Abstract: Techniques are disclosed for generating conditional functional dependency (CFD) pattern tableaux having the desirable properties of support, confidence and parsimony. These techniques include both a greedy algorithm for generating a tableau and, for large data sets, an “on-demand” algorithm that outperforms the basic greedy algorithm in running time by an order of magnitude. In addition, a range tableau, as a generalization of a pattern tableau, can achieve even more parsimony.

Abstract: A method and system are disclosed for operating a high speed data stream management system which runs a query plan including a set of queries on a data feed in the form of a stream of tuples. A predicate prefilter is placed outside the query plan upstream of the set of queries, and includes predicates selected from those used by the queries. Predicates are selected for inclusion in the prefilter based on a cost heuristic, and predicates are combined into composites using a rectangle mapping heuristic. The prefilter evaluates the presence of individual and composite predicates in the tuples and returns a bit vector for each tuple with bits representing the presence or absence of predicates in the tuple. A bit signature is assigned to each query to represent the predicates related to that query, and a query is invoked when the tuple bit vector and the query bit signature are compatible.