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Efficient consistency maintenance of incomplete and dynamic real-life databases is a quality label for further data analysis. In prior work, we tackled the generic problem of database updating in the presence of tuple generating constraints from a theoretical viewpoint. The current paper considers the usability of our approach by (a) introducing incremental update routines (instead of the previous from-scratch versions) and (b) removing the restriction that limits the contents of the database to fit in the main memory. In doing so, this paper offers new algorithms, proposes queries and data models inviting discussions on the representation of incompleteness on databases. We also propose implementations under a graph database model and the traditional relational database model. Our experiments show that computation times are similar globally but point to discrepancies in some steps.

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As the Linked Open Data and the number of semantic web data providers hugely increase, so does the critical importance of the following question: how to get usable results, in particular for data mining and data analysis tasks? We propose a query framework equiped with integrity constraints that the user wants to be verified on the results coming from semantic web data providers. We precise the syntax and semantics of those user quality constraints. We give algorithms for their dynamic verification during the query computation, we evaluate their performance with experimental results, and discuss related works.

This paper introduces SetUp, a theoretical and applied framework for the management of RDF/S database evolution on the basis of graph rewriting rules. Rewriting rules formalize instance or schema changes, ensuring graph's consistency with respect to given constraints. Constraints considered in this paper are a well known variant of RDF/S semantic, but the approach can be adapted to user-defined constraints. Furthermore, SetUp manages updates by ensuring rule applicability through the generation of side-effects: new updates which guarantee that rule application conditions hold. We provide herein formal validation and experimental evaluation of SetUp. CCS CONCEPTS• Information systems → Graph-based database models; • Theory of computation → Rewrite systems.