Hybrid query plan generation

A hybrid query is a requirement of data produced by data services and a set of QoS preferences w.r.t. the query execution. In this paper we present the problem of the hybrid query optimization and, in particular, the generation of a search space of hybrid query plans. We show how the constraints for generating hybrid query plans are modeled and validate these constraints by implementing them in an action language. We present graphs with experiment results that show the complexity of this generation.