Linked Data - Connect Distributed Data across the Web. What is Linked Data? The recent LinkedData Planet conference in NYC marked, I think, a real transition point.
The conference signaled the beginning movement of the Linked Data approach from the research lab to the enterprise. As a result, there was something of a schizophrenic aspect at many different levels to the conference: business and research perspectives; realists and idealists; straight RDF and linked data RDF; even the discussions in the exhibit area versus some of the talks presented from the podium. Like any new concept, my sense was a struggle around terminology and common language and the need to bridge different perspectives and world views.
Like all human matters, communication and dialog were at the core of the attendees’ attempts to bridge gaps and find common ground. Linked Data star scheme by example. Linked Data Marketplaces. Why Carry the Cost of Linked Data? – Tom Heath’s Displacement Activities. June 16th, 2010 by Tom Heath In his ongoing series of niggles about Linked Data, Rob McKinnon claims that “mandating RDF [for publication of government data] may be premature and costly“.
The claim is made in reference to Francis Maude’s parliamentary answer to a question from Tom Watson. How to publish Linked Data on the Web. This document provides a tutorial on how to publish Linked Data on the Web.
After a general overview of the concept of Linked Data, we describe several practical recipes for publishing information as Linked Data on the Web. This tutorial has been superseeded by the book Linked Data: Evolving the Web into a Global Data Space written by Tom Heath and Christian Bizer. This tutorial was published in 2007 and is still online for historical reasons. The Linked Data book was published in 2011 and provides a more detailed and up-to-date introduction into Linked Data. Online Access. Overview The following interfaces exist for online access: Rest Api: provides basic access to a database with a full Open Street Map (OSM) planet file loaded.
Sparql Endpoints: enable queries on databases with a reduced (but hopefully for many applications relevant) subset of the whole data loaded. The Sparql Endpoints come in two flavours: Static: Contains the data extracted from a OSM planet file of a certain date Live: Initially a copy of the static version that is then synchronized with the minutely updates from OSM. As of 2012 February 1st, the Virtuoso database powering the live SPARQL endpoint is not synchronized anymore.