Abstract: A system, computer-implemented method, and computer-program product embodiments for determining a cardinality estimate for a query. A cardinality estimator identifies a predicate in a query, where the predicate is split into a plurality of equivalence classes. The cardinality estimator then generates a plurality of equivalence graphs from the plurality of equivalence classes, one equivalence graph for an equivalence class. Spanning trees are identified from the plurality of equivalence graphs, and the cardinality estimator then determines the cardinality estimate for the query from the spanning trees.