Explore topic-wise InterviewSolutions in .

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');

We can create all web PAGES of our sites to tell Google and other search engines like Bing, Yahoo etc about the organization of our site content. These search engine web crawlers read this file to more intelligently crawl our sites.

• Firstly we have to create a route for this in your routes/web.php file
  Example
  Route::get('sitemap.xml', '[email protected]')->name('sitemapxml');
• Now you can create SitemapController.php with artisan command php artisan make:controller SitemapController
• Now you can put this CODE in your controller
  public function index() {
      $page = Page::where('status', '=', 1)->get();
      return response()->view('sitemap_xml', ['page' => $page])->header('Content-Type', 'text/xml');
  }
• Now please create a view file in resources/view/sitemap_xml.blade.php file with this code
• Put this code in that created view file
  <?php ECHO '<?xml version="1.0" encoding="UTF-8"?>'; ?>
  <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9
  http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">
  @foreach ($page as $post)
  <url>
  <loc>{{ url($post->page_slug) }}</loc>
  <lastmod>{{ $post->updated_at->TZ('UTC')->toAtomString() }}</lastmod>
  <priority>0.9</priority>
  </url>
  @endforeach
  </urlset>

LARAVEL uses "Blade TEMPLATE Engine". It is a STRAIGHTFORWARD and POWERFUL templating engine that is provided with Laravel.

We have to use the FOLLOWING ARTISAN COMMANDS to enable/disable maintenance mode in LARAVEL 5.

php artisan down

php artisan up

After RUNNING the composer INSTALL in the PROJECT directory, the composer will generate the composer.lock file.It will KEEP a record of all the DEPENDENCIES and sub-dependencies which is being installed by the composer.json.

Laravel involves Eloquent ORM (Object Relational Mapper), which makes it fun to interact with the database. While using Eloquent, every database table CONTAINS their corresponding “MODEL” that is being used for INTERACTION with that table. The eloquent model also ALLOWS the people to insert, update, and delete the RECORDS from the table. We can create Eloquent models using the make:model command.

• One To One relationships
• One To Many relationships
• Many To Many relationships
• Has Many Through relationships
• Polymorphic relationships
• Many To Many Polymorphic relationships

To use multiple databases in Laravel, FOLLOW these steps carefully.

• Ensure these settings in the .env file
• Add these following LINES of CODE in the config/database.php file to clearly define the relationship between the two databases
• EXECUTE the query with particular database.

DB_CONNECTION=mysql
DB_HOST=localhost
DB_PORT=3306
DB_DATABASE=your_db_name
DB_USERNAME=bestinterviewquestion
[email protected]

DB_CONNECTION_SECOND=mysql
DB_HOST_SECOND=localhost
DB_PORT_SECOND=3306
DB_DATABASE_SECOND=your_db_name2
DB_USERNAME_SECOND=bestinterviewquestion
[email protected]

'mysql' => [
    'driver'    => env('DB_CONNECTION'),
    'host'      => env('DB_HOST'),
    'port'      => env('DB_PORT'),
    'database'  => env('DB_DATABASE'),
    'username'  => env('DB_USERNAME'),
    'password'  => env('DB_PASSWORD'),
],

'mysql2' => [
    'driver'    => env('DB_CONNECTION_SECOND'),
    'host'      => env('DB_HOST_SECOND'),
    'port'      => env('DB_PORT_SECOND'),
    'database'  => env('DB_DATABASE_SECOND'),
    'username'  => env('DB_USERNAME_SECOND'),
    'password'  => env('DB_PASSWORD_SECOND'),
],

$users = DB::connection('your_db_name2')->select();

In Laravel, FACADES are used to provide a static interface to classes available inside the application's SERVICE container.

Now, unlike conventional static method CALLS, facades can be mocked in Laravel. It can be done using the shouldRecieve method, which shall RETURN an instance of a FACADE mock.

$value = Cache::get('key');

Cache::shouldReceive('get')->once()->with('key')->andReturn('value');

Soft delete is a laravel feature that helps When models are soft DELETED, they are not actually removed from our database. Instead, a deleted_at TIMESTAMP is SET on the record. To enable soft deletes for a model, we have to specify the soft delete property on the model like this.

In model we have to use namespace
use Illuminate\Database\Eloquent\SoftDeletes;

and we can use this
use SoftDeletes; in our model property.

After that when we will use delete() query then records will not REMOVE from our database. then a deleted_at timestamp is set on the record.

