The alternating fixpoint of logic programs with negation
PODS '89 Proceedings of the eighth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Consistent query answers in inconsistent databases
PODS '99 Proceedings of the eighteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Preferred answer sets for extended logic programs
Artificial Intelligence
Prioritized logic programming and its application to commonsense reasoning
Artificial Intelligence
Data integration: a theoretical perspective
Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
On the Problem of Computing the Well-Founded Semantics
CL '00 Proceedings of the First International Conference on Computational Logic
On the decidability and complexity of query answering over inconsistent and incomplete databases
Proceedings of the twenty-second ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
A Logical Framework for Querying and Repairing Inconsistent Databases
IEEE Transactions on Knowledge and Data Engineering
Efficient query reformulation in peer data management systems
SIGMOD '04 Proceedings of the 2004 ACM SIGMOD international conference on Management of data
Logical foundations of peer-to-peer data integration
PODS '04 Proceedings of the twenty-third ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Integrating and Querying P2P Deductive Databases
IDEAS '06 Proceedings of the 10th International Database Engineering and Applications Symposium
Composing mappings among data sources
VLDB '03 Proceedings of the 29th international conference on Very large data bases - Volume 29
Queries and updates in the coDB peer to peer database system
VLDB '04 Proceedings of the Thirtieth international conference on Very large data bases - Volume 30
IJCAI'03 Proceedings of the 18th international joint conference on Artificial intelligence
Inconsistency tolerance in P2P data integration: an epistemic logic approach
DBPL'05 Proceedings of the 10th international conference on Database Programming Languages
Query answering in peer-to-peer data exchange systems
EDBT'04 Proceedings of the 2004 international conference on Current Trends in Database Technology
Aggregates and priorities in P2P data management systems
Proceedings of the 15th Symposium on International Database Engineering & Applications
Handling preferences in p2p systems
FoIKS'12 Proceedings of the 7th international conference on Foundations of Information and Knowledge Systems
Restoring consistency in p2p deductive databases
SUM'12 Proceedings of the 6th international conference on Scalable Uncertainty Management
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Data Integration in Peer-to-Peer(P2P) systems is concerned with the ability of physically connect autonomous sources (peer) for sharing and reuse information and for the creation of new information from existing one. In a P2P system a query can be posed to any peer and the answer is provided by integrating locally stored data with data provided from its neighbors. Anyhow, while collecting data for answering queries, imported data may corrupt the local database due to the violation of some integrity constraint, therefore inconsistencies have to be managed. This paper contributes to the proposal of a logic based framework for data integration and query answering in a Peer-to-Peerenvironment. It is based on [11,12] in which the Preferred Weak Model Semantics, capturing a different perspective for P2P data integration, has been proposed: just data not violating integrity constraints are exchanged among peers by using mapping rules. The motivation of this work stems from the observation that the complexity of computing preferred weak models in [11,12] does not let the approach to be implemented in practical applications. Therefore, a more pragmatic solution seems to be desirable for assigning semantics to a P2P system. First, the paper proposes a rewriting technique that allows modeling a P2P system, ${\mathcal {PS}}$, as a unique logic program, Rewt(${\mathcal {PS}}$), whose stable models correspond to the preferred weak models of ${\mathcal {PS}}$. Then, it presents the Well Founded Model Semantics, that allows obtaining a deterministic model whose computation is polynomial time. This is a (partial) stable model obtained by evaluating with a three-value semantics a logic program obtained from Rewt(${\mathcal {PS}})$. Finally, the paper provides results on the complexity of answering queries in a P2P system.