Given a universe U of n elements and a weighted collection S of m subsets of U, the universal set cover problem is to a-priori map each element u ∈ U to a set S(u) ∈ S contain...
In a simple cooperative MAS model where a collection of "querying agents" can send queries to a collection of "information agents", we formalize the problem of ...
Temporal aggregate queries retrieve summarized information about records with time-evolving attributes. Existing approaches have at least one of the following shortcomings: (i) th...
In database query processing, actual run-time conditions (e.g., actual selectivities and actual available memory) very often differ from compile-time expectations of run-time cond...
Query optimizers normally compile queries into one optimal plan by assuming complete knowledge of all cost parameters such asselectivity and resourceavailability. The execution of...