Local Propagation in Bayesian Networks Versus Semi-Join Program in Databases

In this paper, we study the local propagation method used in Bayesian net for belief updating from a relational database perspective. We point out and prove that the renowned local propagation method is in fact a (generalized) semi-join program used in relational database for answering database queries. This interesting connection implies and suggests that the task of belief updating can be reconsidered as a database query problem.