Abstract. Social Network (SN) data has become ubiquitous, demanding advanced and flexible means to represent, transform and query such data. In addition to the intrinsic challenge...
Probabilistic processes appear naturally in various contexts, with applications to Business Processes, XML data management and more. Many models for specifying and querying such p...
Experience with relational systems has shown that distribution is an effective way of improving the scalability of query evaluation. In this paper, we show how distributed query e...
Understanding how users tailor their SPARQL queries is crucial when designing query evaluation engines or fine-tuning RDF stores with performance in mind. In this paper we analyz...
Probabilistic databases hold promise of being a viable means for large-scale uncertainty management, increasingly needed in a number of real world applications domains. However, q...
There has been a recent surge in work in probabilistic databases, propelled in large part by the huge increase in noisy data sources -from sensor data, experimental data, data fro...
Our experimental analysis of several popular XPath processors reveals a striking fact: Query evaluation in each of the systems requires time exponential in the size of queries in ...
Hypothetical queries are queries embedding hypotheses about the database. The embedded hypothesis in a hypothetical query indicates, so to say, a state of the database intended for...
Abstract— This paper presents our work on supporting flexible query evaluation over large distributed, heterogeneous, and autonomous sources. Flexibility means that the query ev...
The paper proposes an approach to information retrieval based on the use of a structure (ontology) both for document (resp. query) indexing and query evaluating. The conceptual st...