DBPedia ontology and public SPARQL endpoint

Hi there!

Could anybody explain, what is the anticipated relation of the DBPedia ontology to the actual content of the public DBPedia SPARQL endpoint?

The first naive comparison of the two yields so many differences that it may even appear hard to say that they describe the same data.

Would my guess be correct that the classes that are in the ontology and are not rdf:type of any instance within the public endpoint should be present somewhere within the DBPedia data not included into the current version of the public endpoint (e.g. the classes dbo:Algorithm, dbo:Bishop, dbo:FileSystem, and many many others)?
Or - there is some other explanation -?

Re the other direction, it would be easier to accept that the SPARQL endpoint can be more technical and include a much wider scope of classes and properties.

My intention is to produce a visual query environment over DBPedia on the basis of ViziQuer tool. I could make some ad hoc choices re the supported classes and properties, however, I would prefer to understand, what is going on.

Thanks in advance for your comments!

Kārlis

Kārlis Čerāns
Leading Researcher, Institute of Mathematics and Computer Science, University of Latvia

Dear @karlisc,
DBpedia has become much more dynamic recently. We are rectifying documentation. You could read about the current release process here:

OpenLink Software (@pkleef ) posted a demo endpoint loading latest-core some days ago:

This latest-core also contains the latest version of the ontology, which is also used in the extraction. Note that we are working on persisting all ontologies on the Databus: http://archivo.dbpedia.org . Archivo is like LOV + web archive; persist and version all ontologies every 8 hours

Regarding the visualisation you are planning. A good practice is to make this part of the DBpedia Stack: https://wiki.dbpedia.org/tutorials/2nd-dbpedia-stack-tutorial which basically means that you need to create a Databus-compatible Docker which we add to https://hub.docker.com/u/dbpedia this way, the visualisation can be easily deployed by the chapters and anybody downloading DBpedia, see also: https://github.com/dbpedia/Dockerized-DBpedia

cheers.

Thanks, @kurzum for explanation and suggestions re the visualization.
If I may ask a simple question. If I pose a simple question e.g. to OpenLink SPARQL endpoint:
select distinct ?x where {?x a owl:Class.
FILTER NOT EXISTS {[] a ?x}}
LIMIT 100
I get a lot of results, including e.g. Department, Type, Algorithm, etc.
Where are the instances of these classes? Are they in a public endpoint anywhere? How can I get them for loading into my server, if they are not in latest-core?

Related with this,
how large would be the data, and how they can be obtained, that would match all classes that are instances of owl:Class within the latest-core?
What are the ways of obtaining subsets of data that go beyond latest-core?

Thanks again!
Kārlis

@karlisc these classes are for non-english data: http://mappings.dbpedia.org/index.php/Mapping_ru:Алгоритм

Latest core has en data only with several ontologies and enrichments, which are documented here: https://databus.dbpedia.org/dbpedia/collections/latest-core

We have a fused version here:

This is a merge of 140 language and Wikidata, i.e. all types. Other than that you can take this for individual languages (Wikidata is treated as a language version in DBpedia): https://databus.dbpedia.org/dbpedia/mappings/instance-types/ or this https://databus.dbpedia.org/dbpedia/wikidata/instance-types/

Thanks a lot! This clarifies the situation. One more issue:
Why there is a property dbo:rank in the ontology (as a datatype property), yet the property in the data is dbp:rank, and there is no data in triples with dbo:rank.
There are a lot of properties like this.
At the same time there are also some dbo: namespace properties in the data.