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    Eloquent: Getting Started

    Introduction

    The Eloquent ORM included with Laravel provides a beautiful, simple ActiveRecord implementation for working with your database. Each database table has a corresponding "Model" which is used to interact with that table. Models allow you to query for data in your tables, as well as insert new records into the table.

    Before getting started, be sure to configure a database connection in config/database.php. For more information on configuring your database, check out the documentation.

    Defining Models

    To get started, let's create an Eloquent model. Models typically live in the app\Models directory, but you are free to place them anywhere that can be auto-loaded according to your composer.json file. All Eloquent models extend Illuminate\Database\Eloquent\Model class.

    The easiest way to create a model instance is using the make:model Artisan command:

    php artisan make:model Flight

    If you would like to generate a database migration when you generate the model, you may use the --migration or -m option:

    php artisan make:model Flight --migration
    
    php artisan make:model Flight -m

    You may generate various other types of classes when generating a model, such as factories, seeders, and controllers. In addition, these options may be combined to create multiple classes at once:

    php artisan make:model Flight --factory
    php artisan make:model Flight -f
    
    php artisan make:model Flight --seed
    php artisan make:model Flight -s
    
    php artisan make:model Flight --controller
    php artisan make:model Flight -c
    
    php artisan make:model Flight -mfsc

    Eloquent Model Conventions

    Now, let's look at an example Flight model, which we will use to retrieve and store information from our flights database table:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        //
    }

    Table Names

    Note that we did not tell Eloquent which table to use for our Flight model. By convention, the "snake case", plural name of the class will be used as the table name unless another name is explicitly specified. So, in this case, Eloquent will assume the Flight model stores records in the flights table, while an AirTrafficController model would store records in an air_traffic_controllers table.

    You can manually specify a table name by defining a table property on your model:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        /**
         * The table associated with the model.
         *
         * @var string
         */
        protected $table = 'my_flights';
    }

    Primary Keys

    Eloquent will also assume that each table has a primary key column named id. You may define a protected $primaryKey property to override this convention:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        /**
         * The primary key associated with the table.
         *
         * @var string
         */
        protected $primaryKey = 'flight_id';
    }

    In addition, Eloquent assumes that the primary key is an incrementing integer value, which means that by default the primary key will automatically be cast to an int. If you wish to use a non-incrementing or a non-numeric primary key you must set the public $incrementing property on your model to false:

    <?php
    
    class Flight extends Model
    {
        /**
         * Indicates if the IDs are auto-incrementing.
         *
         * @var bool
         */
        public $incrementing = false;
    }

    If your primary key is not an integer, you should set the protected $keyType property on your model to string:

    <?php
    
    class Flight extends Model
    {
        /**
         * The "type" of the auto-incrementing ID.
         *
         * @var string
         */
        protected $keyType = 'string';
    }

    Timestamps

    By default, Eloquent expects created_at and updated_at columns to exist on your tables. If you do not wish to have these columns automatically managed by Eloquent, set the $timestamps property on your model to false:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        /**
         * Indicates if the model should be timestamped.
         *
         * @var bool
         */
        public $timestamps = false;
    }

    If you need to customize the format of your timestamps, set the $dateFormat property on your model. This property determines how date attributes are stored in the database, as well as their format when the model is serialized to an array or JSON:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        /**
         * The storage format of the model's date columns.
         *
         * @var string
         */
        protected $dateFormat = 'U';
    }

    If you need to customize the names of the columns used to store the timestamps, you may set the CREATED_AT and UPDATED_AT constants in your model:

    <?php
    
    class Flight extends Model
    {
        const CREATED_AT = 'creation_date';
        const UPDATED_AT = 'last_update';
    }

    Database Connection

    By default, all Eloquent models will use the default database connection configured for your application. If you would like to specify a different connection for the model, use the $connection property:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        /**
         * The connection name for the model.
         *
         * @var string
         */
        protected $connection = 'connection-name';
    }

    Default Attribute Values

    If you would like to define the default values for some of your model's attributes, you may define an $attributes property on your model:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        /**
         * The model's default values for attributes.
         *
         * @var array
         */
        protected $attributes = [
            'delayed' => false,
        ];
    }

