Laravel User and Profile One-to-One Relationship

This project demonstrates a simple one-to-one relationship between the User and Profile models in Laravel. The relationship is established using foreign key constraints and Eloquent relationships.

Features

• One-to-One Relationship between User and Profile
• One-to-many Relationship between Post and Comment
• many-to-many Relationship between 'Role' and 'User'

Project Setup

Prerequisites

Make sure you have the following installed:

• PHP (>=7.4)
• Composer
• Laravel (>=8.x)
• MySQL or another compatible database

Installation

1. Clone the repository

git clone https://github.com/Remonhasan/orm-relationships.git
cd your-repo-name

Clone the repository

composer install

Setup env

cp .env.example .env

Generate Key

php artisan key:generate

Setup Database

DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_PORT=3306
DB_DATABASE=your_database_name
DB_USERNAME=your_database_username
DB_PASSWORD=your_database_password

Run Migration

php artisan migrate

Seed Database

php artisan db:seed

One-to-One Relationship Diagram

The following diagram illustrates the one-to-one relationship between the Usersand Profiles tables:

Users and Profiles Relationship

Users		Profiles
name		id
id	<------------->	user_id
email		bio
password		created_at
		updated_at

Access Relationship

$user = User::find(1);
$profile = $user->profile; // Access the user's profile

$profile = Profile::find(1);
$user = $profile->user; // Access the profile's user

One-to-Many Relationship Diagram

The following diagram illustrates the one-to-many relationship between the Posts and Comments tables:

Posts and Comments Relationship

Posts		Comments
title		id
id	<------------>>	post_id
content		comment

Access Relationship

// Find all comments by Post 
$post = Post::find(1); // Get the post with ID 1

// Access comments associated with the post
$comments = $post->comments;

foreach ($comments as $comment) {
    echo $comment->comment . "<br>";
}


// Find Post by Comment  
$comment = Comment::find(1); // Get the comment with ID 1

// Access the post associated with the comment
$post = $comment->post;

echo $post->title; // Outputs the title of the post

Many-to-Many Relationship Diagram

The following diagram illustrates the one-to-many relationship between the Roles, users and role_users tables:

Define Relationship

// User.php
public function roles()
{
    return $this->belongsToMany(Role::class, 'role_users');
}

// Role.php
 // Define the many-to-many relationship
public function users()
{
    return $this->belongsToMany(User::class);
}

Access Relationship

// UserController.php

// Assign Roles
public function assignRoles($userId)
{
    // Find the user by ID
    $user = User::find($userId);

    // Check if user exists
    if (!$user) {
        return dd('User not found.');
    }

    // Assign roles (you can use attach with a single or multiple role IDs)
    $user->roles()->attach([1, 2, 3]); // Example: Attach roles with IDs 1, 2, and 3

    // Dump the user with attached roles
    return dd($user->load('roles')); // This will show the user with their roles
}

// Removing Roles from a User
public function removeRoles($userId)
{
    // Find the user by ID
    $user = User::find($userId);

    // Check if user exists
    if (!$user) {
        return dd('User not found.');
    }

    // Get a specific role to detach (or you can detach all)
    $role = Role::find(1); // Assuming you want to detach role with ID 1

    // Remove the role from the user
    $user->roles()->detach($role); // Detach a specific role

    // Or detach all roles:
    // $user->roles()->detach(); // Detach all roles

    // Dump the user with the remaining roles
    return dd($user->load('roles'));
}

// Syncing Roles for a User
public function syncRoles($userId)
{
    // Find the user by ID
    $user = User::find($userId);

    // Check if user exists
    if (!$user) {
        return dd('User not found.');
    }

    // Sync roles (this will remove all current roles and only keep roles with IDs 1 and 2)
    $user->roles()->sync([1, 2]);

    // Dump the user with the synced roles
    return dd($user->load('roles'));
}