Query Decompositions and All That (Invited Talk)

The close relationship between Conjunctive Queries (CQs) and Constraint Satisfaction Problems (CSPs) has long been known. Nevertheless, apart from decomposition methods, research on efficient query evaluation or constraint solving algorithms has developed rather independently. In this article, we illustrate how search algorithms originating from the CSP community can be fruitfully applied to query evaluation - either by further developing the original search algorithms or by combining them with query decomposition methods. It turns out that the resulting approaches may indeed lead to lower time and/or space complexity than previous query evaluation methods.