    Retrieving Models

    Once you have created a model and its associated database table, you are ready to start retrieving data from your database. Think of each Eloquent model as a powerful query builder allowing you to fluently query the database table associated with the model. For example:

    <?php
    
    $flights = App\Models\Flight::all();
    
    foreach ($flights as $flight) {
        echo $flight->name;
    }

    Adding Additional Constraints

    The Eloquent all method will return all of the results in the model's table. Since each Eloquent model serves as a query builder, you may also add constraints to queries, and then use the get method to retrieve the results:

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

    {tip} Since Eloquent models are query builders, you should review all of the methods available on the query builder. You may use any of these methods in your Eloquent queries.

    Refreshing Models

    You can refresh models using the fresh and refresh methods. The fresh method will re-retrieve the model from the database. The existing model instance will not be affected:

    $flight = App\Models\Flight::where('number', 'FR 900')->first();
    
    $freshFlight = $flight->fresh();

    The refresh method will re-hydrate the existing model using fresh data from the database. In addition, all of its loaded relationships will be refreshed as well:

    $flight = App\Models\Flight::where('number', 'FR 900')->first();
    
    $flight->number = 'FR 456';
    
    $flight->refresh();
    
    $flight->number; // "FR 900"

    Collections

    For Eloquent methods like all and get which retrieve multiple results, an instance of Illuminate\Database\Eloquent\Collection will be returned. The Collection class provides a variety of helpful methods for working with your Eloquent results:

    $flights = $flights->reject(function ($flight) {
        return $flight->cancelled;
    });

    You may also loop over the collection like an array:

    foreach ($flights as $flight) {
        echo $flight->name;
    }

    Chunking Results

    If you need to process thousands of Eloquent records, use the chunk command. The chunk method will retrieve a "chunk" of Eloquent models, feeding them to a given Closure for processing. Using the chunk method will conserve memory when working with large result sets:

    Flight::chunk(200, function ($flights) {
        foreach ($flights as $flight) {
            //
        }
    });

    The first argument passed to the method is the number of records you wish to receive per "chunk". The Closure passed as the second argument will be called for each chunk that is retrieved from the database. A database query will be executed to retrieve each chunk of records passed to the Closure.

    If you are filtering the results of the chunk method based on a column that you will also be updating while iterating over the results, you should use the chunkById method. Using the chunk method in these scenarios could lead to unexpected and inconsistent results:

    Flight::where('departed', true)->chunkById(200, function ($flights) {
        $flights->each->update(['departed' => false]);
    });

    Using Cursors

    The cursor method allows you to iterate through your database records using a cursor, which will only execute a single query. When processing large amounts of data, the cursor method may be used to greatly reduce your memory usage:

    foreach (Flight::where('foo', 'bar')->cursor() as $flight) {
        //
    }

    The cursor returns an Illuminate\Support\LazyCollection instance. Lazy collections allow you to use many of the collection methods available on typical Laravel collections while only loading a single model into memory at a time:

    $users = App\Models\User::cursor()->filter(function ($user) {
        return $user->id > 500;
    });
    
    foreach ($users as $user) {
        echo $user->id;
    }

    Advanced Subqueries

    Subquery Selects

    Eloquent also offers advanced subquery support, which allows you to pull information from related tables in a single query. For example, let's imagine that we have a table of flight destinations and a table of flights to destinations. The flights table contains an arrived_at column which indicates when the flight arrived at the destination.

    Using the subquery functionality available to the select and addSelect methods, we can select all of the destinations and the name of the flight that most recently arrived at that destination using a single query:

    use App\Models\Destination;
    use App\Models\Flight;
    
    return Destination::addSelect(['last_flight' => Flight::select('name')
        ->whereColumn('destination_id', 'destinations.id')
        ->orderBy('arrived_at', 'desc')
        ->limit(1)
    ])->get();

