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I recently wondered “could I run a Python script that includes the rdflib library on my Samsung Android phone?” Five minutes later, I was doing it, and about three of those minutes were spent installing Python.

OriginTrail is doing one of the most interesting combinations of blockchain technology and RDF that I have seen. In November I spoke with CTO and co-founder Branimir Rakić.

Justin Dowdy recently created an open source project to convert the metadata in a git repository to RDF, and I’ve been having some fun with it. Before getting into the details, as a brief demo I’ll start with a sample SPARQL query that I did to list all of the 2019 commits in my misc github repo:

There are a few tutorials out there about how to start up your own free-tier Amazon Web Services (AWS) Elastic Compute Cloud (EC2) instance and then run your own publicly available web server. I’ve planned for a while to try this with a Jena Fuseki triplestore and SPARQL endpoint, but I postponed it because I thought it might be complicated. It turned out to be pretty easy.

Sometimes a question pops into my head that, although unrelated to computers, could likely be answered with a SPARQL query. I don’t necessarily know the query off the top of my head and have to work it out. I’m going to discuss an example of one that I worked out and the steps that I took, because I wanted to show how I navigated the Wikidata data model to get what I wanted.

I have always loved the website Learn X in Y minutes, which provides short crash courses in several dozen programming languages plus additional topics such as set theory and git. Its home page tells us “Take a whirlwind tour of your next favorite language”; I’ll bet it’s especially popular with applicants on their way to job interviews where languages that are new to them are in the job description.

Two recent articles describe a fascinating use of SPARQL to improve data quality in a knowledge graph at the successful grocery delivery service Instacart. On Reliability Scores for Knowledge Graphs (pdf) is a short paper submitted to the 2022 ACM Web Conference in Lyon and a longer piece on Instacart’s tech blog is titled Red Means Stop. Green Means Go: A Look into Quality Assessment in Instacart’s Knowledge Graph.

In part one of this two-part series, we saw how the open source Snowman static web site generator can generate websites with data from a SPARQL endpoint. I showed how I created a sample website project with its snowman new command and then reconfigured the project to retrieve a list of artists from the Rhizome ArtBase endpoint, a repository of data about digital artworks since 1999. Here in part two I will build on that to add lists of artists’ works with links to Rhizome pages about…