Top 70 Laravel Interview Questions

I am going to share basic Laravel Interview Questions with Answers. It's really helpful for Laravel fresher and Laravel experienced candidate for getting the right Laravel job.
.

Top 70 Laravel Interview Questions

Define @include

@include is used to load more than one template view files. It helps you to include view within another view. User can also load multiple files in one view.

Define hashing in Laravel

It is the method of converting text into a key that shows the original text. Laravel uses the Hash facade to store the password securely in a hashed manner.

Does Laravel support caching?

Yes, Laravel supports popular caching backends like Memcached and Redis.
By default, Laravel is configured to use the file cache driver, which stores the serialized, cached objects in the file system.For large projects, it is recommended to use Memcached or Redis.

Explain Auth

It is a method of identifying user login credential with a password. In Laravel it can be managed with a session which takes two parameters 1) username and 2) password.

Explain Facades in Laravel?

Laravel Facades provides a static-like interface to classes that are available in the application’s service container. Laravel self-ships with many facades which provide access to almost all features of Laravel ’s. Laravel facades serve as “static proxies” to underlying classes in the service container and provide benefits of a terse, expressive syntax while maintaining more testability and flexibility than traditional static methods of classes. All of Laravel’s facades are defined in the Illuminate\Support\Facades namespace. You can easily access a facade like so:
use Illuminate\Support\Facades\Cache;
Route::get('/cache', function () {
    return Cache::get('key');
});

Explain faker in Laravel

It is a type of module or packages which are used to create fake data. This data can be used for testing purpose.
It is can also be used to generate: 1) Numbers, 2) Addresses, 3) DateTime, 4) Payments, and 5) Lorem text.

Explain fluent query builder in Laravel

It is a database query builder that provides convenient, faster interface to create and run database queries.

Explain important directories used in a common Laravel application.

Directories used in a common Laravel application are:

• App/: This is a source folder where our application code lives. All controllers, policies, and models are inside this folder.
• Config/: Holds the app's configuration files. These are usually not modified directly but instead, rely on the values set up in the .env (environment) file at the root of the app.
• Database/: Houses the database files, including migrations, seeds, and test factories.
• Public/: Publicly accessible folder holding compiled assets and of course an index.php file.

Explain Inversion of Control, how to implement it

Inversion of control is a design pattern that is used for decoupling components and layers of a system. Inversion of control(IOC) is implemented through injecting dependencies into a component when it is constructed.

Explain Laravel echo

It is a JavaScript library that makes possible to subscribe and listen to channels Laravel events. You can use NPM package manager to install echo.

Explain Laravel’s service container?

One of the most powerful features of Laravel is its Service Container. It is a powerful tool for resolving class dependencies and performing dependency injection in Laravel.
Dependency injection is a fancy phrase that essentially means class dependencies are “injected” into the class via the constructor or, in some cases, “setter” methods.

Explain Loggin in Laravel

It is a technique in which system log generated errors. Loggin is helpful to increase the reliability of the system. Laravel supports various logging modes like syslog, daily, single, and error log modes.

Explain the concept of contracts in Laravel

They are set of interfaces of Laravel framework. These contracts provide core services. Contracts defined in Laravel include corresponding implementation of framework.

Explain the concept of cookies

Cookies are small file sent from a particular website and stored on PC by user's browser while the user is browsing.

Explain the concept of encryption and decryption in Laravel.

It is a process of transforming any message using some algorithms in such way that the third user cannot read information. Encryption is quite helpful to protect your sensitive information from an intruder.
Encryption is performed using a Cryptography process. The message which is to be encrypted called as a plain message. The message obtained after the encryption is referred to as cipher message. When you convert cipher text to plain text or message, this process is called as decryption.

Explain the server requirements for Laravel 6?

• PHP version >= 7.2.0
• JSON PHP Extension
• BCMath PHP Extension
• Ctype PHP Extension
• Mbstring PHP Extension
• XML PHP Extension.
• Tokenizer PHP Extension
• OpenSSL PHP Extension
• PDO PHP Extension

Explain to listeners

Listeners are used to handling events and exceptions. The most common listener in Laravel for login event is LoginListener.

Explain web.php route

Web.php is the public-facing "browser" based route. This route is the most common and is what gets hit by the web browser. They run through the web middleware group and also contain facilities for CSRF protection (which helps defend against form-based malicious attacks and hacks) and generally contain a degree of "state" (by this I mean they utilize sessions).

