Splits the default RDF graph into named graph per subject URI (does not change the default graph)

GraphSplitter.sparql

INSERT {
  GRAPH ?graph {
    ?s ?p ?o .
  }
}
WHERE
  { { SELECT DISTINCT  ?s
      WHERE
        { ?s  ?p  ?o }
    }
    BIND(SHA1(str(?s)) AS ?sha1)
    BIND(uri(concat(str(<graphs/>), ?sha1, "/")) AS ?graph)
    ?s  ?p  ?o
  }