Federated update (COPY)

[VladimirAlexiev]

I want to copy a graph from one repo to another.

The SPARQL Graph Protocol has respective operations (GET, PUT, POST)
(though I need to sequence them manually: GET and save as file; POST using that file's content).

But I think it's a valid use case to be able do that in SPARQL.
There are data workflows with electrical CIM that involve materialization of Difference models and reasoning, where COPY (maybe even other Update operations) across repos would be very useful.

No known workaround, since federation (SERVICE) doesn't support named graphs.

[kasei]

No known workaround, since federation (SERVICE) doesn't support named graphs.

Can you expand on this? The active graph isn't supported by SERVICE, but you can use named graph patterns inside a SERVICE block, and results coming back from a federated request are just variable bindings, so orthogonal to graphs, named or otherwise.

[afs]

What about:

LOAD <http://otherHost/database?graph=http://example/source> ## into default graph

LOAD <http://otherHost/database?default> INTO here:graphName

[VladimirAlexiev]

@kasei you're right, my mistake.

@afs This syntax sounds ok, but how about syntax for MOVE?
Of course, one would need to authenticate to the external service:

• add Authentication to Federation #117

[afs]

but how about syntax for MOVE?

MOVE is composite : it is LOAD then DELETE.

There are no distributed transactions so the initiator has to manage the failure modes.