Abstract—Linked Open Data (LOD) is a principle to publish
machine readable data on the Web, and has been gaining growing
attention owing to the recent upsurge of open data movement.
For this reason, there are strong demands to develop applications
that utilize LOD. To develop such an application, developers need
to use SPARQL, a query language for RDF data, to access LOD,
but there are several barriers: 1) to write an appropriate query,
one needs to know the precise graph structure of RDF data
being queried, although the graph structure of LOD datasets is
in many cases very complicated and therefore hard to learn; and
2) it is hard for many users to learn SPARQL. To cope with this
problem, in this paper, we propose a system for users to be able to
query RDF data without learning SPARQL. Instead, we introduce
JSON-style view on top of SPARQL endpoints. Having defined
JSON-style views, ordinary users can issue queries against the
views using LINQ, a structured query language similar to SQL.
The system translates LINQ queries to corresponding SPARQL
queries according to the view definition, and send the translated
query to the SPARQL endpoint. The resulting data returned by
SPARQL endpoints are processed and returned back to the user.
We conduct experiments to show the feasibility of the proposed
system.