Different ways of distributing relational data are described and studied according to the manipulation operators: get, insert, delete, update tuples. In a distributed DBMS, distributed relations are split into fragmen...
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Different ways of distributing relational data are described and studied according to the manipulation operators: get, insert, delete, update tuples. In a distributed DBMS, distributed relations are split into fragments which are spread over several computers, but the user sees them as if they were in a centralized database. When a manipulation operation takes place on a distributed relation, it has to be propagated onto the underlying fragments. We propose a formalism to express this propagation. This formalism not only expresses what operations have to be performed but how these operations can be performed, i. e. in sequence and/or parallel.
In distributed object-oriented databases (DOODB), objects is distributed in different sites on communication networks. In DOODB, class fragmentation to divide a class into fragments is needed for improving performance...
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ISBN:
(纸本)0818682272
In distributed object-oriented databases (DOODB), objects is distributed in different sites on communication networks. In DOODB, class fragmentation to divide a class into fragments is needed for improving performance and for reducing data transfer, Class fragmentation is different from conventional relational databases, We have proposed the vertical class fragmentation to reflect the characteristics of object-oriented databases. In this paper we define the attribute partitioning algorithm and describe the results of implementation and comparison.
A prototype of an object-oriented system implemented in C_Prolog is described. Its main objective is to demonstrate system features that would support efficient management of objects and object-oriented databases in a...
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ISBN:
(纸本)0818620528
A prototype of an object-oriented system implemented in C_Prolog is described. Its main objective is to demonstrate system features that would support efficient management of objects and object-oriented databases in a persistent and distributed environment. Mechanisms at the low level of the system were considered to support object distribution, mobility control, and configuration management in a simple and uniform way. Objects exist in clusters, which are transparent to the applications. The prototype is a framework for a self-organizing object-oriented distributed system.
Integrity constraint handling is considered an important issue in relational database management systems. Many studies were already conducted in this area. Little attention has been paid however to the influence of re...
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ISBN:
(纸本)0818620528
Integrity constraint handling is considered an important issue in relational database management systems. Many studies were already conducted in this area. Little attention has been paid however to the influence of relation fragmentation and parallelism on constraint handling. This paper shows how relation fragmentation complicates matters on the one hand, but how parallelism can help to get better efficiency in enforcing constraints on the other hand. The ideas as presented in this paper are used in the context of the PRISMA database machine; they have a more general applicability though.
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