/ 
Neo4j-Driver-0.15
River stage one • 1 direct dependent • 2 total dependents
/ Neo4j::Driver::Record

NAME

Neo4j::Driver::Record - Container for Cypher result values

VERSION

version 0.15

SYNOPSIS

use Neo4j::Driver;
$session = Neo4j::Driver->new->basic_auth(...)->session;

$query = 'MATCH (m:Movie) RETURN m.name, m.year';
$records = $session->run($query)->list;
foreach $record ( @$records ) {
  say $record->get('m.name');
}

$query .= ' ORDER BY m.year LIMIT 1';
$record = $session->run($query)->single;
say 'Year of oldest movie: ', $record->get(1);

DESCRIPTION

Container for Cypher result values. Records are returned from Cypher statement execution, contained within a StatementResult. A record is a form of ordered map and, as such, contained values can be accessed by either positional index or textual key.

METHODS

Neo4j::Driver::Record implements the following methods.

get

$value1 = $record->get('field_key');
$value2 = $record->get(2);

Get a value from this record, either by field key or by zero-based index.

When called without parameters, get() will return the first field. If there is more than a single field, a warning in the category `ambiguous` will be issued.

$value = $session->run('RETURN "It works!"')->single->get;
$value = $session->run('RETURN "warning", "ambiguous"')->single->get;

When retrieving values from records, Neo4j types are converted to Perl types as shown in the following table.

Neo4j type      resulting Perl type
----------      -------------------
Number          scalar
String          scalar
Boolean         JSON::PP::true or JSON::PP::false
null            undef

Node            Neo4j::Driver::Type::Node
Relationship    Neo4j::Driver::Type::Relationship
Path            Neo4j::Driver::Type::Path

List            array reference
Map             hash reference

Boolean values are returned as JSON types; use !! to force-convert to a plain Perl boolean value if necessary.

Note that early versions of this class returned nodes, relationships and paths as hashrefs or arrayrefs rather than blessed objects. This was a bug. The underlying data structure of nodes and relationships is an implementation detail that should not be relied upon. If you try to treat Neo4j::Driver::Type::Node, Neo4j::Driver::Type::Relationship or Neo4j::Driver::Type::Path objects as hashrefs or arrayrefs, your code will eventually fail with a future version of this driver.

data

$hashref = $record->data;
$value = $hashref->{field_key};

Return the keys and values of this record as a hash reference.

EXPERIMENTAL FEATURES

Neo4j::Driver::Record implements the following experimental features. These are subject to unannounced modification or removal in future versions. Expect your code to break if you depend upon these features.

column_keys

$size = $record->{column_keys}->count;
$record->{column_keys}->add('new_field_key');

Allows adding new columns to the record's field key / index resolution used by the get method. Can be used to synthesize 'virtual' fields based on other data in the result. The new fields can then be accessed just like regular columns.

graph

$nodes = $record->{graph}->{nodes};
$rels  = $record->{graph}->{relationships};

Allows accessing the graph response the Neo4j server can deliver via HTTP. Requires the return_graph field to be set on the Transaction before the statement is executed.

meta

$meta = $record->{meta};

Allows accessing the entity meta data that some versions of the Neo4j server provide via HTTP.

SEE ALSO

AUTHOR

Arne Johannessen <ajnn@cpan.org>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2016-2020 by Arne Johannessen.

This is free software, licensed under:

The Artistic License 2.0 (GPL Compatible)