The ?rst International Symposium on the Applications of Constraint Databases (CDB2004) took place in Paris, France, on June 12–13, 2004, just before the ACM SIGMOD and PODS conferences. Since the publication of the paper “Constraint Query Languages” by Kan- lakis, Kuper and Revesz in 1990, the last decade has seen a growing interest in constraint database theory, query evaluation, and applications, re?ected in a variety of conferences, journals, and books. Constraint databases have proven to be extremely ?exible and adoptable in environments that relational database systems cannot serve well, such as geographic information systems and bioinf- matics. This symposium brought together people from several diverse areas all c- tributing to the practice and the application of constraint databases. It was a continuation and extension of previous workshops held in Friedrichshafen, G- many (1995), Cambridge, USA (1996), Delphi, Greece (1997), and Seattle, USA (1998) as well as of the work in the comprehensive volume “Constraint Data- ses” edited by G. Kuper, L. Libkin and J. Paredaens (2000) and the textbook “Introduction to Constraint Databases” by P. Revesz (2002). The aim of the symposium was to open new and future directions in c- straint database research; to address constraints over domains other than the reals; to contribute to a better implementation of constraint database systems, in particular of query evaluation; to address e?cient quanti?er elimination; and to describe applications of constraint databases.

Differing from other books on the subject, this one uses the framework of constraint databases to provide a natural and powerful generalization of relational databases. An important theme running through the text is showing how relational databases can smoothly develop into constraint databases, without sacrificing any of the benefits of relational databases whilst gaining new advantages. Peter Revesz begins by discussing data models and how queries may be addressed to them. From here, he develops the theory of relational and constraint databases, including Datalog and the relational calculus, concluding with three sample constraint database systems -- DISCO, DINGO, and RATHER. Advanced undergraduates and graduates in computer science will find this a clear introduction to the subject, while professionals and researchers will appreciate this novel perspective on their subject.

This is the first comprehensive survey of the field of constraint databases, written by leading researchers. Constraint databases are a fairly new and active area of database research. Their ability to deal with infinite sets makes them particularly promising as a technology for integrating spatial and temporal data with standard relational databases. Constraint databases bring techniques from a variety of fields, such as logic and model theory, algebraic and computational geometry, as well as symbolic computation, to the design and analysis of data models and query languages.

What does it take to develop an enterprise application with Rails? Enterprise Rails introduces several time-tested software engineering principles to prepare you for the challenge of building a high-performance, scalable website with global reach. You'll learn how to design a solid architecture that ties the many parts of an enterprise website together, including the database, your servers and clients, and other services as well. Many Rails developers think that planning for scale is unnecessary. But there's nothing worse than an application that fails because it can't handle sudden success. Throughout this book, you'll work on an example enterprise project to learn first-hand what's involved in architecting serious web applications. With this book, you will: Tour an ideal enterprise systems layout: how Rails fits in, and which elements don't rely on Rails Learn to structure a Rails 2.0 application for complex websites Discover how plugins can support reusable code and improve application clarity Build a solid data model -- a fortress -- that protects your data from corruption Base an ActiveRecord model on a database view, and build support for multiple table inheritance Explore service-oriented architecture and web services with XML-RPC and REST See how caching can be a dependable way to improve performance Building for scale requires more work up front, but you'll have a flexible website that can be extended easily when your needs change. Enterprise Rails teaches you how to architect scalable Rails applications from the ground up. "Enterprise Rails is indispensable for anyone planning to build enterprise web services. It's one thing to get your service off the ground with a framework like Rails, but quite another to construct a system that will hold up at enterprise scale. The secret is to make good architectural choices from the beginning. Chak shows you how to make those choices. Ignore his advice at your peril."-- Hal Abelson, Prof. of Computer Science and Engineering, MIT

This is the first comprehensive survey of the field of constraint databases, written by leading researchers. Constraint databases are a fairly new and active area of database research. Their ability to deal with infinite sets makes them particularly promising as a technology for integrating spatial and temporal data with standard relational databases. Constraint databases bring techniques from a variety of fields, such as logic and model theory, algebraic and computational geometry, as well as symbolic computation, to the design and analysis of data models and query languages.

Constraints and Databases contains seven contributions on the rapidly evolving research area of constraints and databases. This collection of original research articles has been compiled as a tribute to Paris C. Kanellakis, one of the pioneers in the field. Constraints have long been used for maintaining the integrity of databases. More recently, constraint databases have emerged where databases store and manipulate data in the form of constraints. The generality of constraint databases makes them highly attractive for many applications. Constraints provide a uniform mechanism for describing heterogenous data, and advanced constraint solving methods can be used for efficient manipulation of constraint data. The articles included in this book cover the range of topics involving constraints and databases; join algorithms, evaluation methods, applications (e.g. data mining) and implementations of constraint databases, as well as more traditional topics such as integrity constraint maintenance. Constraints and Databases is an edited volume of original research comprising invited contributions by leading researchers.

Deductive Databases and their Applications is an introductory text aimed at undergraduate students with some knowledge of database and information systems. The text comes complete with exercises and solutions to encourage students to tackle problems practically as well as theoretically. The author presents the origins of deductive databases in Prologue before proceeding to analyse the main deductive database paradigm - the data-log model. The final chapters are dedicated to closely related topics such as prepositional expert systems, integrity constraint specification and evaluation, and update propagation. Particular attention is paid to CASE tool repositories.

Time is ubiquitous in information systems. Almost every enterprise faces the problem of its data becoming out of date. However, such data is often valu able, so it should be archived and some means to access it should be provided. Also, some data may be inherently historical, e.g., medical, cadastral, or ju dicial records. Temporal databases provide a uniform and systematic way of dealing with historical data. Many languages have been proposed for tem poral databases, among others temporal logic. Temporal logic combines ab stract, formal semantics with the amenability to efficient implementation. This chapter shows how temporal logic can be used in temporal database applica tions. Rather than presenting new results, we report on recent developments and survey the field in a systematic way using a unified formal framework [GHR94; Ch094]. The handbook [GHR94] is a comprehensive reference on mathematical foundations of temporal logic. In this chapter we study how temporal logic is used as a query and integrity constraint language. Consequently, model-theoretic notions, particularly for mula satisfaction, are of primary interest. Axiomatic systems and proof meth ods for temporal logic [GHR94] have found so far relatively few applications in the context of information systems. Moreover, one needs to bear in mind that for the standard linearly-ordered time domains temporal logic is not re cursively axiomatizable [GHR94]' so recursive axiomatizations are by necessity incomplete.

"Addresses the evolution of database management, technologies and applications along with the progress and endeavors of new research areas."--P. xiii.