Based on the proceedings of a workshop held at the Appin in August 1985, this book discusses the issues of data abstraction. It introduces the concept of inheritance as a method of polymorphic modelling. It also discusses the issues of controlled access to large scale data in a concurrent and distributed persistent environment.

The growing demand for systems of ever-increasing complexity and precision has stimulated the need for higher level concepts, tools, and techniques in every area of Computer Science. Some of these areas, in particular Artificial Intelligence, Databases, and Programming Lan guages, are attempting to meet this demand by defining a new, more abstract level of system description. We call this new level conceptual in recognition of its basic conceptual nature. In Artificial Intelligence, the problem of designing an expert system is seen primarily as a problem of building a knowledge base that...

This book is an anthology of the results of research and development in database query processing during the past decade. The relational model of data provided tremendous impetus for research into query processing. Since a relational query does not specify access paths to the stored data, the database management system (DBMS) must provide an intelligent query-processing subsystem which will evaluate a number of potentially efficient strategies for processing the query and select the one that optimizes a given performance measure. The degree of sophistication of this subsystem, often called...

The term "Office Automation" implies much and means little. The word "Office" is usually reserved for units in an organization that have a rather general function. They are supposed to support different activities, but it is notoriously difficult to determine what an office is supposed to do. Automation in this loose context may mean many different things. At one extreme, it is nothing more than giving people better tools than typewriters and telephones with which to do their work more efficiently and effectively. At the opposite extreme, it implies the replacement of people by machines which...

Information systems are large repositories of factual and inferential knowledge intended to be queried and maintained by a wide variety of users with different backgrounds and work tasks. The community of potential information system users is growing rapidly with advances in hardware and software technology that permit computer/communications support for more and more application areas. Unfortunately, it is often felt that progress in user interface technology has not quite matched that of other areas. Technical solutions such as computer graphics, natural language processing, or...

In the past, applied artificial intelligence systems were built with particular emphasis on general reasoning methods intended to function efficiently, even when only relatively little domain-specific knowledge was available. In other words, AI technology aimed at the processing of knowledge stored under comparatively general representation schemes. Nowadays, the focus has been redirected to the role played by specific and detailed knowledge, rather than to the reasoning methods themselves. Many new application systems are centered around knowledge bases, i. e., they are based on large...

Object-oriented database systems have been approached with mainly two major intentions in mind, namely to better support new application areas including CAD/CAM, office automation, knowledge engineering, and to overcome the impendance mismatch' between data models and programming languages. This volume gives a comprehensive overwiew of developments in this flourishing area of current database research. Data model and language aspects, interface and database design issues, architectural and implementation questions are covered. Although based on a series of workshops, the contents of this book...

There is a growing interest in integrating databases and programming languages. In recent years the programming language community has developed new models of computation such as logic programming, object-oriented programming and functional programming, to add to the well established von Neumann model. The data base community has almost independently developed more and more sophisticated data models to solve the problems of large scale data organisation. To make use of these new models in programming languages there must be an awareness of the problems of large scale data. The data base...

Current experimental systems in industry, government, and the military take advantage of knowledge-based processing. For example, the Defense Advanced Research Projects Agency (DARPA), and the United States Geological Survey (USGS) are supporting the develop- ment of information systems that contain diverse, vast, and growing repositories of data (e.g., vast databases storing geographic informa- tion). These systems require powerful reasoning capabilities and pro- cessing such as data processing, communications, and multidisciplinary of such systems will scientific analysis. The number and...