SPARQL

Making charts out of SPARQL query results with sgvizler

Embed a query in your HTML, name an endpoint, and pick a chart type.

I finally got around to trying sgvizler, and I wish I’d done so earlier. Once your HTML page references the sgvizler JavaScript and CSS, you can specify a query to send to any SPARQL endpoint you want and then see a chart of the query results on that web page. Scroll down a bit on sgvizler’s Google code home page and you’ll see a nice range of available chart types.

Using VALUES to map values in a SPARQL query

The VALUES keyword: even better than I thought.

Note: Ebook versions of the “raw, unedited” version of the new expanded edition of my book Learning SPARQL are now available on O’Reilly’s website, and the cooked, edited version (not much different, really) should be available in all formats within a few days. While this edition adds coverage of the VALUES keyword, I came up with the example below too late to include it.)

When I first heard about the SPARQL endpoint for the Europeana aggregation of data about European cultural artifacts, the first example I heard about was an MP3 audio file of a Slovenian version of O sole mio. I happened to be in the middle of packing for a family visit over Christmas and immediately tweeted “Lots of holiday stuff to do, but the new Ontotext Europeana SPARQL endpoint points to MP3s! So tempting…” This past Sunday morning I finally made some time to explore it…