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100 Top Interview Laravel Question for Fresher and Experience

100 Laravel Framework Interview Question

1) Describe Laravel?

Laravel is MVC(Model View Controller) architecture based open Source php Framework developed by Taylor Otwell. Latest version of Laravel Framework is 7.0 which got released on March 3rd.

Laravel 1st version got released on 9th June 2011.

2) What are the Laravel Framework Feature ?

Top Feature of laravel Framework is below.

CRSF (cross-site request forgery )
Eloquent ORM
Laravel paginations
Database Seeding
Reverse Routing
Query builder
Route caching
Database Migration
Unit Testing
IOC (Inverse of Control) Container.
Job middleware
Lazy collections

3) Define Laravel Eloquent ORM ?

Laravel Eloquent feature is object Oriented paradigm approach of database communication. In Eloquent we create Model for each Table in the database, which set the communication (Fetching, Inserting, Deleting, Modifying the Record ) with database. It represent Database Table as a Class.

Laravel Eloquent ORM With Example Read More

4) What is Soft Delete? How to use it in Laravel Model?

Soft Delete is feature of laravel framework which helps when model is soft deleted. In this scenario the data record is not deleted form the database table instead deleted_at timestamp is maintained.

5) Define Laravel Query Builder ?

Query Builder in Larevel is a Package through which we create and run database query Quickly to run the application smoothly. Query Bulider Use PHP Data Object (PDO) where we dont have to worry about the SQL Injection. It can perform all Database Operation such as CRUD, DB Connection, Aggregate Function etc.

Laravel Query Builder With Example Read More

6) Explain Middleware Concept in Laravel?

Laravel Middleware provide a filter as well as it act as interface or Middle-Man between HTTP request and response which access the application. Middleware is a way to filter all the bad or Forgery request which try to access your Application.

Laravel Middleware Type

Global Middleware
Route Middleware

Laravel Middleware With Example Read More

7) Define Aggregate Function ? What are the aggregate function available in Lravel Query Builder?

In Aggregate Function, Database Table Rows are grouped together based on certain Criteria to get specific summary value. Laravel Provide various aggregate function which we can use in our query, list is below for your reference.

count() function
max() function
min() function
sum() function
avg() function

Note: All Aggregate function defined above ignore NULL Value except Count() function.

8) Explain Laravel Migration? Write the Artisan Command for Laravel Migration ?

Laravel Database Migration is way through which we build and maintain the Database Schema. Migration is Version Control of Your DB, which will allow Developer team easily to modify and share the DB Schema.

Laravel DB Migration provide the facility for those who is not able and poor in maintaining, updating Database.

Migration In Laravel contain by default Two method up() method is called when a DB is modified or changed. Whereas, the DB Migration down() method is called when DB is reverted back.

Artisan Command for Laravel migration. php artisan migrate

9) Describe Laravel Reverse Routing ?

Laravel reverse Routing is one of the Awesome Route Feature. Reverse Routing is process of generating the URL based on the Route Deceleration. Reverse Routing sets a relationship between links and web routes.

Consider below route declared as Example (consider your Website as www.abc.com)

 Route::get('user-login','UserController@userLogin');

{ { url( '/usre-login' ) } }

$url-link = URL::route('usre-login');

$redirect-link = Redirect::route('usre-login');

Above three will generate the URL which is below as a example :

URL : www.abc.com/user-login

Now reverse routing is process to generate the url based on Name or other parameter.

{{ HTML :: link_to_action( ' UserController@userLogin ' ) }}

This above reverse routing will also generate or point the same URL www.abc.com/user-login .

10) What is Artisan ? List some Common Php Artisan command?

Artisan is command line Interface tool which help in laravel Application Building. To Kmow all this List of Artisan command, Use the below Artisan command.

php artisan list

List of Common Artisan Command for hassle free Laravel application Development is below:-

php artisan list
php artisan make:controller controller-name
php artisan make:model model-name
php artisan migrate
php artisan make:middleware middleware-name
php artisan tinker

11) Define Controller ?

Controller handle all the HTTP Request logically and divert the Web Traffic to View and Model. It Contain all the Http Handling Logic within Single Class. Artisan Command to create the Controller is below for your Reference.

php artisan make:controller controllerName

Controller is C of MVC(Model View Controller).

12) List out some Laravel Official Packages?

Laravel Packages list is below for your reference.

Dusk Package
Envoy Package
Horizon Package
Cashier Package
Passport Package
Scout Package
Socialite Package
Telescope Package

13) What is the difference between find() and where() method in laravel?

The Major Difference between them is find() method always use Primary Key to filter the table record, whereas where() method uses any table column to filter the table record set.

find() method will return the single table row from the database. where() method return multiple record based on the condition.

