Querying Description Logic knowledge bases has received great attention in the last years. In such a problem, the need of coping with incomplete information is the distinguishing feature with respect to querying databases. Due to this feature, we have to deal with two conflicting needs: on the one hand, we would like to query the knowledge base with sophisticated mechanisms provided by full first-order logic (FOL); on the other hand, the presence of incomplete information makes query answering a much more difficult task than in databases. In this paper we advocate the use of a nonmonotonic epistemic FOL query language as a means for expressing sophisticated queries over Description Logic knowledge bases. We show that through a controlled use of the epistemic operator, resulting in the language called EQL-Lite, we are able to formulate full FOL queries over Description Logic knowledge bases, while keeping computational complexity of query answering under control. In particular, we show that EQL-Lite queries over DL-Lite knowledge bases are FOL reducible (i.e., compilable into SQL) and hence can be answered in LOGSPACE through standard database technologies.

EQL-Lite: Effective first-order query processing in Description Logics / Calvanese, D; DE GIACOMO, Giuseppe; Lembo, Domenico; Lenzerini, Maurizio; Rosati, Riccardo. - (2007), pp. 274-279. (Intervento presentato al convegno 20th International Joint Conference on Artificial Intelligence, IJCAI 2007 tenutosi a Hyderabad; India nel Gennaio 2007).

EQL-Lite: Effective first-order query processing in Description Logics

DE GIACOMO, Giuseppe;LEMBO, Domenico;LENZERINI, Maurizio;ROSATI, Riccardo
2007

Abstract

Querying Description Logic knowledge bases has received great attention in the last years. In such a problem, the need of coping with incomplete information is the distinguishing feature with respect to querying databases. Due to this feature, we have to deal with two conflicting needs: on the one hand, we would like to query the knowledge base with sophisticated mechanisms provided by full first-order logic (FOL); on the other hand, the presence of incomplete information makes query answering a much more difficult task than in databases. In this paper we advocate the use of a nonmonotonic epistemic FOL query language as a means for expressing sophisticated queries over Description Logic knowledge bases. We show that through a controlled use of the epistemic operator, resulting in the language called EQL-Lite, we are able to formulate full FOL queries over Description Logic knowledge bases, while keeping computational complexity of query answering under control. In particular, we show that EQL-Lite queries over DL-Lite knowledge bases are FOL reducible (i.e., compilable into SQL) and hence can be answered in LOGSPACE through standard database technologies.
2007
20th International Joint Conference on Artificial Intelligence, IJCAI 2007
Database technology; Description logic; First order logic
04 Pubblicazione in atti di convegno::04b Atto di convegno in volume
EQL-Lite: Effective first-order query processing in Description Logics / Calvanese, D; DE GIACOMO, Giuseppe; Lembo, Domenico; Lenzerini, Maurizio; Rosati, Riccardo. - (2007), pp. 274-279. (Intervento presentato al convegno 20th International Joint Conference on Artificial Intelligence, IJCAI 2007 tenutosi a Hyderabad; India nel Gennaio 2007).
File allegati a questo prodotto
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/233544
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 111
  • ???jsp.display-item.citation.isi??? 42
social impact