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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,...

No matter what DBMS you are using--Oracle, DB2, SQL Server, MySQL, PostgreSQL--misunderstandings can always arise over the precise meanings of terms, misunderstandings that can have a serious effect on the success of your database projects. For example, here are some common database terms: attribute, BCNF, consistency, denormalization, predicate, repeating group, join dependency. Do you know what they all mean? Are you sure?

The New Relational Database Dictionary defines all of these terms and many, many more. Carefully reviewed...

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...

What makes this book different from others on database design? Many resources on design practice do little to explain the underlying theory, and books on design theory are aimed primarily at theoreticians. In this book, renowned expert Chris Date bridges the gap by introducing design theory in ways practitioners can understand--drawing on lessons learned over four decades of experience to demonstrate why proper database design is so critical in the first place.

Every chapter includes a set of exercises that show how to apply the theoretical ideas in practice, provide additional...

All of today s mainstream database products support the SQL language, and relational theory is what SQL is supposed to be based on. But are those products truly relational? Sadly, the answer is no. This book shows you what a real relational product would be like, and how and why it would be so much better than what s currently available.

With this unique book, you will:

• Learn how to see database systems as programming systems
• Get a careful, precise, and detailed definition of the relational model
• Explore a detailed analysis of SQL from a relational point...

This book sheds light on the principles behind the relational model, which is fundamental to all database-backed applications--and, consequently, most of the work that goes on in the computing world today. Database in Depth: The Relational Model for Practitioners goes beyond the hype and gets to the heart of how relational databases actually work.Ideal for experienced database developers and designers, this concise guide gives you a clear view of the technology--a view that's not influenced by any vendor or product. Featuring an extensive set of exercises, it will help you:...