14) What is Named Route in Laravel ?

Named Route is a friendly name given to the route the reference. We can use Named rout to specify the particular Route as well as to generate the URL / to redirect to specific URL.

Route::post('profile-data/save', 'ProfileController@saveProfile')->name('profileData');

You must keep the route name always unique. Generating / Redirecting Url for Names Route is below for your reference.

$url = route('profile');

return redirect()->route('profile');

With Name Route we can pass the second or third parameter as a argument.

Route::post('profile-data/{id}', 'ProfileController@updateProfile')->name('profileData');

To pass the parameter as argument in the named Route code is below for your reference.

$url = route('profile', ['id'=>1 ]);

If we pass the additional parameter in the array, that will be automatically added in the URL generated query String. Below is the example for reference.

$url = route('profile-data/{id}', ['id' => 1, 'rollno' => '1004']);

URL String generated is below /1/profile?rollno=1004

15) Define Laravel Validation?

Laravel Validation is the way through which we can verify and filter the data coming to the Application database. We can have clean and validated data in the database coming with HTTP with powerful validation rule.

As we know that we store the data in the Database using form. As we must not fill our database with junk and invalid data, we do form validation in client Side as well as server side. The validation purpose is to get the exact data what is required for application.

You can use validate method for data filteration.

$validatedData = $request->validate([
            'FULL_NAME' => 'required|max:25',
            'mobile' => 'required|digits:10|unique:valid_table,mobile',
            'email' => 'required|email|max:255',
        ]);

You can use Validation make() method to create manual validator.

$validator = Validator::make($request->all(), [
            'first_name' => 'required|max:255',
            'mobile' => 'required|digits:10',
        ])->validate();

16) Define Route::fallback method with Example?

Route::fallback method is another feature of Laravel Routing in which we handle the HTTP request which do not match with our route list. By default laravel render the 404 not found page using exception handler. Now laravel fallback method you can define and redirect to the view which will get execute if not HTTP request matches.

You must always define the Route::fallback method at the last of route file. Below is the code for your reference.

Route::fallback(function() {
    return 'You have landed on wrong url. ';
});

Laravel Eloquent ORM Query and Model Feature

Laravel Eloquent feature is object Oriented paradigm approach of database communication. In Eloquent we create Model for each Table in the database, which set the communication (Fetching, Inserting, Deleting, Modifying the Record ) with database.

You can create the Model with Migration or without migration with the help of Artisan Command. We can use -m or --migration after the artisan command to create the Model with Migration. Below code is the Example.

Eloquent Model with Database Migration

Create Model with migration using Artisan Command. Below is the command to create Model with migration.

php artisan make:model model-Name -m (-m is for migration )

php artisan make:model model-Name --migration (--migration is for migration )

This above two Artisan Command will create Table migration file in your databaese / migration directory which you can modify further.

Create Model without Migration. Below is the Artisan command to create Model.

php artisan make:model model-Name

Lets Take Example, We will create Model Named with CategoryMaster

php artisan make:model CategoryMaster -m

This above Artisan Command will create the Model named with CategoryMaster. Below is the code for your reference

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class CategoryMaster extends Model

{
    //
}

Eloquent Model Property

In the above model, we didn't mention the table. So we have to declare the table in CategoryMaster Model.

protected $table = '"category_table";

In Eloquent Model, Eloquent consider by default each table has a primary key id with incrementing integer Value. How to Define a protected Primary key property:

protected $primaryKey = '"id";

protected $incrementing = '"false";

if Primary Key is not an integer then you must set the KeyType a string.

protected $keyType = 'string';

Once the Table is declared in the Model, By Default timestamp (Created_at, updated_at) will be true. If you don't want them then you have to set the timestamp to false.

protected $timeStamp = "false";

Eloquent Model and Database Connection

Eloquent model will use Default Database which got configured with your laravel Application. if you wish to have your model connected with other database then you have to use $connection Property. Code is below for your reference.

protected $connection = "Connection-Database-Name";

Fetch / Retrieve Model In Eloquent

Once the Model is Created with Associated table, We can perform all the database operation(CRUD) on it. We will Query / fetch database table associated with model step by step.

Above we have created CategoryMaster Model, Now we will use this model for writing our Eloquent Query as a Example.

$data= App\CategoryMaster::all();

all() method in Eloquent will return all result from the specified model table. We can use various constraint on the all method to filter the table record.

$data = App\CategoryMaster::where('status', 1)->orderBy('id', 'desc')
        ->take(5)->get();

As Eloquent is Query Builder you can use all the Query Builder method for database Operation.

Top 100 Question and Answer with Explanation