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namedgraph
username_0
Lets say the default graph is empty. In principle it is always present in an RDF dataset, so instinctively a `GET` should return `200 OK`. But as it's formulated above, since _graph content [...] does not exist_, it could also be interpreted as `404 Not Found`.

Empty named graph vs. non-existing named graph is similarly ambiguous. A [test for non-existing graph](https://www.w3.org/2009/sparql/docs/tests/data-sparql11/http-rdf-update/#head_on_a_nonexisting_graph) is present, but not for an empty graph, as far as I can see.

**Describe the improvement**
Clarify the language in the GSP spec and add tests to the suite. This probably applies to all HTTP methods, not only `GET`.

**Additional context**
Jena Fuseki returns `200 OK` on an empty default graph, Dydra (latest upgrade) returns `404 Not Found`. Does anyone know about other implementations?
Mailing list thread: https://lists.w3.org/Archives/Public/public-sparql-dev/2020JulSep/0000.html
Clarify Graph Store Protocol status codes for empty graphs and add tests
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namedgraph
username_0
@username_1 @lisp @kasei
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afs
username_1
This topic is discussed on the sparql-dev mailing list.
Have you discussed this with the systems involved?
"X does this, Y does that" is in the first instance a support issue.
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namedgraph
username_0
Sure, but the GSP spec text is ambiguous in itself. Don't you agree?
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afs
username_1
So does the content exist? SPARQL Update has the [definition of "Graph Store"](https://www.w3.org/TR/sparql11-update/#def_graphstore). There is always a slot for the default graph and it always holds a graph.

I suppose the GSP Status code text for 404 could still apply for deployment or transient errors. The GSP Status code text is specifically written to say "there is nothing special about GSP - do the normal HTTP thing" and sometimes errors happen.
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