Towards a new approach for an effective querying of distributed databases

Abstract

Nowadays, with the evolution of data and their geographical distribution, Distributed Database Management Systems (DDBMS) have become undoubtedly a need for Information Systems (IS) users. Unfortunately, query optimization remains a handicap for existing DDBMS, given the high cost of network traffic caused by the access to geographically distributed data in different sites. To remedy this problem, we propose a new effective approach of querying Distributed Database (DDB) based on the definition of relevant sites to the query knowing fragmentation and/or duplication of distributed data. This approach allows us to minimize the volume of transferred data via network and consequently reduces the query execution cost. This approach has been validated by implementing a layer “effective-query” on Oracle DDBMS.