[Wikidata] You can now query the constraint violations with the Query Service

Hello all,

We started integrating the constraint violations into the Query Service. That means you can build queries using the constraint violations, with the predicate wikibase:hasViolationForConstraint. This will hopefully help you to watch better the quality of Wikidata content.

Please note that this is a first step. Not all constraint violations are exposed yet, only the ones that can be checked fast enough. We're working on having more available in WDQS.

You can base your queries on these few examples:

#10 statements with constraint violations that are currently includedSELECT * WHERE {?x wikibase:hasViolationForConstraint ?y.} LIMIT 10

Try it! https://query.wikidata.org/#%2310%20statements%20with%20constraint%20violations%20that%20are%20currently%20included%0ASELECT%20%2A%20WHERE%20%7B%0A%3Fx%20wikibase%3AhasViolationForConstraint%20%3Fy.%0A%7D%20LIMIT%2010

#Map/timeline/image grid of items that have a statement with a constraint violation#defaultView:MapSELECT DISTINCT ?item ?itemLabel ?image ?coordinate_location ?point_in_time ?date_of_birth WHERE { ?s wikibase:hasViolationForConstraint ?y. ?item ?z1 ?s. SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en". } OPTIONAL { ?item wdt:P18 ?image. } OPTIONAL { ?item wdt:P625 ?coordinate_location. } OPTIONAL { ?item wdt:P585 ?point_in_time. } OPTIONAL { ?item wdt:P569 ?date_of_birth. }}

Try it! https://query.wikidata.org/#%23Map%2Ftimeline%2Fimage%20grid%20of%20items%20that%20have%20a%20statement%20with%20a%20constraint%20violation%0A%23defaultView%3AMap%0ASELECT%20DISTINCT%20%3Fitem%20%3FitemLabel%20%3Fimage%20%3Fcoordinate_location%20%3Fpoint_in_time%20%3Fdate_of_birth%20WHERE%20%7B%0A%20%20%3Fs%20wikibase%3AhasViolationForConstraint%20%3Fy.%0A%20%20%3Fitem%20%3Fz1%20%3Fs.%0A%20%20SERVICE%20wikibase%3Alabel%20%7B%20bd%3AserviceParam%20wikibase%3Alanguage%20%22%5BAUTO_LANGUAGE%5D%2Cen%22.%20%7D%0A%20%20OPTIONAL%20%7B%20%3Fitem%20wdt%3AP18%20%3Fimage.%20%7D%0A%20%20OPTIONAL%20%7B%20%3Fitem%20wdt%3AP625%20%3Fcoordinate_location.%20%7D%0A%20%20OPTIONAL%20%7B%20%3Fitem%20wdt%3AP585%20%3Fpoint_in_time.%20%7D%0A%20%20OPTIONAL%20%7B%20%3Fitem%20wdt%3AP569%20%3Fdate_of_birth.%20%7D%0A%7D

#Bar chart of statements that have a constraint violation, grouped by instance of the regarding item:#defaultView:BarChart#TEMPLATE={ "template": { "en": "Bar chart of statements that have a constraint violation grouped by ?property the regarding item" }, "variables": { "?property": { "query":"SELECT ?id WHERE { VALUES ?id { wd:P31 wd:P17 wd:P571 wd:P361 wd:P19 } }" } } }SELECT ?instance_ofLabel (COUNT(?instance_ofLabel) AS ?count) WHERE { ?s wikibase:hasViolationForConstraint ?y. ?item ?z1 ?s. BIND(wdt:P31 AS ?property) SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en". } OPTIONAL { ?item ?property ?instance_of. }}GROUP BY ?instance_ofLabelORDER BY DESC(?count)LIMIT 30

Try it! https://query.wikidata.org/#%23Bar%20chart%20of%20statements%20that%20have%20a%20constraint%20violation%2C%20grouped%20by%20instance%20of%20the%20regarding%20item%3A%0A%23defaultView%3ABarChart%0A%23TEMPLATE%3D%7B%20%22template%22%3A%20%7B%20%22en%22%3A%20%22Bar%20chart%20of%20statements%20that%20have%20a%20constraint%20violation%20grouped%20by%20%3Fproperty%20the%20regarding%20item%22%20%7D%2C%20%22variables%22%3A%20%7B%20%22%3Fproperty%22%3A%20%7B%20%22query%22%3A%22SELECT%20%3Fid%20%20WHERE%20%7B%20VALUES%20%3Fid%20%7B%20%20wd%3AP31%20wd%3AP17%20wd%3AP571%20wd%3AP361%20wd%3AP19%20%7D%20%7D%22%20%7D%20%7D%20%7D%0ASELECT%20%3Finstance_ofLabel%20%28COUNT%28%3Finstance_ofLabel%29%20AS%20%3Fcount%29%20WHERE%20%7B%0A%20%20%3Fs%20wikibase%3AhasViolationForConstraint%20%3Fy.%0A%20%20%3Fitem%20%3Fz1%20%3Fs.%0A%20%20BIND%28wdt%3AP31%20AS%20%3Fproperty%29%0A%20%20SERVICE%20wikibase%3Alabel%20%7B%20bd%3AserviceParam%20wikibase%3Alanguage%20%22%5BAUTO_LANGUAGE%5D%2Cen%22.%20%7D%0A%20%20OPTIONAL%20%7B%20%3Fitem%20%3Fproperty%20%3Finstance_of.%20%7D%0A%7D%0AGROUP%20BY%20%3Finstance_ofLabel%0AORDER%20BY%20DESC%28%3Fcount%29%0ALIMIT%2030

The modules included on the property talk pages, Module:Constraints https://www.wikidata.org/wiki/Module:Constraints, Module:Constraints/SPARQL https://www.wikidata.org/wiki/Module:Constraints/SPARQL etc. has been updated with a new query link (thanks Matěj!)

See also:

- the adding to the ontology https://gerrit.wikimedia.org/r/#/c/mediawiki/extensions/Wikibase/+/449329/1/docs/ontology.owl - the Phabricator ticket https://phabricator.wikimedia.org/T192567, if you have any issue to report

If you have any question, feel free to ping me.