Yes. triple level only

Zhe,

I have 4 rows in rdfm_owltst regardless of whether ctxt1 is populated or not.

I load the tables with these 4 rows of data and then I update them to set the ctxt1 value (ols label).

When I query using the application table owner I get all the rows whether I select directly on the app table or using sem_match.

select s,p,o from table(SEM_MATCH('(?s ?p ?o)', SEM_MODELS('OWLTST'), null,null,null));

Same thing goes for another user with the correct privileges on the app table and the model. Results are filtered correctly by OLS depending on the session label I set.

My issue is when I go to create the entailment

EXECUTE sem_apis.create_entailment('owltst_idx', sem_models('owltst'), sem_rulebases('OWLPRIME'));

Nothing gets populated in the RDFI_OWLTST_IDX view when the the triple level policy is enabled. If the ols table policy is removed (not disabled), the create_entailment statement runs and populates rdfi_owltst_idx with several rows however the ctxt1 column is null.

With rows in rdfi_owltst_idx (and after updating ctxt1 with a value) I can use the sem_match query as such

select s,p,o from table(SEM_MATCH('(?s ?p ?o)', SEM_MODELS('OWLTST'), sem_rulebases('OWLPRIME',null,null));

and I can see the inferred triples.

When ctxt1 is null on rdfi_owltst_idx I do not see the inferred triples.

What is the correct procedure to create the entailment and have it populate ctxt1? Does the ols table policy have to be removed? Chapter 5 has several options LABELGEN_RULE, LABELGEN_SUBJECT, LABELGEN_PREDICATE, LABELGEN_OBJECT, LABELGEN_DOMINIATING, or antecedent labels. Which one is correct when using triple level only ols?

The documentation does not seem clear on how to generate a label for an inferred triple when using triple level only ols.

thanks

Zhe,

I sent you an email with two .txt attachments that outline my steps. Formatting inside here was an issue

An update to this thread that took place over email. My email had several questions and Zhe responded in line (in bold)

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I mentioned in my previous email the way I am loading and accessing the triples.

* The model owner has full OLS privileges and loads the triples that are already classified with various differing classifications.
* The way I load the data (by calling char_to_label('CLASSIFICATION',ols_label)) will generate different ctxt1 values for each row depending on the classification of the row (ols_label).
* The model owner will create the entailment and as I understand now, all rows in the entailment index will have a single ctxt1 label based on this users user label.
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Note that the inference process will assign the user's label to the generated triples. And you know this already.

Let me explain the design principle behind it.

Say a user (with certain privilege) can read a subset of triples of a graph. The user can
then take out these triples that he/she can read, load them into an external, open source inference engine, and
generate inferred new triples. The user can take the generated triples and insert them back
into Oracle. Obviously, these newly inserted triples will get the user's label.

The above describes one way to perform inference. Oracle has a native
inference engine which perform inference inside the database. However,
label assignment for generated triples is the same for both approaches.

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* For others users to access the triples (including inferred triples), the model owner will grant select privileges on RDFM_OWLTST and RDFI_OWLTST_IDX.

What I am failing to understand is how, in a multi user system will OLS filter the inferred triples? If the model owner is the only user who can create an entailment and the ctxt1 column is inherited from this users session label how can I get accurate inferred triples for other users that have a different OLS user label than the model owner who created the entailment?
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Actually in this case, two entailments should be generated.

Model owner can grant access to the application table and model to users A, and B.

A creates an empty rulebase RBA. B creates an empty rulebase RBB.

Now A performs inference using something like
conn A/A
EXECUTE sem_apis.create_entailment('owltst_A_idx', sem_models('owltst'), sem_rulebases('OWLPRIME','RBA'));

And B performs inference using something like
conn B/B
EXECUTE sem_apis.create_entailment('owltst_B_idx', sem_models('owltst'), sem_rulebases('OWLPRIME','RBB'));

Because A and B are different users (say with different access privilege), they will see
different set of triples. Consequently, they will generate different inferred results.

The empty rulebases RBA and RBB are used to differentiate the signatures of the two entailments.

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* The model owner has the user label of TS:US_SPCL:US
* 2 triples in the app table are UNCLASSIFIED

1. 'http://example.com/name/John', 'http://www.w3.org/2002/07/owl#sameAs','http://example.com/name/JohnQ'
2. 'http://example.com/name/JohnQ','http://www.w3.org/2002/07/owl#sameAs','http://example.com/name/Omar'

* The model owner with the user label of TS:US_SPCL:US creates the OWLPRIME entailment and the 4 inferred rows in rdfi_owltst_idx inherit the TS:US_SPCL:US as ctxt1 label
* Another user with the user label of S:US_SPCL:US queries using the entailment created by the model owner is unable to see the inferred rows even though the rows are UNCLASSIFIED

Does my example make sense?
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Yes. Think of inference as a read followed by write procedure.