    Subquery Ordering

    In addition, the query builder's orderBy function supports subqueries. We may use this functionality to sort all destinations based on when the last flight arrived at that destination. Again, this may be done while executing a single query against the database:

    return Destination::orderByDesc(
        Flight::select('arrived_at')
            ->whereColumn('destination_id', 'destinations.id')
            ->orderBy('arrived_at', 'desc')
            ->limit(1)
    )->get();

    Retrieving Single Models / Aggregates

    In addition to retrieving all of the records for a given table, you may also retrieve single records using find, first, or firstWhere. Instead of returning a collection of models, these methods return a single model instance:

    // Retrieve a model by its primary key...
    $flight = App\Models\Flight::find(1);
    
    // Retrieve the first model matching the query constraints...
    $flight = App\Models\Flight::where('active', 1)->first();
    
    // Shorthand for retrieving the first model matching the query constraints...
    $flight = App\Models\Flight::firstWhere('active', 1);

    You may also call the find method with an array of primary keys, which will return a collection of the matching records:

    $flights = App\Models\Flight::find([1, 2, 3]);

    Sometimes you may wish to retrieve the first result of a query or perform some other action if no results are found. The firstOr method will return the first result that is found or, if no results are found, execute the given callback. The result of the callback will be considered the result of the firstOr method:

    $model = App\Models\Flight::where('legs', '>', 100)->firstOr(function () {
            // ...
    });

    The firstOr method also accepts an array of columns to retrieve:

    $model = App\Models\Flight::where('legs', '>', 100)
                ->firstOr(['id', 'legs'], function () {
                    // ...
                });

    Not Found Exceptions

    Sometimes you may wish to throw an exception if a model is not found. This is particularly useful in routes or controllers. The findOrFail and firstOrFail methods will retrieve the first result of the query; however, if no result is found, an Illuminate\Database\Eloquent\ModelNotFoundException will be thrown:

    $model = App\Models\Flight::findOrFail(1);
    
    $model = App\Models\Flight::where('legs', '>', 100)->firstOrFail();

    If the exception is not caught, a 404 HTTP response is automatically sent back to the user. It is not necessary to write explicit checks to return 404 responses when using these methods:

    Route::get('/api/flights/{id}', function ($id) {
        return App\Models\Flight::findOrFail($id);
    });

    Retrieving Aggregates

    You may also use the count, sum, max, and other aggregate methods provided by the query builder. These methods return the appropriate scalar value instead of a full model instance:

    $count = App\Models\Flight::where('active', 1)->count();
    
    $max = App\Models\Flight::where('active', 1)->max('price');

    Inserting & Updating Models

    Inserts

    To create a new record in the database, create a new model instance, set attributes on the model, then call the save method:

    <?php
    
    namespace App\Http\Controllers;
    
    use App\Http\Controllers\Controller;
    use App\Models\Flight;
    use Illuminate\Http\Request;
    
    class FlightController extends Controller
    {
        /**
         * Create a new flight instance.
         *
         * @param  Request  $request
         * @return Response
         */
        public function store(Request $request)
        {
            // Validate the request...
    
            $flight = new Flight;
    
            $flight->name = $request->name;
    
            $flight->save();
        }
    }

    In this example, we assign the name parameter from the incoming HTTP request to the name attribute of the App\Models\Flight model instance. When we call the save method, a record will be inserted into the database. The created_at and updated_at timestamps will automatically be set when the save method is called, so there is no need to set them manually.

    Updates

    The save method may also be used to update models that already exist in the database. To update a model, you should retrieve it, set any attributes you wish to update, and then call the save method. Again, the updated_at timestamp will automatically be updated, so there is no need to manually set its value:

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

    Mass Updates

    Updates can also be performed against any number of models that match a given query. In this example, all flights that are active and have a destination of San Diego will be marked as delayed:

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

    The update method expects an array of column and value pairs representing the columns that should be updated.

    {note} When issuing a mass update via Eloquent, the saving, saved, updating, and updated model events will not be fired for the updated models. This is because the models are never actually retrieved when issuing a mass update.

    Examining Attribute Changes

    Eloquent provides the isDirty, isClean, and wasChanged methods to examine the internal state of your model and determine how its attributes have changed from when they were originally loaded.

