In a SPARQL query, the define input:inference clause is used to instruct the compiler to use the rules in the named rule set. For example:

SQL> rdfs_rule_set ('sample', 'rule_graph');

SQL> SPARQL
define input:inference "sample"
SELECT *
FROM <g>
WHERE {?s ?p ?o};

will include all the implied triples in the result set, using the rules in the sample rule set.

Inference can be enabled triple pattern by triple pattern. This is done with the option (inference 'rule_set') clause after the triple pattern concerned. Specifying option (inference none) will disable inference for the pattern concerned while the default inference context applies to the rest of the patterns. Note that the keyword is input:inference in the query header and simply inference in the option clause. See the examples section below for examples.

In SQL, if RDF_QUAD occurs in a select from clause, inference can be added with the table option WITH , as follows:

SPARQL
SELECT *
FROM rdf_quad table OPTION (with 'sample')
WHERE g = iri_to_id ('xx', 0);

This is about the same as:

SPARQL
define input:inference "sample"
SELECT *
FROM <xx>
WHERE {?s ?p ?o}