Way to assign graph or context while importing file?

[DenisNovac]

Hi everyone. I can see that blazegraph uses graphs since query

prefix skos: <http://www.w3.org/2004/02/skos/core#>
prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>


SELECT DISTINCT ?graph
WHERE {
  BIND (skos:prefLabel AS ?p)
  GRAPH ?graph {
    { ?s rdf:type skos:Concept . }
    OPTIONAL { ?s ?p ?o . }  
  }

returns bd:nullGraph. But is it configurable during file importing? In my previous rdf store there was a feature where you could assign the context/graph to every triple in file.