We present an optimization method and algorithm designed for three objectives: physical data independence, semantic optimization, and generalized tableau minimization. The method ...
Abstract. In emerging data stream applications, data sources are typically distributed. Evaluating multi-join queries over streams from different sources may incur large communica...
We present an improved oracle for the distance sensitivity problem. The goal is to preprocess a directed graph G = (V, E) with non-negative edge weights to answer queries of the f...
A tuple t1 of relation R subsumes tuple t2 of R, with respect to a query Q if for every database, tuple t1 derives all, and possibly more, answers to query Q than derived by tuple ...
Severalmethodshavebeenproposedto compile recursive Datalog programs. The most well-known perform a rewriting of rules using MAGIC or PROBLEM predicates in order to push selections...