This volume represents the outcome of the International Conference on "Extending Database Technology," held in Venice, Italy, in March 1988. It contains the major dimensions into which database technology is currently being pushed by the needs of new applications and pulled by the chances of novel developments in hardware and systems architecture. The two broad areas covered are: extended database semantics: data models and data types, databases and logic, complex objects, and expert system approaches to databases; and new architectures and increased database systems support: novel...

After a long period of research, development, test and trial, relational database management systems are at last being marketed in force. The feedback from early installations of these systems is overwhelmingly positive. The most frequent comment by users is that productivity has been increased by a significant factor (from 5 to 20 times what it was using previous approaches). Another comment is that, in many cases, end users can now handle their own problems by direct use of the system instead of using application programmers as mediators between them and the system. As the reputation of...

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...