On 06/12/2021 08:16, Simon Gray wrote:
I see, thanks for the swift reply.
Would you agree that a decent approach could be making a secondary query into a
graph of the raw data, comparing the result sets using set
difference/intersection? The main issue I see with this approach is that the
execution time effectively becomes N*M which could be a problem for
particularly heavy queries.
Yes, you would need to test each result triple for presence in the base
graph. I'm not sure what the indexing structure of in-memory graphs in
Jena is these days but hopefully the index is good enough to bring that
down the more like mlog(n).
If this operation is a significant bottleneck then you could, in
principle, use a bloom filter to speed up the average membership test.
Dave
Den 6. dec. 2021 kl. 09.08 skrev Dave Reynolds <dave.e.reyno...@gmail.com>:
On 06/12/2021 07:57, Simon Gray wrote:
I would like to display inferred triples differently in my UI, but I’m unsure
how to programmatically ascertain which triple is from inference and which is
raw data. The only way I can think of that might work would be to make a
secondary look-up in the raw data graph and compare the difference of the
result sets, but I thought maybe there is a utility method or some kind of
attached metadata I could use on the individual triple instead.
Sorry no, there's no triples-with-inference-metadata API in jena.
There is the derivations API but that's just for drilling down into single
deductions and is way more expensive than a simple test against the base model.
With forward inference the deductions are stored separately from the base
triples (getDeductionsGraph()) but that doesn't really help you.
Dave
