RDF::Query::Federate - A subclass of RDF::Query for efficient federated query execution.

This document describes RDF::Query::Federate version 2.907.

 my $service = RDF::Query::ServiceDescription->new( $url );
 my $query = new RDF::Query::Federate ( $sparql );
 $query->add_service( $service );
 my $stream = $query->execute();

...

new ( $query, \%options )

new ( $query, $base_uri, $languri, $lang )

Returns a new RDF::Query::Federate object for the specified $query. The query language defaults to SPARQLP, but may be set specifically by specifying either $languri or $lang, whose acceptable values are:

  $lang: 'rdql', 'sparql11', or 'sparql'

  $languri: 'http://www.w3.org/TR/rdf-sparql-query/', or 'http://jena.hpl.hp.com/2003/07/query/RDQL'

add_service ( $service_description )

Adds the service described by $service_description to the query's list of data sources.

services

algebra_fixup ( $algebra, $bridge, $base_uri, $ns )

Called in the fixup method of ::Algebra classes, returns either an optimized ::Algebra object ready for execution, or undef (in which case it will be prepared for execution by the ::Algebra::* class itself.

 Gregory Todd Williams <gwilliams@cpan.org>