Dear students:
A careful colleague of yours pointed out that there is a mistake on Slide 45 in this deck of slides:
https://moodle.r2.enst.fr/moodle/pluginfile.php/52164/mod_resource/content/1/RDF-and-PGs.pdf
As you can see, the query returns four variables, but the result shown only has two, and the ?y binding is wrong.
I apologize for this. As you can easily see:
- the result should have been a table of four columns
- the binding of ?x is correct
- the correct binding of ?y is the type of ?x, that is: nasa:Astronaut
- next, the binding of ?p should be nasa:crewOf , that is: the property that ?x has in that graph, which is not rdf:type
- next, the binding of ?o should be nasa:Apollo_13, that is: the value of ?p for that ?x.
Best,
Ioana