User:TweetsFactsAndQueries/Queries/longest rivers that feed into another river

Originally posted on Twitter and on Mastodon.

SELECT ?river ?riverLabel (?lengthInM/1000 AS ?lengthInKm) ?mouthLabel WITH {
  SELECT DISTINCT ?river ?lengthInM ?mouth WHERE {
    ?river wdt:P31/wdt:P279* wd:Q4022;
           wdt:P403 ?mouth;
           p:P2043 ?lengthStatement. ?lengthStatement a wikibase:BestRank; psn:P2043/wikibase:quantityAmount ?lengthInM. hint:Prior hint:rangeSafe true.
    ?mouth wdt:P31/wdt:P279* wd:Q4022.
    FILTER(?lengthInM > 1000000)
  }
  ORDER BY DESC(?lengthInM)
  LIMIT 10
} AS %results WHERE {
  INCLUDE %results.
  SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en". }
}
ORDER BY DESC(?lengthInM)

Try it!