View source for Q0.9

=Query=

{{Query
|id=9
|name=DuplicateVolumeNumbers
|title=Duplicate CEUR-WS Volume numbers of [[Concept:Proceedings|proceedings]]
|description=List all wikidata proceedings with duplicate Volume numbers
|sparql=# Query 9 of Task 0
# see https://cr.bitplan.com/index.php?title=Q0.9
PREFIX pq: <http://www.wikidata.org/prop/qualifier/>
PREFIX p: <http://www.wikidata.org/prop/>
PREFIX schema: <http://schema.org/>
PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX wikibase: <http://wikiba.se/ontology#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>

SELECT ?volume (COUNT(?proceeding) AS ?count) (GROUP_CONCAT(DISTINCT ?proceeding; separator=", ") AS ?proceedings)
WHERE {
   # Instance of Proceedings
   ?proceeding wdt:P31 wd:Q1143604.
   # with english label
   ?proceeding rdfs:label ?proceedingLabel.
   FILTER(LANG(?proceedingLabel) = "en")
   # Part of the series
   ?proceeding p:P179 ?partOfTheSeries.
   # CEUR Workshop proceedings
   ?partOfTheSeries ps:P179 wd:Q27230297.
   # Volumes via a qualifier of the part of the series relation
   OPTIONAL { ?partOfTheSeries pq:P478 ?sVolume. }
   # Volume via volume property
   OPTIONAL { ?proceeding wdt:P478 ?volume. }

   # Consolidate volume numbers into one variable
   BIND(COALESCE(?sVolume, ?volume) AS ?volume)
}
GROUP BY ?volume
HAVING(COUNT(?proceeding) > 1)
ORDER BY DESC(?count)
|tryiturl=hJlygL
|wdqsurl=8ea4
|relevance=1
|task=Task0
|storemode=property
}}