A Constraint Satisfaction based Approach to View Selection in a Distributed Context
نویسندگان
چکیده
Les vues matérialisées sont utilisées dans les systèmes de gestion de bases de données commercialisés pour accélérer le temps de traitement des requêtes. Cette technique est aussi très utile dans les entrepôts de données pour améliorer les performances des requêtes décisionnelles. Cependant, le problème de sélection de vues a été étudié surtout dans un contexte centralisé. Dans cet article, nous abordons le problème de sélection de vues dans un environnement distribué. Pour ce faire, nous avons étendu le concept des graphes de vues AND-OR qui permet de capturer les caractéristiques d'un système distribué. Nous proposons ensuite une méthode utilisant la programmation par contraintes pour la modélisation et la résolution du problème de sélection de vues sous des contraintes de ressources multiples. Nous montrons expérimentalement que notre approche fournit de meilleures performances au sens où elle permet d'améliorer la qualité des solutions en réduisant davantage encore le coût de traitement des requêtes.
منابع مشابه
A Declarative Approach to Modeling and Solving the View Selection Problem. (Une approche déclarative pour la modélisation et la résolution du problème de la sélection de vues à matérialiser)
View selection is important in many data-intensive systems e.g., commercial database and data warehousing systems to improve query performance. View selection can be de ned as the process of selecting a set of views to be materialized in order to optimize query evaluation. To support this process, di erent related issues have to be considered. Whenever a data source is changed, the materialized...
متن کاملThe effectiveness of couple therapy based on reality therapy approach based on selection theory on marital satisfaction of military couples
Introduction: Family is the first context in which people think, feel and behave, learn and grow. Lack of marital satisfaction or increased marital conflict can lead to phenomena such as divorce, which causes the collapse of the most fundamental part of society, the family. The aim of this study was to investigate the effectiveness of couple therapy based on the theory-based reality therapy app...
متن کاملView Selection under Multiple Resource Constraints in a Distributed Context
The use of materialized views in commercial database systems and data warehousing systems is a common technique to improve the query performance. In past research, the view selection issue has essentially been investigated in the centralized context. In this paper, we address the view selection problem in a distributed scenario. We rst extend the AND-OR view graph to capture the distributed fea...
متن کاملA Declarative Approach to View Selection Modeling
View selection is important in many data-intensive systems e.g., commercial database and data warehousing systems. Given a database (or a data warehouse) schema and a query workload, view selection is to choose an appropriate set of views to be materialized that optimizes the total query cost, given a limited amount of resource, e.g., storage space and total view maintenance cost. The view sele...
متن کاملPrivacité dans les DisCSP pour agents utilitaires
Privacy has traditionally been a major motivation for distributed problem solving, and particularly for Distributed CSP (DisCSP). However, even though several metrics have been proposed to quantify it, none of them is widely used. In this paper, we approach the problem by assuming that computation is performed among utility-based agents. In this context, we introduce a DisCSP model based on the...
متن کامل