A union graph built up in that way won't pull in a different way from disk to memory than using just the on-disk resource would. It will find triples in one graph and in the other and merge them; it will not set up any new data structures holding triples on its own account.
ajs6f > On May 13, 2019, at 6:54 AM, 刑天 <[email protected]> wrote: > > Sorry for my poor written English... > > > My question is simple: > I have a unioned default graph which backed by two different graphs: one for > tdb, and one for memory. I only made queries using default graph, how can > jena knows when to query a tdb, and when to query a memory db. Is jena loads > everything in memory for this situation? > > > this is the assembler: > > > @prefix : <http://base/#> . > @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> . > @prefix tdb: <http://jena.hpl.hp.com/2008/tdb#> . > @prefix tdb2: <http://jena.apache.org/2016/tdb#> . > @prefix ja: <http://jena.hpl.hp.com/2005/11/Assembler#> . > @prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> . > @prefix fuseki: <http://jena.apache.org/fuseki#> . > > > :service_tdb_all a fuseki:Service ; > rdfs:label "TDB2 test" ; > fuseki:dataset :dataset ; > fuseki:name "test" ; > fuseki:serviceQuery "query" , "sparql" ; > fuseki:serviceReadGraphStore "get" ; > fuseki:serviceReadWriteGraphStore > "data" ; > fuseki:serviceUpdate "update" ; > fuseki:serviceUpload "upload" . > > > :dataset a ja:RDFDataset ; > ja:defaultGraph :unioned_model ; > . > > > :unioned_model > a ja:UnionModel ; > ja:subModel <#graph> ; > ja:subModel <#ontology> ; > . > > > <#graph> rdf:type tdb:GraphTDB ; > tdb:dataset :tdb_dataset_readwrite ; > . > > > :tdb_dataset_readwrite > a tdb:DatasetTDB ; > tdb:location "/Users/gaozhixin/example_tdb" . > > > <#ontology> rdf:type ja:MemoryModel ; > ja:content [ja:externalContent <file:/Users/gaozhixin/example.ttl> ] ;
