The definitive book on the foundations and theory of database systems, including advanced topics not presented in any other survey book. Includes a comprehensive resource useful for any database researcher or practitioner that covers both fundamental and advanced topics.
Database theory is a relative newcomer to the field of computer science. Early data management systems were based on techniques from several classical areas of computer science, ranging from hardware and operating systems to data structures and programming languages. In the early seventies, a leap of abstraction from file systems produced relational databases and its accompanying theory, with logic as the catalyst.We believe that database theory has matured—that it has emerged as an elegant and robust part of science with its own identity. As such, it embodies its own peculiar brand of wisdom that deserves to be communicated not just to insiders, but to the computer science community at large.
In a nutshell, a database management system is a software system that enables the creation, maintenance, and use of large amounts of data. In contrast with many programming applications, the logical data structure—the “database schema”—used to structure a given data set is usually much smaller than the volume of that set. Furthermore, the data is persistent, evolving over time and surviving multiple invocations of the database management software. To increase usability, concurrent access to the data is usually supported with specialized protocols that guarantee a form of noninterference between interleaved transactions. Importantly, modern database management systems embody a distinction between the logical level and the physical level. The logical level focuses on an abstract representation of the data, along with languages to create, query and modify it; the physical level focuses on the underlying implementation, including the physical layout used to store the data, the indexing and clustering schemes, and the concurrency and recovery protocols.