On the Decidability of Consistent Query Answering

نویسندگان

  • Marcelo Arenas
  • Leopoldo E. Bertossi
چکیده

Consistent query answering (CQA) is about formally characterizing and computing semantically correct answers to queries posed to a database that may fail to satisfy certain integrity constraints. In this paper we revisit the decidability status of consistent query answering by considering different parameters of the problem as input to the decision problem. We obtain some new results about the undecidability and combined complexity of CQA.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Complexity of Inconsistency-Tolerant Query Answering in Datalog+/-

The study of inconsistency-tolerant semantics for query answering in ontological languages has recently gained much attention. In this work, we consider three inconsistency-tolerant semantics recently proposed in the literature, namely: consistent query answering, the intersection (also called IAR) semantics, and the intersection of closed repairs (ICR) semantics. We study the data complexity o...

متن کامل

Consistent query answering via ASP from different perspectives: Theory and practice

A data integration system provides transparent access to different data sources by suitably combining their data, and providing the user with a unified view of them, called global schema. However, source data are generally not under the control of the data integration process, thus integrated data may violate global integrity constraints even in presence of locally-consistent data sources. In t...

متن کامل

Query rewriting and answering under constraints in data integration systems

In this paper we address the problem of query answering and rewriting in global-as-view data integration systems, when key and inclusion dependencies are expressed on the global integration schema. In the case of sound views, we provide sound and complete rewriting techniques for a maximal class of constraints for which decidability holds. Then, we introduce a semantics which is able to cope wi...

متن کامل

On the Data Complexity of Consistent Query Answering over Graph Databases

Areas in which graph databases are applied – such as the semantic web, social networks and scientific databases – are prone to inconsistency, mainly due to interoperability issues. This raises the need for understanding query answering over inconsistent graph databases in a framework that is simple yet general enough to accommodate many of its applications. We follow the well-known approach of ...

متن کامل

The Two Views on Ontological Query Answering

We attempt a structured view at the ontological query answering problem by distinguishing between two antagonistic perspectives: The knowledge representation perspective considers the ontology as a part of the specified knowledge whereas the database perspective assumes it to be part of the query. These two perspectives give rise to two computation strategies: (data-driven) forward chaining and...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2010