Nobuyoshi Miyazaki

A relational database machine with large semiconductor disk and hardware relational algebra processor

This paper describes the basic concepts, design and implementation decisions, standpoints and significance of the database machine Delta in the scope of Japan’s Fifth Generation Computer Project. Delta is planned to be operational in 1985 for researchers’ use as a backend database machine for logic programming software development. Delta is basically a relational database machine system. It combines hardware facilities for efficient relational database operations, which are typically represented by relational algebra, and software which deals with hardware control and actual database management requirements. Notable features include attribute-based internal schema in accordance with the characteristics found in the relation access from logic programming environment. This is also useful for the hardware relational algebra manipulation algorithm based on merge-sorting of attributes by hardware and a large capacity Semiconductor Disk for fast access to databases. Various implementation decisions of database management requirements are made in this novel system configuration, which will be meaningful to give an example for constructing a hardware and software combination of a relational database machine. Delta is in the stage between detailed design and implementation.

An enhanced inference mechanism for generating relational algebra queries

A system for interfacing Prolog programs with relational algebra is presented. The system produces relational algebra queries using a deferred evaluation approach. Least fixed point (LFP) queries are automatically managed. An optimization method for removing redundant relations is also presented.

The Design and Implementation of Relational Database Machine Delta

Delta is relational database machine under development at ICOT. It has specially designed hardware components to perform relational database operations and a large semiconductor memory to be used as disk cache area. The machine will be used in an experimental local area network environment along with Personal Sequential Inference Machines which are also being developed at ICOT. This paper describes design decisions concerning Delta’s architecture and processing algorithms, as well as its overall functions. Delta is expected to be operational with a data storage capacity of 20 GB by March, 1985.

A relational data base machine: First step to knowledge base machine

The Japans Fifth Generation Computer System project is divided into three stages. In the first three-year stage, a working relational data base machine is developed for a software development support system to be used in the second stage and also for an experimental system which provides a research tool for the knowledge base machine. The paper briefly describes the concepts and architecture of the relational data base machine named “Delta” which is currently under development at ICOT.

A Superimposed Code Scheme for Deductive Databases

An experimental distributed knowledge base system, KBMS PHI, is being developed as a part of the knowledge base research in the Fifth Generation Computer Systems project. A query expressed in Horn clause form is combined with related rules and compiled to relational operations to realize efficient processing in PHI.

Selection propagation in deductive databases

Abstract This paper discusses the relationship between two optimization methods in deductive databases: the distribution of selections and the magic sets method. The former is a direct generalization of pushing selections in relational databases, and the latter realizes a more general view of selection propagation. The characteristics of the generalized form of the distribution of selections are discussed and compared to other methods. It is shown that the distribution of selections corresponds to one of the least effective variations of the magic sets method. It is also shown that both methods have essentially the same power for non-recursive queries. Hence, the magic sets method can be regarded as a natural generalization of pushing selections in relational databases.

An overall network architecture suitable for implementation with either datagram or virtual circuits facilities

Computer networks were mainly developed for use by universities and research institutes, as is apparent in the case of the ARPA network. In recent years, however, general demand by other users for computer network capabilities has been rapidly expanding. One reason for this growing demand is that diffused data communication systems call for more highly sophisticated techniques. Another reason is the tendency toward decentralized processing to solve various problems experienced in large-scale centralized systems.

Distribution of Selections: The Missing Link between Strategies for Relational Databases and Deductive Databases

This paper discusses the relationship between the distribution of selections (DS) and other methods for query processing in deductive databases. A method that distributes selections for general recursive queries is proposed. It is shown that there is a guarantee that QSQ and the magic set (MS) are at least as effective as DS as far as the selection propagation is concerned. It is also shown that DS precisely corresponds to a weak variation of MS, and that MS is as effective as DS for non-recursive queries. Hence, MS can be regarded as natural generalizations of the selection-first principle in relational databases.