Getting started

Tutorial

If you are new to Ontop and Virtual Knowledge Graphs, we encourage you to have a look at the official tutorial.

Using Ontop

Ontop is distributed under various forms. They can be downloaded on Github (opens new window), Docker Hub (opens new window), Sourceforge (opens new window) and in the Protégé plugin repository.

Mapping designer

For editing and testing your mappings, you can use our plugin of the Protégé ontology editor (opens new window). You can download the latest stable release directly from Protégé. Alternatively, pre-releases can be found on Github (opens new window) and Sourceforge (opens new window).

Limited support of advanced features

In particular, the Protégé plugin doesn't support lenses. For advanced usage, we recommend using text editors or considering commercial offerings.

Deployment

Once your mappings and your ontology are ready, you can deploy your VKG as a SPARQL endpoint. The Ontop endpoint is available both as a CLI command (ontop endpoint) and as a Docker image (opens new window).

You can also use the Ontop endpoint during development as it embeds a nice YASGUI client (opens new window) and an optional portal (since 4.0-beta-1) containing pre-defined queries.

Command Line Interface

Want to materialize your VKG, convert your mappings into R2RML, bootstrap your mappings or start a SPARQL endpoint? You can use the CLI for that. It can be found on on Github (opens new window) and Sourceforge (opens new window).

Former solutions

Historically, Ontop has been made available under other means that we don't recommend anymore.

Java API (not recommended)

It remains possible to use Ontop as a Java API through RDF4J (opens new window) although we recommend the HTTP SPARQL endpoint as a first option (think of a microservice). Why? Because such a Java API would add many dependencies to your project and constraint you to use certain versions of Java.

Ontop-rdf4j is available on Maven Central (opens new window).