Hi Kevin,
The configuration setting you are looking for is "union default graph"
With this, the default graph of the dataset is a view of the union of
all the named graphs.
for TDB2 (TDB1 is similar), the server configuration would include
something like:
:dataset_tdb2 rdf:type tdb2:DatasetTDB2 ;
tdb2:location "DB2" ;
tdb2:unionDefaultGraph true ;
.
Andy
https://jena.apache.org/documentation/tdb2/tdb2_fuseki.html
On 13/07/2021 06:35, Perry, Kevin wrote:
Hi!
We're currently extending an application using both Metaphactory and
Blazegraph to also support Jena, or more specifically Fuseki.
In a perfect world, we'd be using the exact same SPARQL queries for
both Fuseki and Blazegraph.
Unfortunately we hit a bit of a snag when it comes to the handling of
the default and named graphs[1].
We are used to not including a GRAPH clause in our queries and
receiving results from all graphs (i.e. both from the default and named
graphs).
With Fuseki, we only get results from either the default graph or any
named graph matching a GRAPH clause.
Is there some *configuration setting* (or maybe something equally
trivial) to have Fuseki behave similarly to Blazegraph in this respect?
At least according to the article[1], there is supposed to be a setting
("[...] Apache Jena offer options to change their default behavior"),
but it unfortunately doesn't go into more detail.
On the long run, we do intend to rework the queries and how we store
data (i.e. putting everything into named graphs) but unfortunately
that's not something we can afford to do right away.
Kevin
[1] https://blog.metaphacts.com/the-default-graph-demystified
