Contacts
Ladislav Peška, S208, peska@ksi.mff.cuni.cz
- Intro to SPARQL:
link 1, querying over LOD
link, older slides
link,
- DBPedia
DBPedia: machine readable version of Wikipedia, RDF data format, available SPARQL endpoint.
Several language mutations English, Czech
Plenty of other datasets, not always SPARQL available. list of datasets.
- How to travers DBPedia
Start from Wikipedia + modify URL (wiki => resource), traverse through pages
. DBPedia has ontology (not very usefull: duplicity, redundancy, outdated)
- search for rdf:types
- browse entities of given type
- describe entity, compare with original wiki page
- SPARQL queries
- visualize relations
- SPARQL query constructions
- What dit Ivan Olbracht wrote? //basic graph patterns
- What did the autor of R.U.R. wrote, when and what are the genre of these works? //complex graph patterns, optional
- Where were Sci-FI authors born, most often? //group by, order by
- Which larger towns (above 20000 inhabitants) are in Southern-bohemia shire? //filter (numerical)
- What are the professions of persons named "Zeman"? //filter (regex)
- Which actors shot most succesful movies? Movies with highest profit? //basic arithmetics, order by, group by, BIND
What else do you want to know
some results