In 2011, IBM developerWorks published an article that I wrote titled “Improve your taxonomy management using the W3C SKOS standard.” (They have always loved those “Get Better at This Thing” titles.) Several years later they took it (and a ton of other developerWorks content) down. I have republished it here as background for recent discussions about when OWL is appropriate to use and when it isn’t; more on that next month. I didn’t change anything but added a…
In my last blog entry, What is RDFS?, I described how the RDF Schema language lets you define RDF vocabularies, with the definitions themselves being RDF triples. We saw how simple class and property name definitions in a schema can, as machine-readable documentation for a dataset’s structure, provide greater interoperability for data and applications built around the same domain. Today we’ll look at how RDF schemas can store additional kinds of valuable information to add to what we…
RDFS, or RDF Schema, is a W3C standard specialized vocabulary for describing RDF vocabularies and data models. Before I discuss it further, though, I’d like to explain why the use of standardized, specialized vocabularies (whether RDFS itself or a vocabulary that someone uses RDFS to describe) can be useful beyond the advantages of sharing a vocabulary with others for easier interoperability.
I have usually assumed that people reading this blog already know what RDF is. After recent discussions with people coming to RDF from the Linked (Open) Data and Knowledge Graph worlds, I realized that it would be useful to have a simple explanation that I could point to. This builds on material from the first three minutes of my video SPARQL in 11 Minutes.
When I saw “Add support for scripting languages other than JavaScript” in the Jena release 4.0.0 release notes my first reaction was “What? I can run the arq command line SPARQL processor and call my own functions that I wrote in JavaScript?”
On page 5 of my book Learning SPARQL I described how the open source RDF processing framework Apache Jena includes command line utilities called arq and sparql that let you run SPARQL queries with a simple command line like this:
When I wrote about my first deep dive into Knowledge Graphs, I mentioned that although the term was around well before 2012, the idea of a Knowledge Graph was blessed as an official Google thing that year when one of their engineering SVPs published the article Introducing the Knowledge Graph: things, not strings. This blessing gave some focus to many members of the graph database community because they could say that what they had been doing was similar, if not the same, as what Google was…
Lately I’ve been thinking about some aspects of RDF technology that I have taken for granted as basic building blocks of dataset design but that Knowledge Graph fans who are new to RDF may not be fully aware of—especially when they compare RDF to alternative ways to build knowledge graphs. A key building block is the ability to link independently created knowledge graphs.