We have to call FACADES in our controller file with this :
use Illuminate\Support\Facades\Storage;

if($REQUEST-&GT;hasFile(file_name')) {
      $file = Storage::putFile('YOUR FOLDER PATH', $request->file('file_name'));
}

You can USE request()-&GT;IP();

You can ALSO use : Request::ip() but in this case, we have to CALL namespace like this: Use Illuminate\Http\Request;

REQUEST()-&GT;ROUTE()->getActionMethod()

Laravel SUPPORTS VARIOUS joins that's are GIVEN below:-

• Inner Join

  DB::table('admin') ->join('contacts', 'admin.id', '=', 'contacts.user_id') ->join('orders', 'admin.id', '=', 'orders.user_id') ->select('USERS.id', 'contacts.phone', 'orders.price') ->get();

• LEFT Join / Right Join

  $users = DB::table('admin') ->leftJoin('posts', 'admin.id', '=', 'posts.admin_id') ->get();
  $users = DB::table('admin') ->rightJoin('posts', 'admin.id', '=', 'posts.admin_id') ->get();

• Cross Join

  $user = DB::table('sizes') ->crossJoin('colours') ->get();

• Advanced Join

  DB::table('admin') ->join('contacts', function ($join) { $join->on('admin.id', '=', 'contacts.admin_id')->orOn(...); }) ->get();

• Sub-Query Joins

  $admin = DB::table('admin') ->joinSub($latestPosts, 'latest_posts', function ($join) { $join->on('admin.id', '=', 'latest_posts.admin_id'); })->get();

with() function is used to eager load in Laravel. Unless of USING 2 or more separate QUERIES to fetch data from the database, we can use it with() method after the first command. It provides a better user experience as we do not have to wait for a LONGER period of time in fetching data from the database.

You can do this in various ways. Steps are given below:-

• Copy .htaccess file from public folder and now paste it into your root.
• Now rename server.php file/page to index.php on your root folder.
• Now you can remove /public word from URL and refresh the page. Now it will work.

Laravel AUTH is the process of identifying the user credentials with the database. Laravel managed it's with the help of sessions which take INPUT parameters LIKE USERNAME and password, for user identification. If the settings match then the user is said to be authenticated.

Auth is in-built functionality provided by Laravel; we have to configure.

We can add this functionality with php ARTISAN make: auth

Auth is used to identifying the user credentials with the database.

1. How to set COOKIE

To set cookie value, we have to use Cookie::put('key', 'value');

To get cookie Value we have to use Cookie::get('key');

To remove cookie Value we have to use Cookie::forget('key')

To Check cookie is exists or not, we have to use Cache::has('key')

LARAVEL provides a powerful and clean API over the SwiftMailer library with drivers for Mailgun, SMTP, AMAZON SES, SparkPost, and send an email. With this API, we can send email on a local SERVER as well as the live server.

Laravel allows us to store email messages in our views files. For example, to manage our emails, we can create an email directory WITHIN our resources/views directory.

public function sendEmail(Request $request, $id)
{
      $user = Users::FIND($id);
      Mail::send('emails.reminder', ['user' => $user], function ($mail) use ($user)  {
           $mail->from('[email protected]', 'Feedback');
           $mail->to($user->email, $user->name)->subject('Thanks Message');
      });
}

1. delete()

In case when we used to delete in Laravel then it REMOVED records from the database table.

$delete = Post::where(‘id’, ‘=’, 1)->delete();

To delete records permanently is not a good THING that’s why laravel used features are called SoftDelete. In this case, records did not REMOVE from the table only delele_at VALUE updated with current date and time.
Firstly we have to add a given code in our required model file.

use SoftDeletes;
protected $dates = ['deleted_at'];

$softDelete = Post::where(‘id’, ‘=’, 1)->delete();

OR

$softDelete = Post::where(‘id’, ‘=’, 1)->softDeletes();

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

$insertGetId = DB::table(‘blogs’)->insertGetId([‘title’ => ‘Best Interview Questions’]);

1. RETRIEVING DATA from session
session()->GET('key');

2. Retrieving All session data
session()->all();

3. Remove data from session
session()->forget('key'); or session()->flush();

4. STORING Data in session
session()->put('key', 'value');

A laravel service CONTAINER is ONE of the most powerful TOOLS that have been used to manage dependencies over the class and perform dependency injections.

• Freedom to manage class dependencies on object creation.
• Service contain as Registry.
• Ability to BIND interfaces to concrete CLASSES.

