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Preface
It is our great pleasure to present the thirteenth edition of Database Systems. We are grateful
and humbled that so many of our colleagues around the world have chosen this text to support
their classes. We wrote the first edition of this book because we wanted to explain the complexity
of database systems in a language that was easy for students to understand. Over the years, we
have maintained this emphasis on reaching out to students to explain complex concepts in a
practical, approachable manner. This book has been successful through twelve editions because
the authors, editors, and the publisher paid attention to the impact of technology and to adopters’
questions and suggestions. We believe that this thirteenth edition successfully reflects the same
attention to such factors.
In many respects, rewriting a book is more difficult than writing it the first time. If the book is
successful, as this one is, a major concern is that the updates, inserts, and deletions will adversely
affect writing style and continuity of coverage. The combination of superb reviewers and editors,
plus a wealth of feedback from adopters and students of the previous editions, helped make this
new edition the best yet.
Changes to the Thirteenth Edition
In this thirteenth edition, we have responded to the requests and suggestions of numerous adopt-
ers. We have substantially reorganized the SQL coverage to make the presentation easier to fol-
low and easier to reference. We start with simple SQL statements to familiarize students with the
basic SQL syntax and environment. This provides students the confidence to transition to the
more advanced SQL features and commands. These changes provide a better flow of material.
Additionally, more SQL examples and figures have been added to help students better visualize
and understand the code that is presented.
Aside from enhancing the already strong coverage of database design, we made other improve-
ments in the topical coverage. In particular, the continued growth of Big Data and NoSQL tech-
nologies continue to challenge the status quo in the database industry. Therefore, we have added
two new online appendices on MongoDB and Neo4j, two of the most important of the NoSQL
offerings. This new material provides coding examples and data files to allow students to gain
hands-on experience using two of the most popular NoSQL databases. The thirteenth edition
also presents a major step forward in the integration of digital content with the text through
online, automatically graded coding labs that allow students to write SQL code in an interactive
environment that can grade and provide feedback on problems. Here are a few of the highlights
of changes in the thirteenth edition:
• Streamlined and reorganized coverage of normalization for enhanced clarity
• Complete reorganization of SQL and Advanced SQL chapters to improve flow and make ref-
erences to keywords and techniques easier to access
• Expanded coverage of MongoDB with hands-on exercises for querying MongoDB databases
(Appendix P)
• Expanded coverage of Neo4j with hands-on exercises for querying graph databases using
Cypher (Appendix Q)
• New and expanded coverage of data visualization tools and techniques
This thirteenth edition continues to provide a solid and practical foundation for the design,
implementation, and management of database systems. This foundation is built on the notion
that, while databases are very practical, their successful creation depends on understanding the
important concepts that define them. It’s not easy to come up with the proper mix of theory and
practice, but the previously mentioned feedback suggests that we largely succeeded in our quest
to maintain the proper balance.
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Copyright 2019 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. WCN 02-200-203