Views and Updates over Distributed Databases
(Extended Abstract)

J.A. Makowsky and E. Ravve

{June 1998}
With the frequent use of the Internet it becomes customary to have databases distributed over many sites without that the user has to know the exact physical location of the database. What a user will see is one (virtual) database instance over a fixed database scheme. Queries and updates are submitted to a central processing site which will compute the required view or transaction by distributing the appropriate subtasks to the different sites. In this paper we offer a method which computes from the syntactic form of a query and from the structure of the connections between the sites a sequence of queries which can be computed locally at each site, and an algorithm which pieces these local queries together to the global answer. The same method can also be used for the incremental view maintenance under updates.