An important issue for federated systems of diverse data sources is optimizing cross-source queries, without building knowledge of individual sources into the optimizer. This pape...
Current federated systems deploy cost-based query optimization mechanisms; i.e., the optimizer selects a global query plan with the lowest cost to execute. Thus, cost functions in...
Wen-Syan Li, Vishal S. Batra, Vijayshankar Raman, ...
Today, bibliographical information is kept in a variety of digital libraries available on the Internet. The integration of bibliographical data is considered as one of the most im...
We study the problem of query optimization in federated relational database systems. The nature of federated databases explicitly decouples many aspects of the optimization proces...
: Optimizers in modern DBMSs utilize a cost model to choose an efficient query execution plan (QEP) among all possible ones for a given query. The accuracy of the cost estimates de...
Stephan Ewen, Michael Ortega-Binderberger, Volker ...