On 27/07/13 15:59, Claude Warren wrote:
I believe that I have come across this before but I can't find my notes.
Q: is it true that DatasetFactory.creteMem() will return a dataset for which
dataset.getNamedModel("urn:x-arq:UnionGraph") will return a model but will
not contain a union of all the models in the dataset?
Yes. I've been implementing the union graph thing for memorty datasets
but it's a background task that's not ready yet. So expect it to change.
Q: is it true that TDBDataset.getNamedModel("urn:x-arq:UnionGraph") will
return a model that does contain the union of all dataset?
Yes (all named graphs in the dataset - not the default graph).
Q: is it true that the Model returned
by TDBDataset.getNamedModel("urn:x-arq:UnionGraph") will be updated as new
models are added to the dataset. (e.g.
TDBDataset ds;
Model m = ds..getNamedModel("urn:x-arq:UnionGraph");
ds.addNamedModel( "x", anotherModel );
// m will now contain the new data that is in "anotherModel"
Yes. Model are just stateless views of the database and
urn:x-arq:UnionGraph is calculated at query time. So if the database
changes, the changes show up everywhere.
Andy
)
