software professionals should understand at least the basics. This hands-on tutorial offers an accessible introduction to SQL using over 125 graphics to illustrate the lessons. The book's unique visual approach makes it much easier for the reader to learn SQL. This Second Edition has been updated with new graphics and covers such subjects as the SELECT statement, joins, subqueries, views, granting and revoking privileges, and creating and destroying tables.

Table of Contents

Foreword.

Preface.

Chapter 1: Introducing SQL.

Kinds of Database Systems.

Relational Concepts.

Tables, Rows, and Columns.

Keys.

An Example Table.

The Visual Approach.

Chapter 2: Elements of the Language.

Ways to Use SQL.

Versions of SQL.

Defining the Language.

Data Types.

The Structure of SQL Statements.

Keywords.

An Example Database.

Organization of the Examples.

Chapter 3: Retrieving Data from a Table: The SELECT Statement.

Selecting Specific Columns in a Table.

Selecting All Columns in a Table.

Selecting Only Some of a Table's Records: The WHERE Clause.

Comparisons in a WHERE Clause.

Combining Predicates in a WHERE Clause.

Using AND.

Using OR.

Using NOT.

Other Uses of WHERE.

BETWEEN and NOT BETWEEN.

LIKE and NOT LIKE.

IN and NOT IN.

IS NULL and IS NOT NULL.

Chapter 4: More on SELECT.

Ordering Selected Data.

Doing Arithmetic with Selected Information.

Using Aggregates.

Finding Maximum and Minimum Values.

Totaling Columns.

Finding Averages.

Counting Records.

Using DISTINCT.

Grouping Selected Data.

More on Grouping: The HAVING Clause.

Chapter 5: Retrieving Data from Several Tables: Joins.

Qualified Names.

What Is a Join?

Restricting the Results of a Join.

Query Diagrams for Joins.

Joining Tables Using the Join Operator.

Manipulating the Results of a Join.

Aliases.

Joins with Three Tables.

The Visual Approach with More Than Two Tables.

Joins with More Than Three Tables.

Retrieving the Same Information in Different Ways.

Using GROUP BY in a Join.

Chapter 6: Queries within Queries: Subqueries.

What Is a Subquery?

Using Comparison Operators with Subqueries.

Using ANY and ALL.

Existence Tests.

Correlated Subqueries.

Using HAVING with Correlated Subqueries.

Chapter 7: Creating and Destroying Tables.

Creating a Table.

Disallowing NULL Values.

Requiring Unique Values in a Column.

Destroying (Dropping) Tables.

Chapter 8: Adding, Modifying, and Deleting Records.

Adding Records to a Table.

Adding Records with Values Only for Some Columns.

Adding Records Using SELECT.

Modifying Records in a Table.

Deleting Records from a Table.

Chapter 9: Views.

Creating Views.

Creating Views Based on One Table.

Creating Views Based on More Than One Table.

Queries Using Views.

Selecting Records from a View.

Adding Records to a View.

Modifying Records in a View.

Deleting Records from a View.

Destroying (Dropping) Views.

Chapter 10: Granting and Revoking Privileges.

Granting Privileges.

Granting Privileges on Views.

Passing Privileges On: The GRANT Option.

Revoking Privileges.

Chapter 11: Advanced Topics.

Indexes.

Creating Indexes.

When to Create Indexes.

Destroying Indexes.

Using Multiple SQL Statements to Solve a Problem.

Outer Joins.

Unions.

Joining a Table with Itself.

Final Thoughts.

Appendix A: The Example Database.

Appendix B: List of Examples.

Appendix C: The Example Database.

Index.