    The isDirty method determines if any attributes have been changed since the model was loaded. You may pass a specific attribute name to determine if a particular attribute is dirty. The isClean method is the opposite of isDirty and also accepts an optional attribute argument:

    $user = User::create([
        'first_name' => 'Taylor',
        'last_name' => 'Otwell',
        'title' => 'Developer',
    ]);
    
    $user->title = 'Painter';
    
    $user->isDirty(); // true
    $user->isDirty('title'); // true
    $user->isDirty('first_name'); // false
    
    $user->isClean(); // false
    $user->isClean('title'); // false
    $user->isClean('first_name'); // true
    
    $user->save();
    
    $user->isDirty(); // false
    $user->isClean(); // true

    The wasChanged method determines if any attributes were changed when the model was last saved within the current request cycle. You may also pass an attribute name to see if a particular attribute was changed:

    $user = User::create([
        'first_name' => 'Taylor',
        'last_name' => 'Otwell',
        'title' => 'Developer',
    ]);
    
    $user->title = 'Painter';
    $user->save();
    
    $user->wasChanged(); // true
    $user->wasChanged('title'); // true
    $user->wasChanged('first_name'); // false

    The getOriginal method returns an array containing the original attributes of the model regardless of any changes since the model was loaded. You may pass a specific attribute name to get the original value of a particular attribute:

    $user = User::find(1);
    
    $user->name; // John
    $user->email; // [email protected]
    
    $user->name = "Jack";
    $user->name; // Jack
    
    $user->getOriginal('name'); // John
    $user->getOriginal(); // Array of original attributes...

    Mass Assignment

    You may also use the create method to save a new model in a single line. The inserted model instance will be returned to you from the method. However, before doing so, you will need to specify either a fillable or guarded attribute on the model, as all Eloquent models protect against mass-assignment by default.

    A mass-assignment vulnerability occurs when a user passes an unexpected HTTP parameter through a request, and that parameter changes a column in your database you did not expect. For example, a malicious user might send an is_admin parameter through an HTTP request, which is then passed into your model's create method, allowing the user to escalate themselves to an administrator.

    So, to get started, you should define which model attributes you want to make mass assignable. You may do this using the $fillable property on the model. For example, let's make the name attribute of our Flight model mass assignable:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class Flight extends Model
    {
        /**
         * The attributes that are mass assignable.
         *
         * @var array
         */
        protected $fillable = ['name'];
    }

    Once we have made the attributes mass assignable, we can use the create method to insert a new record in the database. The create method returns the saved model instance:

    $flight = App\Models\Flight::create(['name' => 'Flight 10']);

    If you already have a model instance, you may use the fill method to populate it with an array of attributes:

    $flight->fill(['name' => 'Flight 22']);

    Mass Assignment & JSON Columns

    When assigning JSON columns, each column's mass-assignable key must be specified in your model's $fillable array. For security, Laravel does not support updating nested JSON attributes when using the guarded property:

    /**
     * The attributes that are mass assignable.
     *
     * @var array
     */
    $fillable = [
        'options->enabled',
    ];

    Allowing Mass Assignment

    If you would like to make all attributes mass assignable, you may define the $guarded property as an empty array:

    /**
     * The attributes that aren't mass assignable.
     *
     * @var array
     */
    protected $guarded = [];

    Other Creation Methods

    firstOrCreate/ firstOrNew

    There are two other methods you may use to create models by mass assigning attributes: firstOrCreate and firstOrNew. The firstOrCreate method will attempt to locate a database record using the given column / value pairs. If the model can not be found in the database, a record will be inserted with the attributes from the first parameter, along with those in the optional second parameter.

