Relationships between Models

Question

Relationships between Models

Kirill Krasyuk Jul '13

Created Jul '13	Last Reply Jul '13	Replies 3	Views 965	Votes 1

Kirill Krasyuk 2.4k

Jul '13

Hello! I want to understand how to deal with relationships in the model. Did everything as in this example: https://docs.phalcon.io/en/1.0.0/reference/models.html#relationships-between-models

class ConnexionData extends Model {

    public $id;
    public $clinic_id;
    public $disease_id;

    public function getSource() {
        return "connexion";
    }

    public function initialize() {
        $this->belongsTo("clinic_id", "NameSpace\Models\ClinicsData", "id", array(
            'alias' => 'clinics',
            'reusable' => true
        ));
        $this->belongsTo("disease_id", "NameSpace\Models\DiseaseData", "id", array(
            'alias' => 'disease',
            'reusable' => true
        ));
    }

}

class ClinicsData extends Model {

    public $id;
    public $name;

    public function getSource() {
        return "clinics";
    }

    public function initialize() {
        $this->hasMany("id", "NameSpace\Models\ConnexionData", "clinic_id", array(
            'alias' => 'сonnexion'
        ));
    }

class DiseaseData extends Model {

    public $id;
    public $name;

    public function getSource() {
        return "disease";
    }

    public function initialize() {
        $this->hasMany("id", "NameSpace\Models\ConnexionData", "disease_id", array(
            'alias' => 'сonnexion'
        ));
    }

I make a call from the action:

$services = ClinicsData::getClinicDiseaseData($id);
$this->view->setVar("services", $services);

public function getClinicDiseaseData($id) {
        $clinic = ClinicsData::find($id);
        foreach ($clinic->connexionData as $connexionData) {
            $results[] = $connexionData->diseasesData->name;
        }
        return $results;
    }

But the data does not take from the table (Postgres DB).

What could be wrong?

1

Andrey · Answer 1 · 2013-07-04T01:33:20-07:00

Is getClinicDiseaseData is a method of ClinicsData Model? It's not clear from your example.

If yes, then it should be static, not public method. If no, i assume that it is a part of your controller and it should be called as:

$services = $this->getClinicDiseaseData($id);

One other thing. As you made aliases for related tables, so use them:

public function getClinicDiseaseData($id) {
  $clinic = ClinicsData::findFirst($id);
  $results = array();
  foreach ($clinic->connexion as $connexionData) {
    $results[] = $connexionData->disease->name;
  }
  return $results;
}

Kirill Krasyuk · Answer 2 · 2013-07-04T01:55:49-07:00

Yes, getClinicDiseaseData is a method of ClinicsData Model.

I want to use the connection table, but it returns an empty array :(

Change method on

static function getClinicDiseaseData($id) { ... }

but I still get an empty array

Andrey · Answer 3 · 2013-07-04T02:19:13-07:00

Just add some debug messages in getClinicDiseaseData.

public function getClinicDiseaseData($id) {
  $clinic = ClinicsData::findFirst($id);
  var_dump($clinic->count()); // count of clinic rows. Should be one, but better be sure, that it is not 0.
  var_dump($clinic->connexion->count()); // count of related connexion rows.
  $results = array();
  foreach ($clinic->connexion as $connexionData) {
    $results[] = $connexionData->disease->name;
  }
  var_dump(count($results));
  die(); // extremely, but fast =)
  return $results;
}

Not the best debug messages, but they will point you to the problem place.

Kirill Krasyuk · Answer 4 · 2013-07-04T03:12:02-07:00

If you write your hands request, it returns the desired data, and through ORM - empty ...

select 
c.name,
d.*
from clinics c
inner join connexion cn on cn.clinic_id = c.id
inner join disease d on d.id = cn.disease_id 
where c.id = 2

Maybe it is better to manually write requests?

P.S. var_dump($clinic->connexion->count()); return Fatal error, and $clinic->connexion - empty.

Andrey · Answer 5 · 2013-07-04T03:53:22-07:00

Now i'm confused completely...

How your tables are named? From your Model's names they should be: clinics_data, connexion_data and disease_data. But from your plain sql query it seems that they are: clinics, connexion and disease.

If second case, then your models should be: Clinics, Connexion and Disease. And you can drop aliases from initialization.