Service-Link zur heutigen @digiSberlin -Veranstaltung anlässlich des #Digitaltag2025 (vgl. https://openbiblio.social/@digiSberlin/114732577091825896)
Folgender Query listet die Online-Kataloge/Online-Sammlungen der Berliner #GLAM-Einrichtungen: https://qlever.cs.uni-freiburg.de/wikidata/jGfXMD (Query powered by #qlever . Die zwei unbegrenzten property paths zwingen blazegraph in die Knie ...)
Folien zur Veranstaltung folgen ...
Spätestens jetzt, wo auch die #loc ins Fadenkreuz des Trumpismus gekommen ist, lohnt es sich vermutlich, sich zu überlegen, welche Services/Projekte der LOC man gerne auch zukünftig zur Verfügung hätte. Hier die Dinge, von denen #wikidata weiß:
(Alternative über #qlever, falls der #wdqs ins Timeout läuft: https://qlever.cs.uni-freiburg.de/wikidata/eKWkMF)
OpenStreetMap: Get the building (way/relation) that encloses a node using the QLever SPARQL endpoint.
Want the raw data? Here it is using #QLever and #OverpassUltra, exportable as #GeoJSON and in the #PublicDomain:
Want to create a time series animation like the one @bmacs001 posted, but for your favorite region? The #OSMWiki has the rudiments of a guide to creating one with {#OverpassTurbo or #OverpassUltra or #QLever} + #QGIS + #FFmpeg:
Dear @dblp, we are very happy to see that you are deploying a QLever-based SPARQL endpoint. Would you probably mind to increase your cache size as this simple 2-hop query doesn't work:
SELECT ?p ?o ?pp ?oo WHERE {
<https://dblp.org/rec/books/acm/19/X19> ?p ?o .
OPTIONAL { ?o ?pp ?oo . }
}
https://sparql.dblp.org/n9kCi4
Thank you very much!! :)
If you’ve been querying our data using #QLever, updates have resumed with some breaking changes and new features:
https://forum.openhistoricalmap.org/t/qlever-is-back-and-even-more-meta/411
And just last week, we presented at the Workshop on New Media Art Archiving, which took place at ZKM | Center for Art and Media Karlsruhe. #WNMAA2025
A blog post up on the @tibhannover blog, outlines the key topics discussed at the workshop and how current developments in #RDM on national and international level can deliver the goal of the workshop to interconnect media art archives globally. Specifically services such as #KGI4NFDI and #TS4NFDI from #Base4NFDI, in addition to tools such as #Qlever and #ORKGask provide relevant points of reference for the further development of a decentralised media art archive infrastructure.
🔗🔖 https://blog.tib.eu/2025/02/10/connecting-media-art-archives/
@JensB @VdAKluttig Die häufigsten Properties, die in Referenzen auf Bestände verwendet werden: https://qlever.cs.uni-freiburg.de/wikidata/n2Mxy9 (momentan scheint das #qlever Wikidata-Backend zu zicken ...)
Linking metadata in electronic lab notebook #OpenBIS with metadata in the
#bioimage resource #Omero: How many images are present in omero for a given sample in OpenBIS?
At #mpievolbio, to answer this and similar questions,
we map both resources to #RDF #KnowledgeGraphs using the #ontop framework,
serve the materialized #KGs via #qLever (https://qlever.cs.uni-freiburg.de) and run a #SPARQL query. Answered in no time! @nfdi4bioimage #LinkedOpenData #FAIR #MicrobialPopulationBiology @ontop
#federation with #qlever is really fantastic! You can easily supply missing information from other sources. This query get street addresses of cultural heritage institutions from #openstreetmap #osm where there is no corresponding statement on #wikidata : https://qlever.cs.uni-freiburg.de/wikidata/JlrRdL
Und hier noch Werke aus der @DNB_Aktuelles ... falls zwischen den Jahren die Scanner nicht ausgelastet sind, gäbe es hier ein paar Titel, die für eine Digitalisierung in Frage kämen: https://qlever.cs.uni-freiburg.de/dnb/BCINXd?exec=true
(der Query war für mich technisch lehrreich wegen der Föderation mit #qlever
it took me quite a while to understand that the ominous `wikibase:directClaim` in #Wikidata is basically just string replacement, so "?dc wikibase:directClaim ?prop ." stands for "FILTER ( STRSTARTS ( STR(?prop), "http://www.wikidata.org/prop/direct/" ) )
BIND( IRI(REPLACE( STR(?prop),"prop/direct/", "entity/" ) ) AS ?dc)" in plain #SPARQL .(https://w.wiki/CSc4).
Is there any documentation on these wikidata-specific functions? They are important if queries must be adapted to #qlever.
Social-Media-Accounts Berliner Museen (nach #wikidata ): https://qlever.cs.uni-freiburg.de/wikidata/2iuKFt
Also Qlever is pure magic and performance is ace.
Example federating across 3 sources: one of the #Wikibase instances from @tibosl + #Wikidata + #FactGrid - works like a charm in #Qlever, too:
https://qlever.cs.uni-freiburg.de/wikidata/BZEBw2
*We do need to sort out the literals business, to minimize the bindings, but that's homework!
#qlever 420ms, #wikidata #query service Timeout nach 60 Sek. , also mindestens Faktor 143. Keine Ahnung, was da die technischen Hintergründe sind; für die produktive Arbeit mit Wikidata ist #Blazegraph aber ein enorm limitierender Faktor.
okay, the final thing I had to learn, is that the new Apache #Jena #TDB2 uses transactions. That makes sense, but TDB did not have that, so that required more #Bacting updates. That the number of triples are reported shows that I seems to have solve most of that.
Oh, a minor thing, the Human Protein Atlas nanopublications has a small error, that #Qlever fails on:
:HumanProteinAtlas pav:versionNumber "23.0"^^xsd:integer .
But that I solve in the Qleverfile :) 7/7
