query: #Dutch public libraries located on a street (straat)
  SELECT DISTINCT ?item ?itemLabel ?full_address 
  ?streetLabel ?street_number ?postal_code
  
  WHERE 
  {
    ?item wdt:P31 wd:Q28564. #public library
    ?item wdt:P31 wd:Q11396180. #library branch 
    ?item wdt:P17 wd:Q55. #from the Netherlands 
  
    OPTIONAL {?item wdt:P131 ?municipality.} # located in the administrative territorial entity (P131)  
    OPTIONAL {?item wdt:P969 ?full_address .} #located at street address (P969)
    OPTIONAL {?item wdt:P669 ?street . #located on street (P669)
              ?street rdfs:label ?streetLabel.}
    OPTIONAL {?item p:P669 [pq:P670 ?street_number].} #Find  street number (P670), qualifier of P669
    OPTIONAL {?item wdt:P281 ?postal_code .} #postal code (P281)
    FILTER (lang(?streetLabel) = "nl")
    FILTER REGEX (?streetLabel, "straat$").
    SERVICE wikibase:label { bd:serviceParam wikibase:language "nl". }
  }
  
  ORDER BY ASC(?streetLabel)
  