How can you reduce memory usage in Laravel?

While processing a large amount of data, you can use the cursor method in order to reduce memory usage.

How to change your default database type in Laravel?

Please update 'default' => env('DB_CONNECTION', 'mysql'), in config/database.php. Update MySQL as a database whatever you want.

How to check request is ajax or not?

In Laravel, we can use $request->ajax() method to check request is ajax or not.
Example:
public function saveData(Request $request)
{
    if($request->ajax()){
        return "Request is of Ajax Type";
    }
    return "Request is of Http type";
}

How to clear complete cache in Laravel?

Please run below artisan commands step wise step.

• php artisan config:clear
• php artisan cache:clear
• composer dump-autoload
• php artisan view:clear
• php artisan route:clear

How to enable or disable maintenance mode in Laravel?

We have to use the following artisan commands to enable/disable maintenance mode.
Enable maintenance mode
php artisan down
Disable maintenance mode
php artisan up

How to enable query log in laravel?

Our first step should be
DB::connection()->enableQueryLog();
After our query, it should be placed
$querieslog = DB::getQueryLog();
After that, it should be placed
dd($querieslog)
Example                       
DB::connection()->enableQueryLog();
$result = User:where(['status' => 1])->get();
$log = DB::getQueryLog();
dd($log);

How to exclude a route with parameters from CSRF verification?

You can cut out a route from CSRF verification by using adding the route to $except property at VerifyCsrfToken middleware.
Example
protected $except = [
     'admin/api/interview/*'
];

How to get last inserted id using laravel query?

In case you are using save()
$blog = new Blog;
$blog->title = ‘Best Interview Questions’;
$blog->save()
// Now you can use (after save() function we can use like this)
$blog->id // It will display last inserted id
In case you are using insertGetId()
$insertGetId = DB::table(‘blogs’)->insertGetId([‘title’ => ‘Best Interview Questions’]);

How to get user’s ip address in laravel?

You can use request()->ip()
You can also use : Request::ip() but in this case, we have to call namespace like this: Use Illuminate\Http\Request

How to override a Laravel model's default table name?

We have to pass protected $table = 'guru_interview'; in your respective Model
This is one of the most asked laravel interview questions.
You can also read: Mysql Interview Questions
Example                         
namespace App;
use Illuminate\Database\Eloquent\Model;
class User extends Model
{
    protected $table = 'guru_interview';
}

How to redirect form controller to view file in laravel?

We can use
return redirect('/')->withErrors('Something went wrong!');
return redirect('/')->with('error', 'Something went wrong!');
return redirect('/')->route('product');

How to remove a complied class file?

Use clear-compiled command to remove the compiled class file.

How to rollback last migration?

Use need to use artisan command to rollback the last migration.

How to upload files in laravel?

We have to call Facades in our controller file with this :
use Illuminate\Support\Facades\Storage;
Example                                                 
if($request->hasFile(file_name')) {
    $file = Storage::putFile('YOUR FOLDER PATH', $request->file('file_name'));
}

How to use aggregate functions in Laravel?

Laravel provides a variety of aggregate functions such as max, min, count,avg, and sum. We can call any of these functions after constructing our query.
$users = DB::table(‘admin’)->count();
$maxComment = DB::table(‘blogs’)->max('comments');

How to use cookies in laravel?

How to set Cookie
To set cookie value, we have to use Cookie::put('key', 'value');
How to get Cookie
To get cookie Value we have to use Cookie::get('key');
How to delete or remove Cookie
To remove cookie Value we have to use Cookie::forget('key')
How to check Cookie
To Check cookie is exists or not, we have to use Cache::has('key')

How to use custom table in Laravel Modal?

You can use the custom table in Laravel by overriding protected $table property of Eloquent.
Below is sample uses
class User extends Eloquent{
    protected $table="my_user_table";
}

How to use skip() and take() in Laravel Query?

We can use skip() and take() both methods to limit the number of results in the query. skip() is used to skip the number of results and take() is used to get the number of result from the query.
Example
$posts = DB::table('blog')->skip(5)->take(10)->get();

How to use update query in Laravel?

