query-a6877835d7b2fc3fc0e9229d28eaa8db

rq turtle/ttl

category if it exists and otherwise from the commonswiki sitelink if it’s in the Category namespace. This is useless on its own, but can be used as part of a larger query. It must be used as a named subquery, because the optimizer has to be disabled for the sitelink fallback to work properly.(P373)Commons category Commons categories of items, taken from the

Use at

PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX schema: <http://schema.org/>
WITH {
  # their categories (via P373 or commonswiki sitelink, which gets a bit complicated)
  SELECT ?item ?commonsCategory WHERE {
    hint:SubQuery hint:optimizer "None". # we have to disable the optimizer for this subquery because it gets confused by the ?commonsCategoryStatementEn part
    INCLUDE %items.
    OPTIONAL {
      ?item wdt:P373 ?commonsCategoryStatement.
      BIND(STRLANG(CONCAT("Category:", ?commonsCategoryStatement), "en") AS ?commonsCategoryStatementEn)
      ?commonsCategoryFromStatement schema:name ?commonsCategoryStatementEn;
                                    schema:isPartOf <https://commons.wikimedia.org/>.
    }
    OPTIONAL {
      ?commonsCategoryFromSitelink schema:about ?item;
                                   schema:isPartOf <https://commons.wikimedia.org/>.
      FILTER(STRSTARTS(STR(?commonsCategoryFromSitelink), "https://commons.wikimedia.org/wiki/Category:"))
    }
    BIND(COALESCE(?commonsCategoryFromStatement, ?commonsCategoryFromSitelink) AS ?commonsCategory)
    FILTER(BOUND(?commonsCategory))
  }
} AS %itemsWithCommonsCategories

Query found at