Section: New Results

Query processing for the Web

Query languages for graph databases. Graph-structured data on the Web can be found in emerging applications such as RDF and linked data, or social networks. Classical database languages are not suitable to query such data, essentially because they do not allow to (easily) express simple connectivity queries, which are the basic building block in graph navigation. We use Regular Path Queries, computing pairs of nodes reachable via a path satisfying a regular expression. We have tackled the problem of answering queries over graph databases which are available only trough a given set of views. We have shown that in the “asymptotic case”, i.e. when the query is large enough relative to the view definition, it is decidable whether the view determines the query [22] .