The ‘hidden’ connections in Google’s Knowledge Graph

As far as I know, the only way to query Google’s Knowledge Graph currently is the search API. Let’s run a query on it, search for instance for Miles Davis’ album “Sketches of Spain”.<your_key_here>&limit=1 The API returns this JSON-LD fragment back (thanks, Jos de Jong for the great JSON Editor Online): Strip out the wrapping entities and each search result […]

QuickGraph#3 A step-by-step example of RDF to Property Graph transformation

The dataset For this example I am going to use a sample movie dataset from the Cayley project. It’s a set of half a million triples about actors, directors and movies that can be downloaded here. Here is what the dataset looks like: </en/meet_the_parents> <name> “Meet the Parents” . </en/meet_the_parents> <type> </film/film> . </en/meet_the_parents> </film/film/directed_by> </en/jay_roach> . […]

QuickGraph#2 How is Wikipedia’s knowledge organised

The dataset For this QuickGraph I’ll use data about Wikipedia Categories. You may have noticed at the bottom of every Wikipedia article a section listing the categories it’s classified under. Every Wikipedia article will have at least one category, and categories branch into subcategories forming overlapping trees. It is sometimes possible for a category (and the Wikipedia hierarchy is an example of […]

Importing RDF data into Neo4j

The previous blog post might have been a bit too dense to start with, so I’ll try something a bit lighter this time like importing RDF data into Neo4j. It asumes, however, a certain degree of familiarity with both RDF and graph databases. There are a number of RDF datasets out there that you may […]

Building a semantic graph in Neo4j

There are two key characteristics of RDF stores (aka triple stores): the first and by far the most relevant is that they represent, store and query data as a graph. The second is that they are semantic, which is a rather pompous way of saying that they can store not only data but also explicit descriptions of the meaning of […]