SQL and Relational Theory

SQL and Relational Theory PDF Author: C. Date
Publisher: "O'Reilly Media, Inc."
ISBN: 1449316409
Category : Computers
Languages : en
Pages : 447

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Book Description
SQL is full of difficulties and traps for the unwary. You can avoid them if you understand relational theory, but only if you know how to put the theory into practice. In this insightful book, author C.J. Date explains relational theory in depth, and demonstrates through numerous examples and exercises how you can apply it directly to your use of SQL. This second edition includes new material on recursive queries, “missing information” without nulls, new update operators, and topics such as aggregate operators, grouping and ungrouping, and view updating. If you have a modest-to-advanced background in SQL, you’ll learn how to deal with a host of common SQL dilemmas. Why is proper column naming so important? Nulls in your database are causing you to get wrong answers. Why? What can you do about it? Is it possible to write an SQL query to find employees who have never been in the same department for more than six months at a time? SQL supports “quantified comparisons,” but they’re better avoided. Why? How do you avoid them? Constraints are crucially important, but most SQL products don’t support them properly. What can you do to resolve this situation? Database theory and practice have evolved since the relational model was developed more than 40 years ago. SQL and Relational Theory draws on decades of research to present the most up-to-date treatment of SQL available. C.J. Date has a stature that is unique within the database industry. A prolific writer well known for the bestselling textbook An Introduction to Database Systems (Addison-Wesley), he has an exceptionally clear style when writing about complex principles and theory.

SQL and Relational Theory

SQL and Relational Theory PDF Author: C. Date
Publisher: "O'Reilly Media, Inc."
ISBN: 1449316409
Category : Computers
Languages : en
Pages : 447

Get Book

Book Description
SQL is full of difficulties and traps for the unwary. You can avoid them if you understand relational theory, but only if you know how to put the theory into practice. In this insightful book, author C.J. Date explains relational theory in depth, and demonstrates through numerous examples and exercises how you can apply it directly to your use of SQL. This second edition includes new material on recursive queries, “missing information” without nulls, new update operators, and topics such as aggregate operators, grouping and ungrouping, and view updating. If you have a modest-to-advanced background in SQL, you’ll learn how to deal with a host of common SQL dilemmas. Why is proper column naming so important? Nulls in your database are causing you to get wrong answers. Why? What can you do about it? Is it possible to write an SQL query to find employees who have never been in the same department for more than six months at a time? SQL supports “quantified comparisons,” but they’re better avoided. Why? How do you avoid them? Constraints are crucially important, but most SQL products don’t support them properly. What can you do to resolve this situation? Database theory and practice have evolved since the relational model was developed more than 40 years ago. SQL and Relational Theory draws on decades of research to present the most up-to-date treatment of SQL available. C.J. Date has a stature that is unique within the database industry. A prolific writer well known for the bestselling textbook An Introduction to Database Systems (Addison-Wesley), he has an exceptionally clear style when writing about complex principles and theory.

Time and Relational Theory

Time and Relational Theory PDF Author: C.J. Date
Publisher: Morgan Kaufmann
ISBN: 0128006757
Category : Computers
Languages : en
Pages : 560

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Book Description
Time and Relational Theory provides an in-depth description of temporal database systems, which provide special facilities for storing, querying, and updating historical and future data. Traditionally, database management systems provide little or no special support for temporal data at all. This situation is changing because: Cheap storage enables retention of large volumes of historical data in data warehouses Users are now faced with temporal data problems, and need solutions Temporal features have recently been incorporated into the SQL standard, and vendors have begun to add temporal support to their DBMS products Based on the groundbreaking text Temporal Data & the Relational Model (Morgan Kaufmann, 2002) and new research led by the authors, Time and Relational Theory is the only book to offer a complete overview of the functionality of a temporal DBMS. Expert authors Nikos Lorentzos, Hugh Darwen, and Chris Date describe an approach to temporal database management that is firmly rooted in classical relational theory and will stand the test of time. This book covers the SQL:2011 temporal extensions in depth and identifies and discusses the temporal functionality still missing from SQL. Understand how the relational model provides an ideal basis for taming the complexities of temporal databases Learn how to analyze and evaluate commercial temporal products with this timely and important information Be able to use sound principles in designing and using temporal databases Understand the temporal support recently added to SQL with coverage of the new SQL features in this unique, accurate, and authoritative reference Appreciate the benefits of a truly relational approach to the problem with this clear, user friendly presentation

Database Design and Relational Theory

Database Design and Relational Theory PDF Author: C. J. Date
Publisher: "O'Reilly Media, Inc."
ISBN: 1449328016
Category : Computers
Languages : en
Pages : 277

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Book Description
Because databases often stay in production for decades, careful design is critical to making the database serve the needs of your users over years, and to avoid subtle errors or performance problems. In this book, C.J. Date, a leading exponent of relational databases, lays out the principles of good database design.

Database in Depth

Database in Depth PDF Author: C.J. Date
Publisher: "O'Reilly Media, Inc."
ISBN: 0596100124
Category : Computers
Languages : en
Pages : 234

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Book Description
This concise guide sheds light on the principles behind the relational model, which underlies all database products in wide use today. It goes beyond the hype to give you a clear view of the technology -- a view that's not influenced by any vendor or product. Suitable for experienced database developers and designers.

