Redland librdf Language Bindings - Perl RDF::Redland::Query Class

NAME

RDF::Redland::Query - Redland RDF Syntax Query Class

SYNOPSIS

  use RDF::Redland;

  ...
  my $query=new RDF::Redland::Query($query_string); # default query language
  my $results=$query->execute($model);
  # or my $results=$model->query_execute($query);
  while(!$results->finished) {
    for (my $i=0; $i < $results->bindings_count(); $i++) {
      my $name=$results->binding_name($i);
      my $value=$results->binding_value($i);
      # ... do something with the results
    }
    $results->next_result;
  }

DESCRIPTION

This class represents queries of various syntaxes over an RDF::Redland::Model returning a sequence of results that (currently) bind variable names to RDF::Redland::Node values.

CONSTRUCTORS

new QUERY-STRING [BASE-URI [QUERY-LANG-URI [QUERY-LANG]]]

Create a new RDF::Redland::Query object for a query string QUERY-STRING with optional base URI BASE-URI IN QUERY language QUERY-LANG or query language URI QUERY-LANG-URI (both can be undef). If QUERY-LANG-URI is omitted, the current directory is used as the base URI. If QUERY-LANG-NAME is undef, the default query language "rdql" is used. If BASE-URI is omitted, no base URI is used.

METHODS

execute MODEL

Run the query against model MODEL returning a RDF::Redland::QueryResults object or undef on failure.

SEE ALSO

the RDF::Redland::QueryResults manpage

AUTHOR

Dave Beckett - http://www.dajobe.org/

(C) Copyright (C) 2000-2011 Dave Beckett, (C) Copyright (C) 2000-2005 University of Bristol