Using CakePHP 2 to make one more foreign key hop to fetch data

Question

All of the respective model associations have been configured correctly on my end.

Here's my database SQL script so you can easily see the foreign key associations:

create table proveedors 
(
    id int primary key AUTO_INCREMENT,
    nombre varchar(256)
);

create table libros 
(
    id int primary key AUTO_INCREMENT,
    proveedor_id int,
    FOREIGN KEY (proveedor_id) REFERENCES proveedors(id),
    titulo varchar(1024),
    autor varchar(512)
);

create table materias 
(
    id int primary key AUTO_INCREMENT,
    nombre varchar(1024),
    version varchar(8)
);

create table libros_materias
(
    id int primary key AUTO_INCREMENT,
    materia_id int,
    FOREIGN KEY (materia_id) REFERENCES materias(id),
    libro_id int,
    FOREIGN KEY (libro_id) REFERENCES libros(id)
);

Here's a query I'm running:

# Buscar todos los libros asociados a esta materia.
$libros = $this->LibrosMateria->findAllByMateriaId($id);
$this->set('libros', $libros);

Right now it's fetching all data correctly as expected; I just need to make the query do one more little hop and get me the Proveedor's name.

The current query is returning this:

(int) 0 => array(
    'LibrosMateria' => array(
        'id' => '2',
        'materia_id' => '1',
        'libro_id' => '1'
    ),
    'Materia' => array(
        'id' => '1',
        'tipo_materia_id' => '1',
        'sigla' => 'MKT-111',
        'nombre' => 'Direccion de Marketing',
        'version' => '3-2012'
    ),
    'Libro' => array(
        'id' => '1',
        'proveedor_id' => '1',
        'titulo' => 'PHP 2.0',
        'autor' => 'Arhari',
        'edicion' => '3ra Edicion',
        'isbn' => '0912309',
        'cantidad_de_paginas' => '912',
        'fecha_de_publicacion' => '2012-10-08',
        'portada' => null
    )
),

I can see it's making 1 single foreign key hop, but not going further. Is there some way for CakePHP to do this? Any suggestions? Remeber: My model associations are set up correctly.

Answer 1

Try changing your query from:

$libros = $this->LibrosMateria->findAllByMateriaId($id);

to:

$libros = $this->LibrosMateria->findAllByMateriaId($id, array(), array(), null, null, 2);

Here you are setting the $recursive field to be 2, which should retrieve the information you want.

For more information see http://book.cakephp.org/2.0/en/models/retrieving-your-data.html#findallby