Laravel Eloquent ORM: Defining Models, Queries, and Data Operations

Laravel's Eloquent ORM provides a clean ActiveRecord implementation for interacting with databases. Each table has a corresponding model class that extends Illuminate\Database\Eloquent\Model . Before starting, ensure the database connection is configured in config/database.php .

Defining Models

Generate a model using the Artisan command php artisan make:model User . To also create a migration, add the --migration or -m option.

php artisan make:model User

php artisan make:model User --migration

Eloquent Model Conventions

By default, Eloquent assumes the table name is the snake‑cased plural of the model class (e.g., Flight maps to flights ). Override this by defining a protected $table = 'my_flights'; property.

class Flight extends Model {
    /**
     * The table associated with the model.
     *
     * @var string
     */
    protected $table = 'my_flights';
}

The primary key defaults to id . Change it with a protected $primaryKey property, and adjust its type or incrementing behavior as needed.

class Flight extends Model {
    protected $primaryKey = 'flight_id';
    public $incrementing = false;
    protected $keyType = 'string';
}

Timestamps

Eloquent automatically maintains created_at and updated_at . Disable them by setting public $timestamps = false; or customize the format with protected $dateFormat = 'U'; . Custom column names can be defined via const CREATED_AT = 'creation_date'; and const UPDATED_AT = 'last_update'; .

class Flight extends Model {
    public $timestamps = false;
    protected $dateFormat = 'U';
    const CREATED_AT = 'creation_date';
    const UPDATED_AT = 'last_update';
}

Retrieving Models

Use static methods like all() , where() , get() , find() , and first() to fetch records. Chain query constraints and retrieve collections via Illuminate\Database\Eloquent\Collection .

$flights = App\Flight::all();
$flight = App\Flight::find(1);
$flight = App\Flight::where('active', 1)->first();

Adding Constraints

Apply additional query constraints before calling get() :

$flights = App\Flight::where('active', 1)
    ->orderBy('name', 'desc')
    ->take(10)
    ->get();

Collections

Collections provide methods like reject() , each() , and support array‑style iteration.

$flights = $flights->reject(function ($flight) {
    return $flight->cancelled;
});
foreach ($flights as $flight) {
    echo $flight->name;
}

Chunking Results

Process large data sets efficiently with chunk() or cursor() to reduce memory usage.

Flight::chunk(200, function ($flights) {
    foreach ($flights as $flight) {
        // process each flight
    }
});
foreach (Flight::where('foo', 'bar')->cursor() as $flight) {
    // iterate with a cursor
}

Inserting & Updating Models

Insert

Create a model instance, set attributes, and call save() :

use App\Flight;
$flight = new Flight;
$flight->name = $request->name;
$flight->save();

Update

Retrieve the model, modify attributes, and call save() again. Timestamps are updated automatically.

$flight = App\Flight::find(1);
$flight->name = 'New Flight Name';
$flight->save();

Bulk Update

Update multiple rows without retrieving models:

App\Flight::where('active', 1)
    ->where('destination', 'San Diego')
    ->update(['delayed' => 1]);

Mass Assignment

Define $fillable or $guarded on the model to allow create() or fill() with an attribute array.

class Flight extends Model {
    protected $fillable = ['name'];
}
$flight = Flight::create(['name' => 'Flight 10']);
$flight->fill(['name' => 'Flight 22']);

Guarded Attributes

Use $guarded as a blacklist, or an empty array to allow all attributes.

protected $guarded = ['price'];
protected $guarded = [];

Other Creation Methods

firstOrCreate and firstOrNew attempt to find a record and create one if it does not exist. updateOrCreate updates an existing record or creates a new one.

$flight = Flight::firstOrCreate(['name' => 'Flight 10']);
$flight = Flight::firstOrNew(['name' => 'Flight 10']);
$flight->save();
$flight = Flight::updateOrCreate(['departure' => 'Oakland', 'destination' => 'San Diego'], ['price' => 99]);

Deleting Models

Call delete() on an instance, or use destroy() with primary keys to delete without retrieval.

$flight = App\Flight::find(1);
$flight->delete();
App\Flight::destroy(1);
App\Flight::destroy([1, 2, 3]);

Bulk Delete

Delete rows matching a condition; model events are not fired.

$deletedRows = App\Flight::where('active', 0)->delete();

Soft Deletes

Use the SoftDeletes trait and a deleted_at column to hide records instead of removing them permanently.

use Illuminate\Database\Eloquent\SoftDeletes;
class Flight extends Model {
    use SoftDeletes;
    protected $dates = ['deleted_at'];
}

Query helpers: withTrashed() , onlyTrashed() , and restore() . Permanently delete with forceDelete() .

$flights = Flight::withTrashed()->where('account_id', 1)->get();
$flight->restore();
Flight::withTrashed()->where('airline_id', 1)->restore();
$flight->forceDelete();

Query Scopes

Global Scopes

Implement Illuminate\Database\Eloquent\Scope and add it in the model's boot() method with addGlobalScope() . Use withoutGlobalScope() or withoutGlobalScopes() to remove them.

class AgeScope implements Scope {
    public function apply(Builder $builder, Model $model) {
        $builder->where('age', '>', 200);
    }
}
class User extends Model {
    protected static function boot() {
        parent::boot();
        static::addGlobalScope(new AgeScope);
    }
}
User::withoutGlobalScope(AgeScope::class)->get();
User::withoutGlobalScope('age')->get();
User::withoutGlobalScopes()->get();

Local Scopes

Define reusable query fragments with methods prefixed by scope . They can be chained and accept parameters.

class User extends Model {
    public function scopePopular($query) {
        return $query->where('votes', '>', 100);
    }
    public function scopeActive($query) {
        return $query->where('active', 1);
    }
    public function scopeOfType($query, $type) {
        return $query->where('type', $type);
    }
}
$users = User::popular()->active()->orderBy('created_at')->get();
$admins = User::ofType('admin')->get();

Events

Eloquent fires events such as retrieved , creating , created , updating , updated , saving , saved , deleting , deleted , restoring , and restored . Map them to custom event classes via the model's $dispatchesEvents property.

class User extends Authenticatable {
    protected $dispatchesEvents = [
        'saved'   => UserSaved::class,
        'deleted' => UserDeleted::class,
    ];
}

Observers

Group multiple event listeners in an observer class with methods named after the events. Register the observer in a service provider's boot() method using Model::observe(Observer::class) .

class UserObserver {
    public function created(User $user) {
        // handle created event
    }
    public function deleting(User $user) {
        // handle deleting event
    }
}
// In AppServiceProvider
User::observe(UserObserver::class);