Query optimization in compressed database systems

Join Query Optimization in Parallel Database Systems

In this paper we present a new framework for studying parallel query optimization. We first note that scheduling and optimization must go together in a parallel environment. We introduce the concept of response time envelopes which integrates scheduling and optimization. We show that it can be used effectively to develop parallel query optimization algorithms which have same order of complexity...

Query Optimization in Distributed Database Systems

The query optimizer is widely considered to be the most important component of a database management system. It is responsible for taking a user query and searching through the entire space of equivalent execution plans for a given user query and returning the execution plan with the lowest cost. This plan can then be passed to the executer, which can carry out the query. Plans can vary signifi...

Algebraic query optimization in database systems

Decoupled Query Optimization for Federated Database Systems

We study the problem of query optimization in federated database systems. The nature of federated databases explicitly decouples many aspects of the optimization process, often making it imperative for the optimizer to consult underlying data sources while doing cost-based optimization. This not only increases the cost of optimization, but also changes the trade-offs involved in the optimizatio...

Query Optimization in Database Grid

DarGridII is an implemented database gird system whose goal is to provide a semantic solution for integrating database resources on the web. Although many algorithms have been proposed for optimizing query-processing in order to minimize costs and/or response time, associated with obtaining the answer to query in a distributed database system, database grid query optimization problem is fundame...