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(This may look like a long blog entry, but it’s mostly sample schemas, data, and shapes. It should be a quick read.)

It’s easy enough for a SPARQL query to specify that you only want literal values that are tagged with a particular spoken language such as English or French. I had a more complex condition to express recently that has happened to me fairly often: how do I retrieve all the data for a particular resource except the literals tagged in a foreign language? I want all the triples with object property values, and I want all the ones with literal values, regardless of type, unless they are tagged…

It seems like every few months I have a project where I need to parse some JSON and pull out certain parts. Maybe the JSON came in JSON files, or maybe I retrieved it from an API. The duration between each of these occasions is long enough that I’ve had to relearn some basics each time, so a year or two ago I made a sample JSON file that demonstrates a few data structures and features, and then I wrote a Python demo script that parses them. Now I look at that script to review the basics…

A few years ago I wrote about some metadata that was 4,000 years old. Today I wanted to write about another high point in the history of metadata — well, some sort of point: the failure of Amazon’s folksonomy and the Playing with Fire album by Kevin Federline, the former Mr. Britney Spears. Throughout this discussion I’ll show some of the tags that Amazon users added to this album, and I’ll also provide a link to a page where you can see the top 100 entries. (As you’ll…

For this month’s blog entry I originally planned to create a reference for RDF serialization formats. My idea was to create a table listing all the known formats, with links to their specs (when they have one), their age, origin, a sample, and some opinionated comments–for example, why creating new documents in RDF/XML made sense in 1999 but no longer does.

In my book Learning SPARQL I often use a query for all the triples in a dataset (that is, all the triples in the default graph and all the triples in any named graphs) that I now realize needs some revision to be more accurate.

SPARQL Anything is an open source tool that lets you use SPARQL to query data in a long list of popular formats: XML, JSON, CSV, HTML, Excel, Text, Binary, EXIF, File System, Zip/Tar, Markdown, YAML, Bibtex, DOCx, and PPTx. It has a lot of great documentation and features, but I’ll start here with an example of it in action.