2014

Querying aggregated Walmart and BestBuy data with SPARQL

From structured data in their web pages!

The combination of microdata and schema.org seems to have hit a sweet spot that has helped both to get a lot of traction. I’ve been learning more about microdata recently, but even before I did, I found that the W3C’s Microdata to RDF Distiller written by Ivan Herman would convert microdata stored in web pages into RDF triples, making it possible to query this data with SPARQL. With major retailers such as Walmart and BestBuy making such data available on—as far as I can tell—every…

Dropping OPTIONAL blocks from SPARQL CONSTRUCT queries

And retrieving those triples much, much faster.

While preparing a demo for the upcoming Taxonomy Boot Camp conference, I hit upon a trick for revising SPARQL CONSTRUCT queries so that they don’t need OPTIONAL blocks. As I wrote in the new “Query Efficiency and Debugging” chapter in the second edition of Learning SPARQL, “Academic papers on SPARQL query optimization agree: OPTIONAL is the guiltiest party in slowing down queries, adding the most complexity to the job that the SPARQL processor must do to find the relevant…

A schemaless computer database in 1965

To enable flexible metadata aggregation, among other things.

I’ve been reading up on America’s post-war attempt to keep up the accelerated pace of R&D that began during World War II. This effort led to an infrastructure that made accomplishments such as the moon landing and the Internet possible; it also led to some very dry literature, and I’m mostly interested in what new metadata-related techniques were developed to track and share the products of the research as they led to development.

"Experience in SPARQL a plus"

The long tail story of SPARQL success: appearances in job postings.

When people talk about semantic web or linked data success stories, they usually talk about the big, well-known projects such as those at BestBuy, the BBC, NASA, life sciences companies, the whole vocabulary and taxonomy management industry, and the growing use of DBpedia by a range of companies. I’ve always found that a company’s job postings provide interesting clues about their potential technology directions, and the increasing references to SPARQL in these postings is another…