class SPARQL::Algebra::Operator::Project
The SPARQL
GraphPattern `project` operator.
@example
(select (?v) (project (?v) (filter (= ?v 2) (bgp (triple ?s <http://example/p> ?v)))))
Constants
- NAME
Public Instance Methods
execute(queryable, **options, &block)
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Executes this query on the given `queryable` graph or repository. Reduces the result set to the variables listed in the first operand
@param [RDF::Queryable] queryable
the graph or repository to query
@param [Hash{Symbol => Object}] options
any additional keyword options
@yield [solution]
each matching solution
@yieldparam [RDF::Query::Solution] solution @yieldreturn [void] ignored @return [RDF::Query::Solutions]
the resulting solution sequence
@see www.w3.org/TR/sparql11-query/#sparqlAlgebra
# File lib/sparql/algebra/operator/project.rb, line 33 def execute(queryable, **options, &block) @solutions = queryable.query(operands.last, depth: options[:depth].to_i + 1, **options) @solutions = @solutions.project(*(operands.first)) @solutions.each(&block) if block_given? @solutions end