Efficient recursive aggregation and negation in deductive databases

We present an efficient evaluation technique for modularly stratified deductive database programs for which the local strata level mappings are known at compile time. We present an important subclass of these programs (called EMS-programs) in which one can easily express problems, such as shortest distance, company ownership, bill of materials, and preferential vote counting. Programs written in this style have an easy-to-understand semantics and can be efficiently computed. Another important virtue of these programs is that their modular-stratification properties are independent of the extensional database.