RDF

Reclaiming my picture metadata from flickr

Surprise: by converting multiple sources of data to triples and then running a SPARQL query.

We should give flickr some credit for providing an API that lets us download the metadata we’ve entered about our pictures (for example, titles, descriptions, and membership in custom sets such as XML Summer School 2011 or Artsier Stuff) but that metadata all refers to pictures on flickr’s servers. What if I want to use blurb.com to print a hardcopy album of one of these sets? Do I have to download that set’s pictures from flickr, even though I already have them on a hard disk,…

Simple federated queries with RDF

A few more triples to identify some relationships, and you're all set.

Once, at an XML Summer School session, I was giving a talk about semantic web technology to a group that included several presenters from other sessions. This included Henry Thompson, who I’ve known since the SGML days. He was still a bit skeptical about RDF, and said that RDF was in the same situation as XML—that if he and I stored similar information using different vocabularies, we’d still have to convert his to use the same vocabulary as mine or vice versa before we could use our…

Playing with SPARQL Graph Store HTTP Protocol

GETting, POSTing, PUTting, and DELETEing named graphs.

One of the new SPARQL 1.1 specifications is the SPARQL 1.1 Graph Store HTTP Protocol, which is currently still a W3C Working Draft. According to its abstract, it “describes the use of HTTP operations for the purpose of managing a collection of graphs in the REST architectural style.” Recent releases of Sesame support it, so I used that to try out some of the operations described by this spec. I managed to do GET, PUT, POST, and DELETE operations with individual named graphs, so that…

Data providers

RDF or otherwise.

While beta testing Talis’s Kasabi, I got to wondering about the data publishing market: who out there is hosting raw data, potentially charging for it and passing money along to the data’s providers? Poking around, I learned who the key names are. (Corrections welcome.) I accidentally stumbled across a few more when I followed a tweet from @xmlgrrl (a.k.a. Eve Maler, a friend of mine in the XML world since it was the SGML world) and started looking at her husband Eli’s blog.…

The following two links won’t do much if you click them now, but if you drag them to your bookmarks toolbar, clicking the first one there while viewing a Wikipedia page will take you to the corresponding DBpedia page, and clicking the second while viewing the Freebase page for a particular topic will take you to the page full of RDF for that topic.

What SKOS-XL adds to SKOS

Extra flexibility for label metadata.

In my first few glances at SKOS eXtension for Labels, I didn’t quite get it. Recently, though, while looking at a client’s requirements document at TopQuadrant, when I saw that they wanted to attach metadata to individual terms, I started modeling this in my head and then I realized I didn’t need to: SKOS-XL already had.

Converting CSV to RDF

The simplest way yet.

There are probably dozens of ways to convert comma-separated values to parsable RDF, but I recently came up with one that was so simple that I wanted to share it.