In a recent paper by Hellerstein [15], a tight relationship was conjectured between the number of strata of a Datalog¬ program and the number of “coordination stages” require...
The problems of query containment, equivalence, and minimization are recognized as very important in the context of query processing, specifically of query optimization. In their...
A universal model of a database D and a set Σ of integrity constraints is a database that extends D, satisfies Σ, and is most general in the sense that it contains sound and co...
Abstract. Lateral gene transfer (LGT) is a common mechanism of nonvertical evolution where genetic material is transferred between two more or less distantly related organisms. It ...
Background: Paralog reduction, the loss of duplicate genes after whole genome duplication (WGD) is a pervasive process. Whether this loss proceeds gene by gene or through deletion...