Support for default graph as the union of all named graphs

[flamingofugang]

Hi All,

I found this feature is very helpful in our case, but it is only available for TDB backend, can we make this available for HDT files?

This service offers SPARQL query access only to a TDB database. The TDB database can have specific features set, such as making the default graph the union of all named graphs.

<#service3>  rdf:type fuseki:Service ;
    fuseki:name              "tdb" ;       # http://host:port/tdb
    fuseki:serviceQuery      "sparql" ;    # SPARQL query service
    fuseki:dataset           <#dataset> ;
    .

<#dataset> rdf:type      tdb:DatasetTDB ;
    tdb:location "DB" ;
    # Query timeout on this dataset (1s, 1000 milliseconds)
    ja:context [ ja:cxtName "arq:queryTimeout" ;  ja:cxtValue "1000" ] ;
    # Make the default graph be the union of all named graphs.
    ## tdb:unionDefaultGraph true ;
     .

[larsgsvensson]

+1 to this suggestion