Property mapping

[paulduchesne]

While testing working with RDF exports from the test Wikibase, I was curious about how property mappings seem to be applied. As can be seen here the mapping for items is being applied to the entity (https://rdf.wikibase.wiki/entity/) as expected, however with an example property mapping here (owl:sameAs rdf:type) seems to be applied to a blank node (of type owl:Restriction)?

This is reflected in the triplestore when querying any existing sameAs statements:

[malberts]

Can you perhaps manually edit the ttl file, or just the important part, to show an example of what it is supposed to look like?

[paulduchesne]

Absolutely, queries would normally use the /prop/direct value, so I believe in the case of https://rdf.wikibase.wiki/wiki/Special:EntityData/P3.ttl we would be expecting the owl:sameAs statement to be removed from the blank node and added to the "wdt" subject as so:

wdt:P3 a owl:ObjectProperty .

becomes

wdt:P3 a owl:ObjectProperty ;
	owl:sameAs <https://example.org/some_property> .

[malberts]

Currently I am able to add that node, but I have not yet found a way to replace the existing node. Would this (partial) example be valid with the duplicate wdt:P4 node? This seems to be valid ttl syntax, but I'm not sure if this is going to cause any problems when you start querying it.

wdt:P4 a owl:ObjectProperty .

...

wdno:P4 a owl:Class ;
	owl:complementOf _:c298799f0cd3665c958b9d4edf0ffbf3 .

_:c298799f0cd3665c958b9d4edf0ffbf3 a owl:Restriction ;
	owl:onProperty wdt:P4 ;
	owl:someValuesFrom owl:Thing .

wdt:P4 a owl:ObjectProperty ;
	owl:sameAs <http://wwww.w3.org/2000/01/rdf-schema#subClassOf> .

[paulduchesne]

I don't believe this should cause any problems, as the tripestore should just ignore duplicate triples, which is what I understand is the concern with this method?

[malberts]

Yes, that's the only concern. This code has been deployed now and you can see it here:
https://rdf.wikibase.wiki/wiki/Special:EntityData/P1.ttl

[JeroenDeDauw]

On Telegram, @paulduchesne confirmed things are working as expected now.