With the help of update() function, we can update our data in the database according to the condition.
Example                                      
Blog::where(['id' => $id])->update([
   'title' => 'Best Interview Questions',
   'content' => 'Best Interview Questions'
]); 
//OR
DB::table("blogs")->where(['id' => $id])->update([
    'title' => 'Best Interview Questions',
    'content' => 'Best Interview Questions'
]);

How to use updateOrInsert() method in Laravel Query?

updateOrInsert() method is used to update an existing record in the database if matching the condition or create if no matching record exists.
Its return type is Boolean.
Syntax
DB::table(‘blogs’)->updateOrInsert([Conditons],[fields with value]);
Example
DB::table(‘blogs’)->updateOrInsert(
     ['email' => 'info@bestinterviewquestion.com', 'title' => 'Best Interview Questions'],
     ['content' => 'Test Content']
);

In which folder robot.txt is placed?

Robot.txt file is placed in Public directory.

Laravel is developed By

Taylor Otwell

List basic concepts in Laravel?

Following are basic concepts used in Laravel:

• Routing
• Eloquent ORM
• Middleware
• Security
• Caching
• Blade Templating

List some default packages provided by Laravel 5.6?

Below are a list of some official/ default packages provided by Laravel

• Cashier
• Envoy
• Passport
• Scout
• Socialite
• Horizon

List some features of laravel 5.0?

Laravel 5.0 features

• Inbuilt CRSF (cross-site request forgery ) Protection.
• Inbuilt paginations
• Reverse Routing
• Query builder
• Route caching
• Database Migration
• IOC (Inverse of Control) Container Or service container.

List types of relationships available in Laravel Eloquent?

Below are types of relationships supported by Laravel Eloquent ORM.

• One To One
• One To Many
• One To Many (Inverse)
• Many To Many
• Has Many Through
• Polymorphic Relations
• Many To Many Polymorphic Relations

Name databases supported by Laravel

Laravel supports the following databases:

• PostgreSQL
• SQL Server
• SQLite
• MySQL

State the difference between authentication and authorization

Authentication means confirming user identities through credentials, while authorization refers to gathering access to the system.

What are common HTTP error codes?

The most common HTTP error codes are:

• Error 404 – Displays when Page is not found.
• Error- 401 – Displays when an error is not authorized

What are policies classes?

Policies classes include authorization logic of Laravel application. These classes are used for a particular model or resource.

What are service providers in Laravel?

Service Providers are a central place where all laravel application is bootstrapped. Your application as well all Laravel core services are also bootstrapped by service providers.
All service providers extend the Illuminate\Support\ServiceProvider class. Most service providers contain a register and a boot method. Within the register method, you should only bind things into the service container. You should never attempt to register any event listeners, routes, or any other piece of functionality within the register method.

What are the advantages of Queue?

• In Laravel, Queues are very useful for taking jobs, pieces of asynchronous work, and sending them to be performed by other processes and this is useful when making time-consuming API calls that we don’t want to make your users wait for before being served their next page.
• Another advantage of using queues is that you don’t want to work the lines on the same server as your application. If your jobs involve intensive computations, then you don’t want to take risk those jobs taking down or slowing your web server.

What are the advantages of using Laravel?

Here are important benefits of Laravel:

• Laravel has blade template engine to create dynamic layouts and increase compiling tasks.
• Reuse code without any hassle.
• Laravel provides you to enforce constraints between multiple DBM objects by using an advanced query builder mechanism.
• The framework has an auto-loading feature, so you don't do manual maintenance and inclusion paths
• The framework helps you to make new tools by using LOC container.
• Laravel offers a version control system that helps with simplified management of migrations.

What are the difference between insert() and insertGetId() in laravel?

Inserts(): This method is used for insert records into the database table. No need the “id” should be autoincremented or not in the table.
Example
DB::table('bestinterviewquestion_users')->insert(
    ['title' => 'Best Interview Questions', 'email' => ‘info@bestinterviewquestion.com’]
);
It will return true or false.
insertGetId(): This method is also used for insert records into the database table. This method is used in the case when an id field of the table is auto incrementing.
It returns the id of current inserted records.
Example
$id = DB::table('bestinterviewquestion_users')->insert(
    ['title' => 'Best Interview Questions', 'email' => ‘info@bestinterviewquestion.com’]
);

What are the difference between laravel 4 and 5?

There are sizable differences between laravel 4 and laravel 5 concerning LTS, features, file structures, etc.
Laravel four used to be the one who delivered large reputation to the Laravel framework, however this version no longer up to date anymore, and it also lacks a lot of functions released in Laravel 5.