    The firstOrNew method, like firstOrCreate will attempt to locate a record in the database matching the given attributes. However, if a model is not found, a new model instance will be returned. Note that the model returned by firstOrNew has not yet been persisted to the database. You will need to call save manually to persist it:

    // Retrieve flight by name, or create it if it doesn't exist...
    $flight = App\Models\Flight::firstOrCreate(['name' => 'Flight 10']);
    
    // Retrieve flight by name, or create it with the name, delayed, and arrival_time attributes...
    $flight = App\Models\Flight::firstOrCreate(
        ['name' => 'Flight 10'],
        ['delayed' => 1, 'arrival_time' => '11:30']
    );
    
    // Retrieve by name, or instantiate...
    $flight = App\Models\Flight::firstOrNew(['name' => 'Flight 10']);
    
    // Retrieve by name, or instantiate with the name, delayed, and arrival_time attributes...
    $flight = App\Models\Flight::firstOrNew(
        ['name' => 'Flight 10'],
        ['delayed' => 1, 'arrival_time' => '11:30']
    );

    updateOrCreate

    You may also come across situations where you want to update an existing model or create a new model if none exists. Laravel provides an updateOrCreate method to do this in one step. Like the firstOrCreate method, updateOrCreate persists the model, so there's no need to call save():

    // If there's a flight from Oakland to San Diego, set the price to $99...
    // If no matching model exists, create one...
    $flight = App\Models\Flight::updateOrCreate(
        ['departure' => 'Oakland', 'destination' => 'San Diego'],
        ['price' => 99, 'discounted' => 1]
    );

    If you would like to perform multiple "upserts" in a single query, then you should use the upsert method instead. The method's first argument consists of the values to insert or update, while the second argument lists the column(s) that uniquely identify records within the associated table. The method's third and final argument is an array of the columns that should be updated if a matching record already exists in the database. The upsert method will automatically set the created_at and updated_at timestamps if timestamps are enabled on the model:

    App\Models\Flight::upsert([
        ['departure' => 'Oakland', 'destination' => 'San Diego', 'price' => 99],
        ['departure' => 'Chicago', 'destination' => 'New York', 'price' => 150]
    ], ['departure', 'destination'], ['price']);

    {note} All databases except SQL Server require the columns in the second argument of the upsert method to have a "primary" or "unique" index.

    Deleting Models

    To delete a model, call the delete method on a model instance:

    $flight = App\Models\Flight::find(1);
    
    $flight->delete();

    Deleting An Existing Model By Key

    In the example above, we are retrieving the model from the database before calling the delete method. However, if you know the primary key of the model, you may delete the model without explicitly retrieving it by calling the destroy method. In addition to a single primary key as its argument, the destroy method will accept multiple primary keys, an array of primary keys, or a collection of primary keys:

    App\Models\Flight::destroy(1);
    
    App\Models\Flight::destroy(1, 2, 3);
    
    App\Models\Flight::destroy([1, 2, 3]);
    
    App\Models\Flight::destroy(collect([1, 2, 3]));

    {note} The destroy method loads each model individually and calls the delete method on them so that the deleting and deleted events are fired.

    Deleting Models By Query

    You can also run a delete statement on a set of models. In this example, we will delete all flights that are marked as inactive. Like mass updates, mass deletes will not fire any model events for the models that are deleted:

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

    {note} When executing a mass delete statement via Eloquent, the deleting and deleted model events will not be fired for the deleted models. This is because the models are never actually retrieved when executing the delete statement.

    Soft Deleting

    In addition to actually removing records from your database, Eloquent can also "soft delete" models. When models are soft deleted, they are not actually removed from your database. Instead, a deleted_at attribute is set on the model and inserted into the database. If a model has a non-null deleted_at value, the model has been soft deleted. To enable soft deletes for a model, use the Illuminate\Database\Eloquent\SoftDeletes trait on the model:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    use Illuminate\Database\Eloquent\SoftDeletes;
    
    class Flight extends Model
    {
        use SoftDeletes;
    }

    {tip} The SoftDeletes trait will automatically cast the deleted_at attribute to a DateTime / Carbon instance for you.

    You should also add the deleted_at column to your database table. The Laravel schema builder contains a helper method to create this column:

    public function up()
    {
        Schema::table('flights', function (Blueprint $table) {
            $table->softDeletes();
        });
    }
    
    public function down()
    {
        Schema::table('flights', function (Blueprint $table) {
            $table->dropSoftDeletes();
        });
    }

    Now, when you call the delete method on the model, the deleted_at column will be set to the current date and time. And, when querying a model that uses soft deletes, the soft deleted models will automatically be excluded from all query results.

