query: # Unique value constraint report for P1274: report by value
  
  SELECT
      ?value (SAMPLE(?valueLabel) AS ?valueLabel) (SAMPLE(?ct) AS ?ct)
      (GROUP_CONCAT(DISTINCT(STRAFTER(STR(?item), "/entity/")); separator=", ") AS ?items)
      (GROUP_CONCAT(DISTINCT(?itemLabel); separator=", ") AS ?itemLabels)
  WHERE    
  {
    	{ 	SELECT ?value (COUNT(DISTINCT ?item) as ?ct)
    		WHERE
    		{ 
    			?item wdt:P1274 ?value 
  		}
      	GROUP BY ?value HAVING (?ct>1) 
      	ORDER BY DESC(?ct)
      	LIMIT 100
  	}
    	?item wdt:P1274 ?value .
  	SERVICE wikibase:label {
      	bd:serviceParam wikibase:language "en" . 
      	?item rdfs:label ?itemLabel .
      	?value rdfs:label ?valueLabel .
    	}
  }
  GROUP BY ?value
  ORDER BY DESC(?ct)