Pulls data from a different SPARQL endpoints in one single query using the SERVICE directive. – Linked Data for Professional Education

Visualising The Location Graph With Gephi and Ordnance Survey Linked Data

Sat, 14 Jan 2017 06:46:01 +0000

Building on a previous post, the author shares another example using a SPARQL endpoint to query Linked Open Data and turn the results into a graph (aka, "network") visualization using the Gephi tool (and its 'Semantic Web Import' plugin). Includes an example of federated search as well as a work-around to convert SPARQL results from Turtle to XML.

URL: https://johngoodwin225.wordpress.com/2014/03/28/visualising-the-location-graph-example-with-gephi-and-ordnance-survey-linked-data/
Keywords: Gephi, DBpedia, Geospatial data, SPARQL
Author: Goodwin, John
Date created: 2014-03-26 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M

Federating SPARQL Queries Across Government Linked Data

Thu, 29 Dec 2016 06:44:02 +0000

The author describes how to create a single SPARQL query which pulls Linked Data from two separate endpoints to answer complex questions in cases where all the necessary data cannot be found at a single source.

URL: https://johngoodwin225.wordpress.com/2014/03/22/federating-sparql-queries-across-government-linked-data/
Keywords: Government Open Data, Linked Open Data (LOD), SPARQL
Author: Goodwin, John
Date created: 2014-03-22 04:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P20M

Linked Data and SPARQL Queries Tutorial

Wed, 30 Dec 2015 18:37:26 +0000

This tutorial goes through some basic SPARQL queries in order to give the user a sense of how to discover and query different Linked Data (LD) sets. It seeks to answer, through some examples, the following questions:1. How do I know where to look to identify LD sets? 2. Once I know that a LD set of interest exists, how should I query it? 3. How do I query across different LD sets?

URL: http://ctsaconnect.org/system/files/Linked%20data%20and%20SPARQL%20queries%20tutorial.pdf
Keywords: Linked Data, Linked Open Data Cloud, Dataset, RDF, SPARQL, Query, SPARQL endpoint
Publisher: VIVO
Date created: 2012-01-01 07:00:00.000
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P30M
Educational use: instruction
Educational audience: generalPublic
Interactivity type: active

SPARQL by Example

Abi Evans — Thu, 13 Aug 2015 03:26:17 +0000

This is a very in-depth resource that covers nearly every aspect of SPARQL (both 1.0 and 1.1). Includes example queries (over many datasets), links to endpoints (ARQ, OpenLink's Virtuoso, Redland's Rasqal), and expected results. NOTE: The number of competencies tagged to this resource represent only a small portion its total coverage – it was necessary to omit many of the more commonly tagged competencies to save space.

URL: http://www.cambridgesemantics.com/semantic-university/sparql-by-example
Keywords: SPARQL, Graph traversal, Negation, SPARQL endpoint, Projected expressions
Author: Feigenbaum, Lee
Publisher: W3C SPARQL Working Group
Language: http://id.loc.gov/vocabulary/iso639-2/eng
Time required: P75M
Educational use: instruction
Educational audience: student
Interactivity type: mixed