E. F. Codd and Relational Theory, Revised Edition

E. F. Codd and Relational Theory, Revised Edition PDF Author: C. J. Date
Publisher: Technics Publications
ISBN: 1634629302
Category : Computers
Languages : en
Pages : 307

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Book Description
E. F. Codd’s relational model of data has been described as one of the three greatest inventions of all time (the other two being agriculture and the scientific method), and his receipt of the 1981 ACM Turing Award, the top award in computer science, for inventing it was thoroughly deserved. The papers in which Codd first described his model were staggering in their originality; they had, and continue to have, a huge impact on just about every aspect of the way we do business in the world today. And yet few people, even in the professional database community, are truly familiar with those papers. This book—a thorough overhaul and rewrite of an earlier book by the same name—is an attempt to remedy this sorry state of affairs. In it, well known author C. J. Date provides a detailed examination of all of Codd’s major database publications, explaining the nature of his contribution in depth, and in particular highlighting not only the many things he got right but also some of the things he got wrong. Database theory and practice have evolved considerably since Codd first defined his relational model, back in 1969. This book draws on decades of experience to present the most up to date treatment of the material possible. Anyone with a professional interest in databases can benefit from the insights it contains. The book is product independent.

SQL and Relational Basics

SQL and Relational Basics PDF Author: Fabian Pascal
Publisher: M & T Books
ISBN: 9781558510630
Category : Computers
Languages : en
Pages : 336

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Book Description
Pascal educates PC users on the true meaning and usefulness of relational database management. Topics include a thorough explanation of the relational model, a clarification of the twelve fidelity rules, an overview of SQL components, and more.

View Updating and Relational Theory

View Updating and Relational Theory PDF Author: C.J. Date
Publisher: "O'Reilly Media, Inc."
ISBN: 1449357806
Category : Computers
Languages : en
Pages : 260

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Book Description
Views are virtual tables. That means they should be updatable, just as "real" or base tables are. In fact, view updatability isn’t just desirable, it’s crucial, for practical reasons as well as theoretical ones. But view updating has always been a controversial topic. Ever since the relational model first appeared, there has been widespread skepticism as to whether (in general) view updating is even possible. In stark contrast to this conventional wisdom, this book shows how views, just like base tables, can always be updated (so long as the updates don’t violate any integrity constraints). More generally, it shows how updating always ought to work, regardless of whether the target is a base table or a view. The proposed scheme is 100% consistent with the relational model, but rather different from the way updating works in SQL products today. This book can: Help database products improve in the future Help with a "roll your own" implementation, absent such product improvements Make you aware of the crucial role of predicates and constraints Show you how relational products are really supposed to behave Anyone with a professional interest in the relational model, relational technology, or database systems in general can benefit from this book.

SQL and Relational Theory

SQL and Relational Theory PDF Author: C.J. Date
Publisher: "O'Reilly Media, Inc."
ISBN: 1491941138
Category : Computers
Languages : en
Pages : 582

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Book Description
SQL is full of difficulties and traps for the unwary. You can avoid them if you understand relational theory, but only if you know how to put that theory into practice. In this book, Chris Date explains relational theory in depth, and demonstrates through numerous examples and exercises how you can apply it to your use of SQL. This third edition has been revised, extended, and improved throughout. Topics whose treatment has been expanded include data types and domains, table comparisons, image relations, aggregate operators and summarization, view updating, and subqueries. A special feature of this edition is a new appendix on NoSQL and relational theory. Could you write an SQL query to find employees who have worked at least once in every programming department in the company? And be sure it’s correct? Why is proper column naming so important? Nulls in the database cause wrong answers. Why? What you can do about it? How can image relations help you formulate complex SQL queries? SQL supports "quantified comparisons," but they’re better avoided. Why? And how? Database theory and practice have evolved considerably since Codd first defined the relational model, back in 1969. This book draws on decades of experience to present the most up to date treatment of the material available anywhere. Anyone with a modest to advanced background in SQL can benefit from the insights it contains. The book is product independent.

The Theory of Relational Databases

The Theory of Relational Databases PDF Author: David Maier
Publisher: Rockville, Md. : Computer Science Press
ISBN:
Category : Computers
Languages : en
Pages : 664

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Book Description
This remarkably comprehensive new book assembles concepts and results in relational databases theory previously scattered through journals, books, conference proceedings, and technical memoranda in one convenient source, and introduces pertinent new material not found elsewhere. The book is intended for a second course in databases, but is an excellent reference for researchers in the field. The material covered includes relational algebra, functional dependencies, multivalued and join dependencies, normal forms, tableaux and the chase computation, representation theory, domain and tuple relational calculus, query modification, database semantics and null values, acyclic database schemes, template dependencies, and computed relations. The final chapter is a brief survey of query languages in existing relational systems. Each chapter contains numerous examples and exercises, along with bibliographic remarks. - Back cover.

Theory and Practice of Relational Databases

Theory and Practice of Relational Databases PDF Author: Stefan Stanczyk
Publisher: CRC Press
ISBN: 0203164563
Category : Computers
Languages : en
Pages : 264

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Book Description
The study of relationship databases is a core component of virtually every undergraduate computer science degree course. This new edition of Theory and Practice of Relationship Databases retains all the features that made the previous edition such as success, and goes on to give even more comprehensive and informative coverage. Written in a tutorial style and containing a great many examples and exercises as well as extensively using illustrative and explanatory graphics, the author has produced an undergraduate textbook of great depth and clarity that is very easy to follow. The subject of relational databases is brought to life by the writing style and the inclusion of an homogenous case study that reinforces the issues dealt with in each chapter. The primary objective of the book is to present a comprehensive explanation of the process of development of database application systems within the framework of a set processing paradigm. Since the majority of these applications are built as relationship systems, a complete though reasonably concise account of that model is presented. Dr. Stanczyk has achieved this by concentrating on the issues that contribute significantly to the application development while de-emphasizing purely theoretical aspects of the subject. This has led to an imaginative and highly practical textbook that will be an excellent read for the undergraduate computer science student.