    To determine if a given model instance has been soft deleted, use the trashed method:

    if ($flight->trashed()) {
        //
    }

    Querying Soft Deleted Models

    Including Soft Deleted Models

    As noted above, soft deleted models will automatically be excluded from query results. However, you may force soft deleted models to appear in a result set using the withTrashed method on the query:

    $flights = App\Models\Flight::withTrashed()
                    ->where('account_id', 1)
                    ->get();

    The withTrashed method may also be used on a relationship query:

    $flight->history()->withTrashed()->get();

    Retrieving Only Soft Deleted Models

    The onlyTrashed method will retrieve only soft deleted models:

    $flights = App\Models\Flight::onlyTrashed()
                    ->where('airline_id', 1)
                    ->get();

    Restoring Soft Deleted Models

    Sometimes you may wish to "un-delete" a soft deleted model. To restore a soft deleted model into an active state, use the restore method on a model instance:

    $flight->restore();

    You may also use the restore method in a query to quickly restore multiple models. Again, like other "mass" operations, this will not fire any model events for the models that are restored:

    App\Models\Flight::withTrashed()
            ->where('airline_id', 1)
            ->restore();

    Like the withTrashed method, the restore method may also be used on relationships:

    $flight->history()->restore();

    Permanently Deleting Models

    Sometimes you may need to truly remove a model from your database. To permanently remove a soft deleted model from the database, use the forceDelete method:

    // Force deleting a single model instance...
    $flight->forceDelete();
    
    // Force deleting all related models...
    $flight->history()->forceDelete();

    Replicating Models

    You may create an unsaved copy of a model instance using the replicate method. This is particularly useful when you have model instances that share many of the same attributes:

    $shipping = App\Models\Address::create([
        'type' => 'shipping',
        'line_1' => '123 Example Street',
        'city' => 'Victorville',
        'state' => 'CA',
        'postcode' => '90001',
    ]);
    
    $billing = $shipping->replicate()->fill([
        'type' => 'billing'
    ]);
    
    $billing->save();

    Query Scopes

    Global Scopes

    Global scopes allow you to add constraints to all queries for a given model. Laravel's own soft delete functionality utilizes global scopes to only pull "non-deleted" models from the database. Writing your own global scopes can provide a convenient, easy way to make sure every query for a given model receives certain constraints.

    Writing Global Scopes

    Writing a global scope is simple. Define a class that implements the Illuminate\Database\Eloquent\Scope interface. This interface requires you to implement one method: apply. The apply method may add where constraints to the query as needed:

    <?php
    
    namespace App\Scopes;
    
    use Illuminate\Database\Eloquent\Builder;
    use Illuminate\Database\Eloquent\Model;
    use Illuminate\Database\Eloquent\Scope;
    
    class AgeScope implements Scope
    {
        /**
         * Apply the scope to a given Eloquent query builder.
         *
         * @param  \Illuminate\Database\Eloquent\Builder  $builder
         * @param  \Illuminate\Database\Eloquent\Model  $model
         * @return void
         */
        public function apply(Builder $builder, Model $model)
        {
            $builder->where('age', '>', 200);
        }
    }

    {tip} If your global scope is adding columns to the select clause of the query, you should use the addSelect method instead of select. This will prevent the unintentional replacement of the query's existing select clause.

    Applying Global Scopes

    To assign a global scope to a model, you should override a given model's booted method and use the addGlobalScope method:

    <?php
    
    namespace App\Models;
    
    use App\Scopes\AgeScope;
    use Illuminate\Database\Eloquent\Model;
    
    class User extends Model
    {
        /**
         * The "booted" method of the model.
         *
         * @return void
         */
        protected static function booted()
        {
            static::addGlobalScope(new AgeScope);
        }
    }

    After adding the scope, a query to User::all() will produce the following SQL:

    select * from `users` where `age` > 200

    Anonymous Global Scopes

    Eloquent also allows you to define global scopes using Closures, which is particularly useful for simple scopes that do not warrant a separate class:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Builder;
    use Illuminate\Database\Eloquent\Model;
    
    class User extends Model
    {
        /**
         * The "booted" method of the model.
         *
         * @return void
         */
        protected static function booted()
        {
            static::addGlobalScope('age', function (Builder $builder) {
                $builder->where('age', '>', 200);
            });
        }
    }

