Hey Michael, when querying Wikidata, you need to use the item's concept URI and not just its Q-number. The following query will bring you the result you want: All the best David

PREFIX ira:https://ir-authorities.wikibase.cloud/entity/ PREFIX irp:https://ir-authorities.wikibase.cloud/prop/direct/ PREFIX wdt:http://www.wikidata.org/prop/direct/

SELECT ?person ?wikidataQNumber ?country WHERE { ?person irp:P20 ira:Q174; # is a human irp:P2 ?wikidataQNumber. # wikidata identifier BIND(URI(CONCAT("http://www.wikidata.org/entity/", ?wikidataQNumber)) AS ?wikidataURI). OPTIONAL { SERVICE https://query.wikidata.org/sparql { ?wikidataURI wdt:P27 ?country. } } }

-----Ursprüngliche Nachricht----- Von: Michael Lindsey mlindsey@berkeley.edu Gesendet: Mittwoch, 8. März 2023 18:21 An: wikibaseug@lists.wikimedia.org Betreff: [Wikibase] outbound SERVICE to Wikidata?

Hi all, I don't see my Monday post in the list archives, so I can't amend it. I am attempting to bring a wikidata property, if present, into query results on my wikibase.cloud instance, but am getting nothing. I have managed to create what I think is the simplest code to demonstrate my problem. The below query ( https://tinyurl.com/2f8wzeoj ) executes without error. Am I missing something, or can we not use Wikidata as a SERVICE? Thanks for any insight you may have! Michael Lindsey UC Berkeley School of Law

PREFIX ira:https://ir-authorities.wikibase.cloud/entity/ PREFIX irp:https://ir-authorities.wikibase.cloud/prop/direct/ PREFIX wdt:http://www.wikidata.org/prop/direct/

SELECT ?person ?wikidataQNumber ?country WHERE { ?person irp:P20 ira:Q174; # is a human irp:P2 ?wikidataQNumber. # wikidata identifier OPTIONAL { SERVICE https://query.wikidata.org/sparql { ?wikidataQNumber wdt:P27 ?country. } } } _______________________________________________ Wikibase Community User Group mailing list -- wikibaseug@lists.wikimedia.org To unsubscribe send an email to wikibaseug-leave@lists.wikimedia.org

Hi Michael,

Your wikidataQnumber is not an IRI that refers to the item of Wikidata.

Try:

PREFIX ira:https://ir-authorities.wikibase.cloud/entity/ PREFIX irp:https://ir-authorities.wikibase.cloud/prop/direct/ PREFIX wdt:http://www.wikidata.org/prop/direct/

SELECT ?person ?wikidataQNumber ?country WHERE { ?person irp:P20 ira:Q174; # is a human irp:P2 ?wikidataQNumber. # wikidata identifier BIND(IRI(CONCAT("http://www.wikidata.org/entity/%22,?wikidataQNumber)) as ?q ) OPTIONAL { SERVICE https://query.wikidata.org/sparql { ?q wdt:P27 ?country. } } }

On Thu, Mar 9, 2023 at 8:51 PM Michael Lindsey mlindsey@berkeley.edu wrote:

Hi all, I don't see my Monday post in the list archives, so I can't amend it. I am attempting to bring a wikidata property, if present, into query results on my wikibase.cloud instance, but am getting nothing. I have managed to create what I think is the simplest code to demonstrate my problem. The below query ( https://tinyurl.com/2f8wzeoj ) executes without error. Am I missing something, or can we not use Wikidata as a SERVICE? Thanks for any insight you may have! Michael Lindsey UC Berkeley School of Law

PREFIX ira:https://ir-authorities.wikibase.cloud/entity/ PREFIX irp:https://ir-authorities.wikibase.cloud/prop/direct/ PREFIX wdt:http://www.wikidata.org/prop/direct/

SELECT ?person ?wikidataQNumber ?country WHERE { ?person irp:P20 ira:Q174; # is a human irp:P2 ?wikidataQNumber. # wikidata identifier OPTIONAL { SERVICE https://query.wikidata.org/sparql { ?wikidataQNumber wdt:P27 ?country. } } } _______________________________________________ Wikibase Community User Group mailing list -- wikibaseug@lists.wikimedia.org To unsubscribe send an email to wikibaseug-leave@lists.wikimedia.org