NAME¶
AtteanX::Store::LDF - Linked Data Fragment RDF store
SYNOPSIS¶
use v5.14;
use Attean;
use Attean::RDF qw(iri blank literal);
use AtteanX::Store::LDF;
my $uri = 'http://fragments.dbpedia.org/2014/en';
my $store = Attean->get_store('LDF')->new(start_url => $uri);
my $iter = $store->get_triples(undef,undef,literal("Albert Einstein"));
while (my $triple = $iter->next) {
say $triple->subject->ntriples_string .
" " .
$triple->predicate->ntriples_string .
" " .
$triple->object->ntriples_string .
" .";
}
DESCRIPTION¶
AtteanX::Store::LDF provides a triple-store connected to a Linked Data Fragment
server. For more information on Triple Pattern Fragments consult
<http://linkeddatafragments.org/>
METHODS¶
Beyond the methods documented below, this class inherits methods from the
Attean::API::TripleStore class.
- new( start_url => $start_url )
- Returns a new LDF-backed storage object. The required
"start_url" argument is a URL pointing
at any Linked Data Fragment. The attribure will be coerced, so it can be a
string, a URI object, etc.
- count_triples_estimate( $subject, $predicate, $object )
- Return the count of triples matching the specified subject, predicate and
objects.
- get_triples( $subject, $predicate, $object)
- Returns a stream object of all statements matching the specified subject,
predicate and objects. Any of the arguments may be undef to match any
value.
- cost_for_plan($plan)
- Returns an cost estimation for a single LDF triple based on estimates. The
cost will be in the interval 10-1000 if the supplied argument is a
AtteanX::Plan::LDF::Triple, undef otherwise.
- plans_for_algebra($algebra)
- Returns an empty plan since access_plans generates the needed plans.
SEE ALSO¶
Attean , Attean::API::TripleStore
AUTHOR¶
Patrick Hochstenbach
"<patrick.hochstenbach@ugent.be>"
Kjetil Kjernsmo <kjetilk@cpan.org>.
COPYRIGHT¶
This software is copyright (c) 2015 by Patrick Hochstenbach. This software is
copyright (c) 2016 by Patrick Hochstenbach and Kjetil Kjernsmo. This is free
software; you can redistribute it and/or modify it under the same terms as the
Perl 5 programming language system itself.