    Removing Global Scopes

    If you would like to remove a global scope for a given query, you may use the withoutGlobalScope method. The method accepts the class name of the global scope as its only argument:

    User::withoutGlobalScope(AgeScope::class)->get();

    Or, if you defined the global scope using a Closure:

    User::withoutGlobalScope('age')->get();

    If you would like to remove several or even all of the global scopes, you may use the withoutGlobalScopes method:

    // Remove all of the global scopes...
    User::withoutGlobalScopes()->get();
    
    // Remove some of the global scopes...
    User::withoutGlobalScopes([
        FirstScope::class, SecondScope::class
    ])->get();

    Local Scopes

    Local scopes allow you to define common sets of constraints that you may easily re-use throughout your application. For example, you may need to frequently retrieve all users that are considered "popular". To define a scope, prefix an Eloquent model method with scope.

    Scopes should always return a query builder instance:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class User extends Model
    {
        /**
         * Scope a query to only include popular users.
         *
         * @param  \Illuminate\Database\Eloquent\Builder  $query
         * @return \Illuminate\Database\Eloquent\Builder
         */
        public function scopePopular($query)
        {
            return $query->where('votes', '>', 100);
        }
    
        /**
         * Scope a query to only include active users.
         *
         * @param  \Illuminate\Database\Eloquent\Builder  $query
         * @return \Illuminate\Database\Eloquent\Builder
         */
        public function scopeActive($query)
        {
            return $query->where('active', 1);
        }
    }

    Utilizing A Local Scope

    Once the scope has been defined, you may call the scope methods when querying the model. However, you should not include the scope prefix when calling the method. You can even chain calls to various scopes, for example:

    $users = App\Models\User::popular()->active()->orderBy('created_at')->get();

    Combining multiple Eloquent model scopes via an or query operator may require the use of Closure callbacks:

    $users = App\Models\User::popular()->orWhere(function (Builder $query) {
        $query->active();
    })->get();

    However, since this can be cumbersome, Laravel provides a "higher order" orWhere method that allows you to fluently chain these scopes together without the use of Closures:

    $users = App\Models\User::popular()->orWhere->active()->get();

    Dynamic Scopes

    Sometimes you may wish to define a scope that accepts parameters. To get started, just add your additional parameters to your scope. Scope parameters should be defined after the $query parameter:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class User extends Model
    {
        /**
         * Scope a query to only include users of a given type.
         *
         * @param  \Illuminate\Database\Eloquent\Builder  $query
         * @param  mixed  $type
         * @return \Illuminate\Database\Eloquent\Builder
         */
        public function scopeOfType($query, $type)
        {
            return $query->where('type', $type);
        }
    }

    Now, you may pass the parameters when calling the scope:

    $users = App\Models\User::ofType('admin')->get();

    Comparing Models

    Sometimes you may need to determine if two models are the "same". The is method may be used to quickly verify two models have the same primary key, table, and database connection:

    if ($post->is($anotherPost)) {
        //
    }

    The is method is also available when using the belongsTo, hasOne, morphTo, and morphOne relationships. This method is particularly helpful when you would like to compare a related model without issuing a query to retrieve that model:

    if ($post->author()->is($user)) {
        //
    }

    Events

    Eloquent models fire several events, allowing you to hook into the following points in a model's lifecycle: retrieved, creating, created, updating, updated, saving, saved, deleting, deleted, restoring, restored, replicating. Events allow you to easily execute code each time a specific model class is saved or updated in the database. Each event receives the instance of the model through its constructor.

    The retrieved event will fire when an existing model is retrieved from the database. When a new model is saved for the first time, the creating and created events will fire. The updating / updated events will fire when an existing model is modified and the save method is called. The saving / saved events will fire when a model is created or updated.

    {note} When issuing a mass update or delete via Eloquent, the saved, updated, deleting, and deleted model events will not be fired for the affected models. This is because the models are never actually retrieved when issuing a mass update or delete.