• Laravel 4 released May 2013 however Laravel 5 released in February 2015.
• Laravel 5 has LTS Supports. It capability the LTS version stands for Long Term Support. It implies that bugfixes for that model will be provided for two years, till the next LTS version.
• A new listing app/Providers replaces the app/start archives from preceding versions of Laravel 4.x.
• Laravel 5 offers a Socialite bundle which is an optional, Laravel 5.0+ well-matched package that provides painless authentication with OAuth providers.
• The favoured dd helper function, which dumps variable debug information, has been upgraded to use the incredible Symfony VarDumper

In distinction to Laravel four to 5 version differences, which is huge, 5.x and 5.y variations are now not that different. Some features added, some updated/removed in laravel 5, but the core structure stays the same.

What are views?

Views contain the HTML provided by our application and separate our controller or application logic from our presentation logic. These are stored in the resources/views directory.
<html>
    <body>
        <h1>Best Interview Question<h1>
    </body>
</html>

What is a Controller?

A controller is the "C" in the "MVC" (Model-View-Controller) architecture, which is what Laravel is based on.

What is Ajax in Laravel?

Ajax stands for Asynchronous JavaScript and XML is a web development technique that is used to create asynchronous Web applications. In Laravel, response() and json() functions are used to create asynchronous web applications.

What is Blade laravel?

Blade is very simple and powerful templating engine that is provided with Laravel. Laravel uses "Blade Template Engine".

What is dd() in laravel?

It is a helper function which is used to dump a variable's contents to the browser and stop the further script execution. It stands for Dump and Die.
Example
dd($array);

What is dependency injection in Laravel?

In software engineering, dependency injection is a technique whereby one object supplies the dependencies of another object. A dependency is an object that can be used (a service). An injection is the passing of a dependency to a dependent object (a client) that would use it. The service is made part of the client’s state. Passing the service to the client, rather than allowing a client to build or find the service, is the fundamental requirement of the pattern.

What is eager loading in Laravel?

Eager loading is used when we have to fetch some useful data along with the data which we want from the database. We can eager load in laravel using the load() and with() commands.

What is Facade and how it can be used in Laravel?

In Laravel, Facades offer a static interface to classes available inside the application's service container. They serve as static proxies for underlying classes present in the service container, offering benefit of expressive syntax while maintaining more flexibility and testability than other available traditional static methods.
All the facades are defined in the namespace Illuminate\Support\Facades for easy accessibility and usability.
Example
use Illuminate\Support\Facades\Cache;
Route::get('/cache', function () {
     return Cache::get('laravel_interview_questions');
});

What is faker in Laravel?

Faker is a type of module or packages which are used to create fake data for testing purposes. It can be used to produce all sorts of data.
It is used to generate the given data types.

• Lorem text
• Numbers
• Person i.e. titles, names, gender, etc.
• Addresses
• DateTime
• Phone numbers
• Internet i.e. domains, URLs, emails etc.
• Payments
• Colour, Files, Images
• UUID, Barcodes, etc

What is fillable in laravel model?

It is an array which contains all those fields of table which can be created a directly new record in your database table.
Example           
class User extends Model {
    protected $fillable = ['firstname', 'lastname', 'phone'];
}

What is Guarded Attribute in a Model?

It is the reverse of fillable. When a guarded specifies which fields are not mass assignable.
Example 
class Product extends Model {
     protected $guarded = ['product_type'];
}

What is Laravel API rate limit?

It is a feature of Laravel. It provides handle throttling. Rate limiting helps Laravel developers to develop a secure application and prevent DOS attacks.

What is Laravel?

Laravel is a free open source "PHP framework" based on the MVC design pattern.
It is created by Taylor Otwell. Laravel provides expressive and elegant syntax that helps in creating a wonderful web application easily and quickly.

What is Lumen?

Lumen is PHP micro-framework that built on Laravel’s top components. It is created by Taylor Otwell. It is a perfect option for building Laravel based micro-services and fast REST API. It’s one of the fastest micro-frameworks available.

What is named route?

Name route is a method generating routing path. The chaining of these routes can be selected by applying the name method onto the description of route.

What is namespace in Laravel?

A namespace allows a user to group the functions, classes, and constants under a specific name.

What is PHP artisan. List out some artisan commands?

PHP artisan is the command line interface/tool included with Laravel. It provides a number of helpful commands that can help you while you build your application easily. Here is the list of some artisan command:-

• php artisan list
• php artisan help
• php artisan tinker
• php artisan make
• php artisan make model model_name
• php artisan make controller controller_name