1Attean::SimpleQueryEvalUusaetrorC(o3n)tributed Perl DocuAmtetnetaant:i:oSnimpleQueryEvaluator(3)
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NAME

6       Attean::SimpleQueryEvaluator - Simple query evaluator
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VERSION

9       This document describes Attean::SimpleQueryEvaluator version 0.033
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SYNOPSIS

12         use v5.14;
13         use Attean;
14         my $algebra = Attean->get_parser('SPARQL')->parse('SELECT * WHERE { ... }');
15         my $active_graph = Attean::IRI->new('http://example.org/');
16         my $e = Attean::SimpleQueryEvaluator->new( model => $model );
17         my $iter = $e->evaluate( $algebra, $active_graph );
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DESCRIPTION

20       The Attean::SimpleQueryEvaluator class implements a simple query
21       evaluator that, given an Attean::API::Algebra and a Attean::API::Model
22       object, evaluates the query represented by the algebra using data from
23       the model, and returns a query result.
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ATTRIBUTES

26       "model"
27           The Attean::API::Model object used for query evaluation.
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29       "default_graph"
30           The Attean::API::IRI object representing the default graph in the
31           "model".  The default graph will be excluded from enumeration of
32           graph names for query features such as "GRAPH ?g {}".
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34       "request_signer"
35           If set, used to modify HTTP::Request objects used in evaluating
36           SERVICE calls before the request is made. This may be used to, for
37           example, add cryptographic signature headers to the request. The
38           modification is performed by calling "$request_signer->sign(
39           $request )".
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METHODS

42       "evaluate( $algebra, $active_graph )"
43           Returns an Attean::API::Iterator object with results produced by
44           evaluating the query $algebra against the evaluator's "model",
45           using the supplied $active_graph.
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47       "evaluate_pattern( $pattern, $active_graph, \@new_vars, \%blanks )"
48           Returns an Attean::API::Iterator object with results produced by
49           evaluating the triple- or quad-pattern $pattern against the
50           evaluator's "model", using the supplied $active_graph.
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52           If the "ground_blanks" option is false, replaces blank nodes in the
53           pattern with fresh variables before evaluation, and populates
54           %blanks with pairs ($variable_name => $variable_node). Each new
55           variable is also appended to @new_vars as it is created.
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BUGS

58       Please report any bugs or feature requests to through the GitHub web
59       interface at <https://github.com/kasei/attean/issues>.
60

SEE ALSO

AUTHOR
63       Gregory Todd Williams  "<gwilliams@cpan.org>"
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66       Copyright (c) 2014--2022 Gregory Todd Williams.  This program is free
67       software; you can redistribute it and/or modify it under the same terms
68       as Perl itself.
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72perl v5.36.0                      2023-01-19   Attean::SimpleQueryEvaluator(3)



        

    


            
        

        

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