# Redland RDF Application Framework - 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://purl.org/net/dajobe/

(C) Copyright 2000-2006 Dave Beckett, (C) Copyright 2000-2005 University of Bristol