Question: Who is called Dana?
SPARQL:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX prop: <http://dbpedia.org/property/>
SELECT DISTINCT ?uri ?string
WHERE 
{
      { ?uri rdf:type foaf:Person.        
        ?uri foaf:givenName 'Dana'@en. }
      UNION 
      { ?uri prop:alias ?alias . 
        FILTER regex(?alias,'Dana') . }
       OPTIONAL {?uri rdfs:label ?string . FILTER (lang(?string) = 'en') }       
}