Secure Data Provenance and Inference Control with Semantic Web

A Language for Provenance Access Control ◾ 129

3. If P is a graph pattern and R is a built-in SPARQL condition, then the expres-

sion (P FILTER R) is a graph pattern

4. If P is a graph pattern, V is a set of variables and X ∈

U

∪ V, then (X GRAPH

P) is a graph pattern

e current W3C recommendation for SPARQL does not support paths of

arbitrary length; therefore, extensions are needed to answer the queries over the

provenance graph (Detwiler et al. 2008). Many approaches to supporting paths of

arbitrary length have been proposed in the literature, which include Alkhateeb et

al. (2009), Detwiler et al. (2008), and Koch et al. (2005). A W3C recommenda-

tion extending SPARQL to support property paths can be found in Harris and

Seaborne (2010)