Manytomany relation in Laravel - php

Question

I'm working in Laravel and need help with database relations. I have three tables:
projects:
+------------+--------------------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+--------------------------------+------+-----+---------+----------------+
| id | int(10) unsigned | NO | PRI | NULL | auto_increment |
| title | varchar(191) | NO | | NULL | |
| url | varchar(191) | YES | | NULL | |
| updated | bigint(20) unsigned | YES | | NULL | |
| type | enum('adobe','invision','pdf') | NO | | NULL | |
| preview_id | int(10) unsigned | YES | MUL | NULL | |
+------------+--------------------------------+------+-----+---------+----------------+
users:
+----------------+------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------------+------------------+------+-----+---------+----------------+
| id | int(10) unsigned | NO | PRI | NULL | auto_increment |
| name | varchar(255) | NO | | NULL | |
| email | varchar(150) | NO | UNI | NULL | |
| password | varchar(179) | NO | UNI | NULL | |
| remember_token | varchar(100) | YES | | NULL | |
+----------------+------------------+------+-----+---------+----------------+
projects_users
+------------+------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+------------------+------+-----+---------+----------------+
| id | int(10) unsigned | NO | PRI | NULL | auto_increment |
| project_id | int(10) unsigned | YES | MUL | NULL | |
| user_id | int(10) unsigned | NO | MUL | NULL | |
+------------+------------------+------+-----+---------+----------------+
Situation: There are several projects, and multiple users can work on multiple projects (ManyToMany).
I need to select (SELECT-statement) all users working on project with e.g ID 1.
How would I do that in plain SQL, and how would I do that in Laravel code (without a raw-sql-query function).
I already looked here but I ain't really catching it.
Thanks!

Answer 1

Use the whereHas() method:
$users = User::whereHas('projects', function($q) use($projectId) {
$q->where('id', $projectId);
})->get();

Answer 2

class Project extends Model{
public function users()
{
return $this->belongsToMany('App\User', 'projects_users');
}
}
class User extends Model{
public function projects()
{
return $this->belongsToMany('App\Project', 'projects_users');
}
}
$project = Project::find(1);
$project->users //list of all the users