Which enforces that, in case of conflicts between rules, more recent rules are preferred and older rules are overridden.
Published in Chapter:
A Roadmap on Updates
Fernando Zacarías Flores (Benemérita Universidad Autónoma de Puebla, Mexico), Dionicio Zacarías Flores (Benemérita Universidad Autónoma de Puebla, Mexico), Rosalba Cuapa Canto (Benemérita Universidad Autónoma de Puebla, Mexico), and Luis Miguel Guzmán Muñoz (Benemérita Universidad Autónoma de Puebla, Mexico)
Copyright: © 2009
|Pages: 6
DOI: 10.4018/978-1-59904-849-9.ch201
Abstract
Updates, is a central issue in relational databases and knowledge databases. In the last years, it has been well studied in the non-monotonic reasoning paradigm. Several semantics for logic program updates have been proposed (Brewka, Dix, & Knonolige 1997), (De Schreye, Hermenegildo, & Pereira, 1999) (Katsumo & Mendelzon, 1991). However, recently a set of proposals has been characterized to propose mechanisms of updates based on logic and logic programming. All these mechanisms are built on semantics based on structural properties (Eiter, Fink, Sabattini & Thompits, 2000) (Leite, 2002) (Banti, Alferes & Brogi, 2003) (Zacarias, 2005). Furthermore, all these semantic ones coincide in considering the AGM proposal as the standard model in the update theory, for their wealth in properties. The AGM approach, introduced in (Alchourron, Gardenfors & Makinson, 1985) is the dominating paradigm in the area, but in the context of monotonic logic. All these proposals analyze and reinterpret the AGM postulates under the Answer Set Programming (ASP) such as (Eiter, Fink, Sabattini & Thompits, 2000). However, the majority of the adapted AGM and update postulates are violated by update programs, as shown in (De Schreye, Hermenegildo, & Pereira, 1999).