    To get started, define a $dispatchesEvents property on your Eloquent model that maps various points of the Eloquent model's lifecycle to your own event classes:

    <?php
    
    namespace App\Models;
    
    use App\Events\UserDeleted;
    use App\Events\UserSaved;
    use Illuminate\Foundation\Auth\User as Authenticatable;
    
    class User extends Authenticatable
    {
        use Notifiable;
    
        /**
         * The event map for the model.
         *
         * @var array
         */
        protected $dispatchesEvents = [
            'saved' => UserSaved::class,
            'deleted' => UserDeleted::class,
        ];
    }

    After defining and mapping your Eloquent events, you may use event listeners to handle the events.

    Using Closures

    Instead of using custom event classes, you may register Closures that execute when various model events are fired. Typically, you should register these Closures in the booted method of your model:

    <?php
    
    namespace App\Models;
    
    use Illuminate\Database\Eloquent\Model;
    
    class User extends Model
    {
        /**
         * The "booted" method of the model.
         *
         * @return void
         */
        protected static function booted()
        {
            static::created(function ($user) {
                //
            });
        }
    }

    If needed, you may utilize queueable anonymous event listeners when registering model events. This will instruct Laravel to execute the model event listener using the queue:

    use function Illuminate\Events\queueable;
    
    static::created(queueable(function ($user) {
        //
    }));

    Observers

    Defining Observers

    If you are listening for many events on a given model, you may use observers to group all of your listeners into a single class. Observer classes have method names which reflect the Eloquent events you wish to listen for. Each of these methods receives the model as their only argument. The make:observer Artisan command is the easiest way to create a new observer class:

    php artisan make:observer UserObserver --model=User

    This command will place the new observer in your App/Observers directory. If this directory does not exist, Artisan will create it for you. Your fresh observer will look like the following:

    <?php
    
    namespace App\Observers;
    
    use App\Models\User;
    
    class UserObserver
    {
        /**
         * Handle the User "created" event.
         *
         * @param  \App\Models\User  $user
         * @return void
         */
        public function created(User $user)
        {
            //
        }
    
        /**
         * Handle the User "updated" event.
         *
         * @param  \App\Models\User  $user
         * @return void
         */
        public function updated(User $user)
        {
            //
        }
    
        /**
         * Handle the User "deleted" event.
         *
         * @param  \App\Models\User  $user
         * @return void
         */
        public function deleted(User $user)
        {
            //
        }
    
        /**
         * Handle the User "forceDeleted" event.
         *
         * @param  \App\Models\User  $user
         * @return void
         */
        public function forceDeleted(User $user)
        {
            //
        }
    }

    To register an observer, use the observe method on the model you wish to observe. You may register observers in the boot method of one of your service providers. In this example, we'll register the observer in the AppServiceProvider:

    <?php
    
    namespace App\Providers;
    
    use App\Observers\UserObserver;
    use App\Models\User;
    use Illuminate\Support\ServiceProvider;
    
    class AppServiceProvider extends ServiceProvider
    {
        /**
         * Register any application services.
         *
         * @return void
         */
        public function register()
        {
            //
        }
    
        /**
         * Bootstrap any application services.
         *
         * @return void
         */
        public function boot()
        {
            User::observe(UserObserver::class);
        }
    }

    Muting Events

    You may occasionally wish to temporarily "mute" all events fired by a model. You may achieve this using the withoutEvents method. The withoutEvents method accepts a Closure as its only argument. Any code executed within this Closure will not fire model events. For example, the following will fetch and delete an App\Models\User instance without firing any model events. Any value returned by the given Closure will be returned by the withoutEvents method:

    use App\Models\User;
    
    $user = User::withoutEvents(function () use () {
        User::findOrFail(1)->delete();
    
        return User::find(2);
    });

    Saving A Single Model Without Events

    Sometimes you may wish to "save" a given model without raising any events. You may accomplish this using the saveQuietly method:

    $user = User::findOrFail(1);
    
    $user->name = 'Victoria Faith';
    
    $user->saveQuietly();
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