SPARQL Federated Query And Its Application On The Semantic Web

With the research and development of the semantic web and information retrieval technology, more and more RDF data appear on the Internet. Linked data can associate lots of the RDF resources. This paper studied and summarized the syntax of SPARQL1.1and studied the Linked Data and federated query based on the existing research results. Besides, we will use the extended SPARQL language to realize the federated query for the distributed data. The main work of this paper includes the following aspects:1. RDF data and Linked Data. Study the basic principles and technical system of Linked Data and how to create and publish Linked Data effectively. Besides, introduce the method of creating and publishing the Linked Data based on Cool URIs.2. SPARQL1.1query language. Introduce the basic concept of SPARQL to the SPARQL graph patterns. For the query result it can return different results by different keywords. In addition there are six ways to adjust the query results.3. The syntax and semantics of the federated query. We can use the SERVICE keyword to query the data from remote SPARQL endpoint and use OPTIONAL keyword to make the federated query between different remote SPARQL endpoints. Therefore it can realize the federated query for distributed data.4. Research and analysis for the Linked Data on "Data.Gov.UK" SPARQL endpoint. Create the application examples of the federated query to make queries between local data and remote SPARQL data, as well as making federated query between two different SPARQL endpoints.