A Framework for Creating Global Schema Using Proxy Tables from Distributed Heterogeneous Relational Databases in Multidatabase System
Mohammad Ghulam Ali · International Journal of Computer and Electrical Engineering · 2010
Creating a proxy table, this is an alternative way of looking at the data in one or more tables from different geographical located local component heterogeneous relational databases.Proxy tables provide indirect access to the data in remote tables.Location transparency of remote data will be maintained by creating a proxy table.The proxy table will be mapped with the remote table and view.The schema for proxy table resides in the multidatabase system but data resides in the remote locations.In this paper, we propose a framework to construct a Global Schema with a set of proxy tables created from different remote local databases.We can further merge two or more proxy tables to get results from two or more remote tables located in different sites.We have also illustrated the method of creating Global Schema with an example.Query submitted on proxy table without join, union or intersect will straightway go to the respective remote table or view and will send back results to the concerned user.Query submitted using join, union or intersect on two or more proxy tables will be decomposed into a set of sub queries and will go similarly to respective remote tables or views and individual sub-query will be executed at each remote sites and finally all sub-queries will be composed and will get back results to the concerned user.