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laravelmodelbelongs-tohas-one

Laravel 5.6.17 Model hasOne over multiple tables


I'm quite new to Laravel and now I'm trying to move parts of a former application from a small self written framework into Laravel. The address book is multilingual therefor the table structure is a little more complicated.

db-structure

And this is my source code:

  • AddressBookController.php
        namespace App\Http\Controllers;

        use App\AddressBook as AB;
        use Illuminate\Http\Request;
        use Illuminate\Support\Facades\Validator;

        class AddressBookController extends Controller
        {
            /**
             * Display a listing of the resource.
             *
             * @return \Illuminate\Http\Response
             */
            public function index()
            {
                $entries = AB::all();

                return view('addressBook')->with([
                    'class' => __CLASS__,
                    'function' => __FUNCTION__,
                    'line' => __LINE__,
                    'entries' => $entries,
                ]);
            }
        }
  • Model AddressBook.php

        namespace App;
    
        use Illuminate\Database\Eloquent\Model;
    
    
        class AddressBook extends Model
        {
            protected $table = 'address';
            protected $primaryKey = 'address_id';
            protected $keyType = 'int';
            public $incrementing = true;
            public $timestamps = false;
            protected $searchable = [
                'columns' => [
                    'address.address_surname' => 10,
                    'address.address_company' => 5,
                    'address.address_vatid' => 2,
                ],
            ];
    
            public function country() {
                return $this->hasOne('country', 'country_id', 'country_id');
            }
    
            public function addresstype() {
                return $this->hasOne('addresstype', 'addresstype_id', 'addresstype_id');
            }
        }
    
  • Model Country.php

        namespace App;
    
        use Illuminate\Database\Eloquent\Model;
    
        class Country extends Model
        {
            protected $table = 'country';
            protected $primaryKey = 'country_id';
            protected $keyType = 'int';
            public $incrementing = true;
            public $timestamps = false;
    
            public function translation() {
                return $this->hasOne('translations', 'translations_id', 'translations_id');
            }
    
            public function addressbook() {
                return $this->belongsTo('address', 'country_id', 'country_id');
            }
        }
    
  • Model AddressType

        namespace App;
    
        use Illuminate\Database\Eloquent\Model;
    
        class AddressType extends Model
        {
            protected $table = 'addresstype';
            protected $primaryKey = 'addresstype_id';
            protected $keyType = 'int';
            public $incrementing = true;
            public $timestamps = false;
    
            public function translation() {
                return $this->hasOne('translations', 'translations_id', 'translations_id');
            }
    
            public function addressbook() {
                return $this->belongsTo('address', 'addresstype_id', 'addresstype_id');
            }
        }
    
  • Model Translation.php

        namespace App;
    
        use Illuminate\Database\Eloquent\Model;
    
        class Translation extends Model
        {
            protected $table = 'translations';
            protected $primaryKey = 'translations_id';
            protected $keyType = 'int';
            public $incrementing = true;
            public $timestamps = false;
    
            public function country() {
                return $this->belongsTo('country', 'translations_id', 'translations_id');
            }
    
            public function addresstype() {
                return $this->belongsTo('addresstype', 'translations_id', 'translations_id');
            }
        }
    

The request "$entries = AB::all();" works in general but I get the id's and maybe I'm completely wrong here but I thought that data from foreign keys will be replaced with the respective models (if configured correctly). so my question is:

a. did I make a mistake during configuration and if yes, where exactly is the error?
or
b. is my assumption of replacing id's with objects is completly wrong?

Thanks in advance! Steve


Solution

  • Laravel Eloquent models do not replace the foreign keys of the active records with the relational data, it only appends a new property with the same name as the method relating the classes and in that property it puts all the Model instances of the resulted query, this ONLY if you access the property, its called Eager Loading.

    It is explained here (Ofiicial Documentation)

    $addressBook = App\AddressBook::find(1); //this only will return the active record with the id 1  and nothig more.
    
    $addressBook->country; // The property "country" does not exist in the AddressBook Classs but eloquent models will return a "fake" property with the value of the result of the query by the method with the same name (only if the method returns an Eloquent Relation).
    

    This Eloquent behavior is natural, and is a very clever way to minimize the number of queries, Eloquent will never load a relation if there is no need to.

    If you want to load a relation in a set the models at the same time that those models are retriving from the db you need to explicitly especify wich relations you want to load.

    $addressBook = App\AddressBook::with(['country', 'addresstype', 'anotherRelation'])->get(); // this will retrive all the addressBook models and in each one will attach the relations specified.
    

    [EDITED] Also you have to place the entire namespace of the related model class in the relation methods so you need to replaced like:

        class Translation extends Model
        {
            protected $table = 'translations';
            protected $primaryKey = 'translations_id';
            protected $keyType = 'int';
            public $incrementing = true;
            public $timestamps = false;
    
            // ****** You need to put the entire namespace of the Model class
            public function country() {
                return $this->belongsTo('App\Country', 'translations_id', 'translations_id');
        }