Update Propagation in Deductive Databases Using Soft Stratification

Update propagation in deductive databases can be implemented by combining rule rewriting and fixpoint computation, analogous to the way how query answering is performed via Magic Sets. For efficiency reasons, bottom-up propagation rules have to be subject to Magic rewriting, thus possibly loosing stratifiability. We propose to use the soft stratification approach for computing the well-founded model of the magic propagation rules (guaranteed to be two-valued) because of the simplicity and efficiency of this technique.