Laravel installation steps:-

• DOWNLOAD composer from https://getcomposer.org/download (if you don’t have a composer on your system)
• OPEN cmd
• Goto your htdocs folder.
• C:\xampp\htdocs&GT;composer create-project laravel/laravel projectname
  OR
  If you install some particular version, then you can use
  composer create-project laravel/laravel project NAME "5.6"

If you did not MENTION any particular version, then it will install with the latest version.

We can CREATE a helper FILE using Composer. Steps are given below:-

• Please create a "app/helpers.php" file that is in app folder.
• Add
  "files": [
      "app/helpers.php"
  ]
  in "autoload" variable.
• Now UPDATE your composer.json with composer dump-autoload or composer update

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.

DD($array);

The facade gives the “static” interface to all the classes available in the service container of the application. Laravel comes along with many interfaces that provide the ACCESS to almost all the features of Laravel.

All the facades are defined in the NAMESPACE Illuminate\Support\Facades for easy ACCESSIBILITY and usability.

use Illuminate\Support\Facades\Cache;

     ROUTE::get('/cache', function () {

     return Cache::get('PutkeyNameHere');

});

How to create a Stored PROCEDURE

To create a Stored Procedure you can execute given code in your MySQL query builder directly or use phpmyadmin for this.

DROP PROCEDURE IF EXISTS `get_subcategory_by_catid`;
delimiter ;;
CREATE PROCEDURE `get_subcategory_by_catid` (IN IDX int)
BEGIN
SELECT ID, parent_id, title, slug, created_at FROM category WHERE parent_id = idx AND status = 1 ORDER BY title;
END
;;
delimiter ;

After this, you can use this CREATED procedure in your code in Laravel.

$getSubCategories = DB::select(
   'CALL get_subcategory_by_catid('.$item-&GT;category_id.')'
);

It acts as a middleman between a request and a response. Middleware is a type of filtering mechanism used in Laravel application.

• We can create middelware with
  php artisan make:middleware UsersMiddleware
• Here "UsersMiddleware" is the name of Middleware. After this COMMAND a "UsersMiddleware.php" file created in app/Http/Middleware directory.
• After that we have to register that middleware in kernel.php (AVAILABLE in app/Http directory) file in "$routeMiddleware" variable.
  'Users' => \App\Http\Middleware\UsersMiddleware::class,
• Now we can call "Users" middleware where we need it LIKE CONTROLLER or route file.
• We can use it in controller file like this.
  public function __construct() {
     $this->middleware('Users');
  }
• In route file we can use like this.
  Route::group(['middleware' => 'Users'], function () {
     Route::get('/', '[EMAIL protected]');
  });

We can add that PARTICULAR URL or ROUTE in $EXCEPT variable. It is present in the app\Http\Middleware\VerifyCsrfToken.php file.

CLASS VerifyCsrfToken extends BaseVerifier {
      protected $except = [
            'Pass here your URL',
      ];
}

In Laravel, we can USE whereBetween() function to get DATA between two dates.

Users::whereBetween('created_at', [$firstDate, $secondDate])-&GT;get();

Follow these STEPS to SUCCESSFULLY create a package in Laravel:

• CREATING a Folder Structure
• Creating the COMPOSER File
• Loading the Package from the Main Composer.JSON File
• Creating a Service Provider for Package
• Creating the Migration
• Creating the Model for the Table
• Creating a Controller
• Creating a ROUTES File
• Creating the Views
• Updating the Service Provider to Load the Package
• Update the Composer File

Service providers are the fundamentals of bootstrapping laravel applications. All the core services of Laravel are bootstrapped through service providers.

This powerful tools are used by developers to manage CLASS dependencies and perform dependency injection. To create a service provider, we have to use the below-mentioned ARTISAN COMMAND.

You can use php artisan make: provider ClientsServiceProvider artisan command to generate a service provider :

• register function
• boot function

Reverse routing in the laravel means the process that is used to GENERATE the URLs which are BASED on the names or symbols. URLs are being generated based on their route declarations.

With the use of reverse routing, the application becomes more flexible and provides a better interface to the developer for writing cleaner codes in the View.

Route:: get(‘list’, ‘[EMAIL PROTECTED]’);
{{ HTML::link_to_action('[email protected]') }}

In between head, tag put <meta name="csrf-token" content="{{ csrf_token() }}"> and in Ajax, we have to ADD
$.ajaxSetup({
   headers: {
     'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
   }
});

Database migration is like the VERSION control of the database, which allows the team to modify and share the database SCHEMA of the application. Database migrations are paired with the schema builder of Laravel which is used to build the database schema of the application.

