In this paper we present a new approach that handles query containment problems by expressing them as a view updating problem. Since this approach is independent of any particular view updating method, it provides a general framework that joins research efforts in both the query containment checking and view updating fields. In particular, the larger development of current view updating technol...

The well-developed traditional data management techniques need to be augmented with new approaches in order to continue to be effective in the mobile environment. In this paper, we focus on the challenge of maintaining integrity constraints in the presence of disconnections and expensive communication. Our approach of localization is to reformulate global constraints so as to enhance the autono...

In this paper, a series of knowledge fusion operators are motivated and analyzed. They are defined in a semantic way, although syntactical facets of knowledge are taken into account. More precisely, they rely on a rank-ordering of interpretations that is based on the number of formulas that the interpretations falsify. It is briefly discussed how these operators could be refined, by talung into...

Integrity maintenance methods have been defined for preventing updates from violating integrity constraints. Depending on the update, the full check for constraint satisfaction is reduced to checking certain instances of some relevant constraints only. In the first part of the paper new ideas are proposed for enhancing the efficiency of such a method. The second part is devoted to checking cons...

When two or more databases are combined into a global one, integrity may be violated even when each database is consistent with its own local integrity constraints. Efficient methods for checking global integrity in data integration systems are called for: answers to queries can then be trusted, because either the global database is known to be consistent or suitable actions have been taken to ...