---
name: "RDF::Redland::Query"
section: "3pm"
platform: "linux"
package: "librdf-perl"
version: "1.0.17.1+dfsg-6+b6"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/RDF::Redland::Query"
---

# RDF::Redland::Query(3pm)

Redland RDF Syntax 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

RDF::Redland::QueryResults

## AUTHOR

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