It is a type of version control for our database. It is allowing US to modify and share the application's database schema easily.

A migration file contains two methods up() and down().

up() is used to add new tables, columns, or indexes database and the down() is used to reverse the operations performed by the up method.

You can generate a migration & its file with the help of make:migration.

SYNTAX : PHP artisan make:migration blog

A current_date_blog.php file will be create in database/migrations

{{ $USERNAME }} is SIMPLY used to display text contents but {!! $username !!} is used to display CONTENT with HTML tags if EXISTS.

MIDDLEWARE in laravel works as a platform among the REQUEST and the response. It provides the mechanism for INVESTIGATING the HTTP requests which are entering into your application. For instance, middleware in laravel ensures that the user of your particular application is authenticated. If they found that the user is not authenticated, it will redirect the user to the main login PAGE of the application.

Example: If a user is not authenticated and it is trying to access the dashboard then, the middleware will redirect that user to the login page.

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)

DB::connection()->enableQueryLog();

$RESULT = User:where(['status' => 1])->GET();

$log = DB::getQueryLog();

dd($log);

You can create a constants.php page in config folder if does not EXIST. Now you can put constant VARIABLE with value here and can USE with Config::get('constants.VaribleName');

RETURN [
   'ADMINEMAIL' => '[EMAIL protected]',
];
Now we can display with
Config::get('constants.ADMINEMAIL');

Here are some of the reasons why Laravel is considered to be better than CodeIgniter:

You can EXTEND the LOGIN expire time with config\session.php this file location. Just update lifetime the value of the variable. By default it is 'lifetime' =&GT; 120. According to your REQUIREMENT update this variable.

'lifetime' => 180

• EASY Installation
• Supports MVC Architecture
• Ensures HIGH security
• Modular Design
• Object-Oriented LIBRARIES

Laravel 8.0 is incorporated with a NUMBER of latest features such as Laravel JETSTREAM, model directory, MIGRATION squashing, rate limiting improvements, model factory classes, TIME testing helpers, dynamic blade components and, much more. The Laravel 8.0 released on 8th September 2020 with the latest and unique features.

• Time Testing Helpers
• Models Directory
• Migration Squashing
• Laravel Jetstream
• Rate Limiting Improvements
• Model Factory Classes
• Dynamic Blade Components

YES, LARAVEL supports CACHING of popular BACKENDS such as Memcached and Redis.

It is a TYPE of add-ons like PLUGINS or extensions in other CMS. These modules gives us the ability to enhance its FUNCTIONALITY without edit its application FILES.

It is a system that allows USERS to be able to MODIFY their store by uploading a compressed file which contains XML file and SQL file and PHP FILES.

• 2Checkout
• Amazon Pay
• Authorize.Net
• Bank Transfer
• Cash On Delivery
• PayPal
• WorldPay ONLINE Payments
• Free Checkout
• Alipay Pay
• Cheque / MONEY Order
• First Data EMEA Connect etc

• It provides New BACKEND interface in from 2.0
• It GIVES much faster & clear RESPONSIVE Front END now
• Coding changes
• Alternative of VQMOD
• Extension installed
• More Payment Methods
• API etc

• OpenCart is very Simple and Easy-to-Learn
• It is LIGHTWEIGHT eCommerce platform with several eCommerce features.
• Opencart is easy to MODIFY and Understand.
• It OFFERS various shipping and payment methods to choose from and several modules are free.

• User-friendly and Capability : For managing MAGENTO we should have some programming and technical knowledge than for OpenCart. Magento is fully customizable, flexible, having various SEO resources and manyl extensions while OpenCart does not have.
• Support and POPULARITY : Magento is very powerful as compared to OpenCart. Both having their communities and always ready to help the clients. Quality of programmers are very HIGH in Magento as compared to OpenCart.
• Costs of Extensions and Hosting Plans : Magento's cost is double as compared to OpenCart in hosting, extensions and premium templates, SINCE OpenCart is lightweight.

Conclusion : Magento is best choice for large business with HUGE budget and OpenCart is best for small business with low budget. It depends on users to choose a platform according to their need & requirements.

It is ecommerce CMS solution that OFFERS VARIOUS features for online RETAILERS. It is an open SOURCE and free to use which makes it a cost-effective solution for all small and MEDIUM ecommerce sites.

It is a free, simple, powerful and open SOURCE ECOMMERCE PLATFORM that can HELP us to built eCommerce website for SELLING our products & services.