Computing the skyline of a relational table based on a query lattice.

We propose a novel approach to computing the skyline set of a relational table R, with respect to preferences expressed over one or more numerical attributes. Our approach is based on what we call the query lattice of R, and our basic algorithm constructs the skyline set as the union of the answers to a subset of queries from that lattice - hence without directly accessing the table R. Therefore, in contrast to all existing techniques, our approach is independent of how the table R is implemented or how its tuples are indexed. We demonstrate the general- ity of our approach by computing the skyline set of the join of two tables based on the product of their individual query lattices - therefore without performing the join. The paper presents basic concepts and algorithms leaving experimentation and performance evaluation to a forthcoming paper.