Top 50 Laravel Interview Questions & Answers

Following are frequently asked Laravel and PHP related interview questions for freshers as well as experienced candidates to get the right job.

1) What is Laravel?

Laravel is an open-source widely used PHP framework. The platform was intended for the development of web application by using MVC architectural pattern. Laravel is released under the MIT license.

Therefore, its source code is hosted on GitHub. It is a reliable PHP framework as it follows expressive and accurate language rules.

2) Define composer.

It is an application-level package manager for PHP. It provides a standard format for managing PHP software dependencies and libraries.

3) What is HTTP middleware?

HTTP middleware is a technique for filtering HTTP requests. Laravel includes a middleware that checks whether application user is authenticated or not.

4) Name aggregates methods of query builder.

Aggregates methods of query builder are: 1) max(), 2) min(), 3) sum(), 4) avg(), and 5) count().

5) What is a Route?

A route is basically an endpoint specified by a URI (Uniform Resource Identifier). It acts as a pointer in Laravel application.

Most commonly, a route simply points to a method on a controller and also dictates which HTTP methods are able to hit that URI.

6) Why use Route?

Routes are stored inside files under the /routes folder inside the project's root directory. By default, there are a few different files corresponding to the different "sides" of the application ("sides" comes from the hexagonal architecture methodology).

7) What do you mean by bundles?

In Laravel, bundles are referred to as packages. These packages are used to increase the functionality of Laravel. A package can have views, configuration, migrations, routes, and tasks.

8) 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.

9) What is a Controller?

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

10) Explain reverse routing in Laravel.

Reverse routing is a method of generating URL based on symbol or name. It makes your Laravel application flexible.

12) Explain traits in Laravel.

Laravel traits are a group of functions that you include within another class. A trait is like an abstract class. You cannot instantiate directly, but its methods can be used in concreate class.

13) 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.

14) How will you register service providers?

You can register service providers in the config/app.php configuration file that contains an array where you can mention the service provider class name.

15) Where will you define Laravel's Facades?

All facades of Laravel have defined in Illuminate\Support\Facades namespace.

16) State the difference between get and post method.

Get method allows you to send a limited amount of data in the header. Post allows you to send a large amount of data in the body.

17) List default packages of Laravel 5.6.

Default packages of Laravel 5.6 are: 1) Envoy, 2) Passport, 3) Socialite, 4) Cashier, 5) Horizon, and 6) Scout.

18) What is service container in Laravel?

Service container is a tool used for performing dependency injection in Laravel.

19) How can you enable query log in Laravel?

You can use enableQueryLog method to enable query log in Laravel.

20) Explain the concept of events in Laravel.

An event is an occurrence or action that help you to subscribe and listen for events that occur in Laravel application. Some of the events are fired automatically by Laravel when any activity occurs.

21) Explain dependency injection and their types.

It is a technique in which one object is dependent on another object. There are three types of dependency injection: 1) Constructor injection, 2) setter injection, and 3) interface injection.

22) 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.

23) Explain validation concept in Laravel.

Validations are an important concept while designing any Laravel application. It ensures that the data is always in an expected format before it stores into the database. Laravel provides many ways to validate your data.

Base controller trait uses a ValidatesRequests class which provides a useful method to validate requests coming from the client machine.

24) What does ORM stand for?

ORM stands for Object Relational Mapping

25) 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.

26) List available types of relationships in Laravel Eloquent.

Types of relationship in Laravel Eloquent are: 1) One To One 2) One To Many 3) Many To Many 4) Has Many Through, and 5) Polymorphic Relations.

27) Name the Template Engine utilized by Laravel.

Blade is a powerful template engine utilized by Laravel.

28) Name databases supported by Laravel.

Laravel supports the following databases:

• PostgreSQL
• SQL Server
• SQLite
• MySQL

29) Why are migrations important?

Migrations are important because it allows you to share application by maintaining database consistency. Without migration, it is difficult to share any Laravel application. It also allows you to sync database.

30) Define Lumen

Lumen is a micro-framework. It is a smaller, and faster, version of a building Laravel based services, and REST API's.

31) Explain PHP artisan

An artisan is a command-line tool of Laravel. It provides commands that help you to build Laravel application without any hassle.

32) How can you generate URLs?

Laravel has helpers to generate URLs. This is helpful when you build link in your templates and API response.

33) Which class is used to handle exceptions?

Laravel exceptions are handled by App\Exceptions\Handler class.

34) 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

35) Explain fluent query builder in Laravel.

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

36) What is the use of dd() function?

This function is used to dump contents of a variable to the browser. The full form of dd is Dump and Die.

37) List out common artisan commands used in Laravel.

Laravel supports following artisan commands:

• PHP artisan down;
• PHP artisan up;
• PHP artisan make:controller;
• PHP artisan make:model;
• PHP artisan make:migration;
• PHP artisan make:middleware;

38) How to configure a mail-in Laravel?

Laravel provides APIs to send an email on local and live server.

39) 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.

40) Differentiate between delete() and softDeletes().

• delete(): remove all record from the database table.
• softDeletes(): It does not remove the data from the table. It is used to flag any record as deleted.

41) How can you make real time sitemap.xml file in Laravel?

You can create all web pages of a website to tell the search engine about the organizing site content. The crawlers of search engine read this file intelligently to crawl a website.

42) 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.

43) How will you check table is exists or in the database?

Use hasTable() Laravel function to check the desired table is exists in the database or not.

44) What is the significant difference between insert() and insertGetId() function in Laravel?

• Insert(): This function is simply used to insert a record into the database. It not necessary that ID should be autoincremented.
• InsertGetId(): This function also inserts a record into the table, but it is used when the ID field is auto-increment.

45) Explain active record concept in Laravel.

In active record, class map to your database table. It helps you to deal with CRUD operation.

46) List basic concepts in Laravel?

Following are basic concepts used in Laravel:

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

47) Define Implicit Controller.

Implicit Controllers help you to define a proper route to handle controller action. You can define them in route.php file with Route:: controller() method.

48) How to use the custom table in Laravel Model?

In order to use a custom table, you can override the property of the protected variable $table.

49) What is MVC framework?

It is Model, View, and Controller:

• Model: Model defines logic to write Laravel application.
• View: It covers UI logic of Laravel application.
• Controller: It is work as an interface between Model, and View. It is a way how the user interacts with an application.

50) 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.