2 citations · 2 across the 6 of their papers we have counts for
10 papers
Someone slept in my bed! On the entailment problem for conjunctive queries with safe negation over DL-Lite knowledge bases
Jerzy Marcinkowski, Piotr Ostropolski-Nalewaja
We solve a long standing open problem, showing that the query answering for conjunctive queries with safe negation, over DL-Lite knowledge bases, is undecidable.
On the entailment problem for DL-Lite ontologies and conjunctive queries with negation
Jerzy Marcinkowski, Piotr Ostropolski-Nalewaja
We show that the entailment problem, for a given entailment problem for DL-Lite ontology, and given conjunctive query with inequalities, is undecidable. We also show that…
About the Multi-Head Linear Restricted Chase Termination
Lukas Gerlach, Lucas Larroque, Jerzy Marcinkowski +1
The chase is a ubiquitous algorithm in database theory. However, for existential rules (aka tuple-generating dependencies), its termination is not guaranteed, and even undecidable…
Bag Semantics Query Containment: The CQ vs. UCQ Case and Other Stories
Jerzy Marcinkowski, Piotr Ostropolski-Nalewaja
Query Containment Problem (QCP) is a fundamental decision problem in query processing and optimization. While QCP has for a long time been completely understood for the case of set…
Monotone Rewritability and the Analysis of Queries, Views, and Rules
Michael Benedikt, Stanislav Kikot, Johannes Marti +1
We study the interaction of views, queries, and background knowledge in the form of existential rules. The motivating questions concern monotonic determinacy of a query using views…
Determinacy of Real Conjunctive Queries. The Boolean Case
Jarosław Kwiecień, Jerzy Marcinkowski, Piotr Ostropolski-Nalewaja
In their classical 1993 paper [CV93] Chaudhuri and Vardi notice that some fundamental database theory results and techniques fail to survive when we try to see query answers as bag…