Want to keep learning?

This content is taken from the University of Southampton's online course, Introduction to Linked Data and the Semantic Web. Join the course to learn more.

Assigning variables

If you want to construct RDF triples using a variable that is derived from retrieved data, e.g., through an arithmetical operation, you can add a BIND statement to the WHERE clause as follows:

PREFIX dbpedia: <http://dbpedia.org/resource/>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX mo: <http://purl.org/ontology/mo/>

CONSTRUCT { ?track mo:runtime ?secs } 
WHERE { dbpedia:The_Beatles foaf:made ?album .
    ?album mo:record ?record .
    ?record mo:track ?track .
    ?track mo:duration ?duration .
    BIND ((?duration/1000) AS ?secs) .

In this way the object of mo:runtime will be given in seconds rather than milliseconds.

This work is a derivative of ‘Using Linked Data Effectively’ by The Open University (2014) and licensed under CC by 4.0 International Licence adapted and used by the University of Southampton. http://www.euclid-project.eu/

Share this article:

This article is from the free online course:

Introduction to Linked Data and the Semantic Web

University of Southampton

Get a taste of this course

Find out what this course is like by previewing some of the course steps before you join: