2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/121692We show that for every conjunctive query, the complexity of evaluating it on a probabilistic database is either \PTIME or #¶-complete, and we give an algorithm for deciding whether a given conjunctive query is \PTIME or #¶-complete. The dichotomy property is a fundamental result on query evaluation on probabilistic databases and it gives a complete classification of the complexity of conjunctive queries.Databasestext