A dichotomy for non-repeating queries with negation in probabilistic databases
Robert Fink, Dan Olteanu · 2014
This paper shows that any non-repeating conjunctive relational query with negation has either polynomial time or #P-hard data complexity on tuple-independent probabilistic databases. This result extends a dichotomy by Dalvi and Suciu for non-repeating conjunctive queries to queries with negation. The tractable queries with negation are precisely the hierarchical ones and can be recognized efficiently.