sparql.pl

 sparql_query(+Query, -Reply, +Options)

Where Query is either a SPARQL query text or a parsed query. Reply depends on the type of query:

SELECT	row(Col1, Col2, ....)
CONSTRUCT	rdf(S,P,O)
DESCRIBE	rdf(S,P,O)
ASK	Reply == true or failure of pred

Options are:

entailment(Entailment)

Specify the entailment module used. The default is controlled by the setting sparql:entailment.

base_uri(Base)

Specify the base IRI to use for parsing the query

type(-Type)

Returns one of select(-VarNames), construct, describe or ask.

ordered(-Bool)

True if query contains an ORDER BY clause

distinct(-Bool)

True if query contains a DISTINCT clause

 sparql_compile(+Query, -Compiled, +Options)

Performs the compilation pass of solving a SPARQL query. Splitting serves two purposes. The result of the compilation can be cached if desired and through Options we can get information about the parsed query.

 optimise(+Parsed, -Optimised, +Options) is det[private]

Perform sparql query optimization using rdf_optimise/2. Currently, UPDATE requests are not optimized.

To be done

- The UPDATE modify requests involve a query and must be optimized.

 optimise_eval(+Goal0, -Goal) is det[private]

Perform partial evaluation on sparql_true/1 and sparql_eval/2 goals.

 annotate_variables(+Goal, -Vars) is det[private]

Annotate variables that appear in Goal. The annotation is a variable attribute named annotations and the value of this attribute is a list of annotations.

 optimise_eval(+GoalIn, -GoalOut)[private]

 sparql_run(+Compiled, -Reply) is nondet

Runs a compiled SPARQL query, returning the result incrementally on backtracking. Provided there are no errors in the SPARQL implementation the only errors this can produce are resource-related errors.

 select_results(+Spec, -Reply, :Goal)[private]

Apply ordering and limits on result-set.

To be done

- Handle reduced

 select_result(+Bindings, -Row, -Names) is det[private]

Transform the list Bindings of the form Name=Var into a Row term of the form row(Col1, Col2, ...) and a term names(Name1, ...). For example:

?- select_result([x=1,y=2], Row, Names).
Row = row(1,2), Names = names(x,y)

 sparql_describe(+IRI, -Triple)[private]

Return -on backtracking- triples that describe IRI. The documentation does not specify which triples must be returned for a description. As a way to get started we simply return all direct properties.