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Mastering the art of database queries is critical in Laravel 10 for creating powerful and data-driven applications. The LEFT JOIN technique, which allows you to integrate data from several tables while including mismatched values from the left table, is one of the foundations of relational databases. This functionality enables you to extract valuable insights from your database and provide detailed reports.

This tutorial will walk you through a full example of using the LEFT JOIN technique in Laravel 10 with MySQL. We will walk you through the process of defining database relationships, migration files, and using LEFT JOIN queries to retrieve and harmonise data from linked tables.

Let’s get started.

Types of Joins

As per the documentation we have following types of joins available –

Inner Join
Left Join
Right Join
Cross Join

What is Left Join?

Left Join – This also works same the matched condition between two or more than two tables. But in this case we also get the rows of left table which doesn’t match with the condition with the right hand sided table. Means we get all rows of left table including values of matched with right table.

How can we use inside an application and get relational data we will see by making an application. Let’s create an application in which we use Left Join.

Laravel Installation

Open terminal and run this command to create a laravel project.

composer create-project laravel/laravel myblog

It will create a project folder with name myblog inside your local system.

To start the development server of laravel –

php artisan serve

URL: http://127.0.0.1:8000

Assuming laravel already installed inside your system.

Create Database & Connect

To create a database, either we can create via Manual tool of PhpMyadmin or by means of a mysql command.

CREATE DATABASE laravel_app;

To connect database with application, Open .env file from application root. Search for DB_ and update your details.

DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_PORT=3306
DB_DATABASE=laravel_app
DB_USERNAME=root
DB_PASSWORD=root

Next,

Setup Migrations & Model

Create migrations and models for Employees and Projects table.

Open project into terminal and run this artisan command.

$ php artisan make:model Employee -m

It will create two files –

Model file Employee.php inside /app/Models folder.
Migration file 2023_08_11_062204_create_employees_table.php inside /database/migrations folder.

$ php artisan make:migration create_projects_table

It will create a migration file 2023_08_11_062234_create_projects_table.php inside /database/migrations folder.

Open xxx_create_employees_table.php and write this following code into it.

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

return new class extends Migration
{
    /**
     * Run the migrations.
     */
    public function up(): void
    {
        Schema::create('employees', function (Blueprint $table) {
            $table->id();
            $table->string("name", 50);
            $table->string("email", 50);
            $table->string("phone_no", 20);
        });
    }

    /**
     * Reverse the migrations.
     */
    public function down(): void
    {
        Schema::dropIfExists('employees');
    }
};

Open xxx_create_projects_table.php and write this following code into it.

<?php

use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

return new class extends Migration
{
    /**
     * Run the migrations.
     */
    public function up(): void
    {
        Schema::create('projects', function (Blueprint $table) {
            $table->id();
            $table->integer('employee_id')->unsigned();
            $table->string("project_name", 100);
            $table->foreign('employee_id')
                ->references('id')->on('employees')
                ->onDelete('cascade');
        });
    }

    /**
     * Reverse the migrations.
     */
    public function down(): void
    {
        Schema::dropIfExists('projects');
    }
};

Migrate Migrations

Back to terminal and run this command to migrate all migrations.

$ php artisan migrate

This command will migrate all.

Insert Test Data (Tables)

We have some mysql queries which will insert test data to employees and projects table.

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Copy command and run into SQL tab of mysql database.

--
-- Dumping data for table `employees`
--

INSERT INTO `employees` (`id`, `name`, `email`, `phone_no`) VALUES
(1, 'Sanjay Kumar', 'sanjay@gmail.com', '8527419630'),
(2, 'Vijay Kumar', 'vijay@gmail.com', '9632587410'),
(3, 'Ashish Kumar', 'ashish@gmail.com', '7896541356');
(4, 'Dhananjay Kumar', 'dhananjay@gmail.com', '7896585296'),
(5, 'Pradeep Kumar', 'pradeep@gmail.com', '7896556565');

--
-- Dumping data for table `projects`
--

INSERT INTO `projects` (`id`, `employee_id`, `project_name`) VALUES
(1, 1, 'Project 4'),
(2, 2, 'Project 7'),
(3, 3, 'Project 50');

Create Controller

Open project into terminal and run this command.

$ php artisan make:controller SiteController

It will create SiteController.php file inside /app/Http/Controllers folder.

Open SiteController.php and write this code into it.

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use App\Models\Employee;

class SiteController extends Controller
{
    public function getData()
    {
        $data = Employee::leftJoin("projects", function ($join) {
          
            $join->on("projects.employee_id", "=", "employees.id");
          
        })->get();

        echo "<pre>";
        print_r($data);
    }
}

There are 2 methods available by which you can use left join concept.

Method #1

$data = Employee::leftJoin("projects", function ($join) {
     $join->on("projects.employee_id", "=", "employees.id");
})->get();

Method #2

$data = Employee::leftJoin("projects", "projects.employee_id", "=", "employees.id")->get();

Query will be,

select * from `employees` left join `projects` on `projects`.`employee_id` = `employees`.`id`

Add Route

Open web.php file from /routes folder.

//...

use App\Http\Controllers\SiteController;

Route::get("left-join", [SiteController::class, "getData"]);

//...

Application Testing

Run this command into project terminal to start development server,

php artisan serve

URL: http://127.0.0.1:8000/left-join

You will get your data set at output screen.

Complete Data of Left table + Matched data with Right Table

Advanced Cases in Left Join

Assuming these cases, you can take a hint from these.

Example 1: Laravel Eloquent leftJoin() with 2 Tables

$users = User::leftJoin('posts', 'users.id', '=', 'posts.user_id')                ->get(['users.*', 'posts.descrption']);

Generated Query

select `users`.*, `posts`.`descrption` from `users`  left join `posts` on `users`.`id` = `posts`.`user_id`

Example 2: Laravel Eloquent leftJoin() with 3 Tables

$users = User::leftJoin('posts', 'posts.user_id', '=', 'users.id')               ->leftJoin('comments', 'comments.post_id', '=', 'posts.id')               ->get(['users.*', 'posts.descrption']);

Generated Query

select `users`.*, `posts`.`descrption` from `users`  left join `posts` on `posts`.`user_id` = `users`.`id`  left join `comments` on `comments`.`post_id` = `posts`.`id`

Example 3: Laravel Eloquent leftJoin() with Multiple Conditions

$users = User::leftJoin('posts', 'posts.user_id', '=', 'users.id')             ->where('users.status', 'active')
->where('posts.status','active')
->get(['users.*', 'posts.descrption']);

Generated Query

select `users`.*, `posts`.`descrption` from `users`  left join `posts` on `posts`.`user_id` = `users`.`id`  where `users`.`status` = active and `posts`.`status` = active

We hope this article helped you to learn about Laravel 10 MySQL Left Join Example Tutorial in a very detailed way.

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