SPARQL

by Qiu Ji

To query an ontology.

Versions & Compatibility

This section shows available versions of SPARQL and for each version its compatible application versions and necessary plugins.

Changelog

Functional Description

The SPARQL Plugin allows a user to do conjunctive queries. It receives an OWL ontology and a query expressed using SPARQL syntax as inputs and outputs the answers in a table. This reasoning task is performed using the inference engine in KAON2.

Installation and Update

The plugin can be installed and updated via NeOn-Toolkit Update Site:

• Within the NeOn-Toolkit open the Help-menu and select the entry Software Updates->Find and Install ....
• Select Search for new features to install in the appearing window and click Next.
• Then choose the NeOn-Toolkit Update Site and click Finish.
• In the appearing window you can find the SPARQL plugin under the reasoning category. Select the feature of SPARQL and then click Next and follow the installation instructions shown by the toolkit.

User Documentation

• 1. Open the view of "SPARQL Query": In the menu of "Windows", please choose Show view / Other / SPARQL Query.
• 2. How to use it: First of all, choose a project and an ontology in the project. The default namespace of this ontology will be shown automatically. Then the user can input a SPARQL query in the text area. Take the following as an example:

PREFIX wine: <http://www.w3.org/TR/2003/PR-owl-guide-20031209/wine#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
SELECT ?x WHERE { ?x wine:hasFlavor wine:Strong .  ?x wine:locatedIn wine:NewZealandRegion .  ?x wine:hasSugar wine:Dry }

After pressing "Execute Query", the result of the query will be shown in the table if the syntax of the input query is correct. Otherwise, a warning dialog will be shown to the user. Finally, the user could save the query results to a local file.

Category: Plugin