What causes this query builder error in my Laravel 8 app? [closed]

I am working on a Laravel 8 app with users, roles and permissions.

I try to get the current user’s list of permissions.

In appModelsPermission.php I have:

class Permission extends Model {
  use HasFactory;

  protected $fillable = [
    'name', 'list'
  ];
}

In appModelsRole.php I have:

class Role extends Model {
  use HasFactory;

  protected $fillable = [
    'name', 'permission_id'
  ];
}

In the controller, I first get the user’s role id:

$user_role = User::where('email', $user->getMail())->first()->role_id;

Then, the list of permissions:

$user_permissions = Permission::select (
  "roles.name as role_name",
  "permissions.list as permissions_list",
)
->leftJoin("permissions", "roles.permission_id", "=", "permissions.id")
->where('roles.id', $user_role)
->get();

The above is intended to be the equivalent of this MySQL query, that works:

SELECT roles.name as role_name, permissions.list AS permissions_list
FROM roles LEFT
JOIN permissions ON roles.permission_id = permissions.id WHERE roles.id = 1

The problem

The Laravel query builder you can see above fails with this message:

Syntax error or access violation: 1066 Not unique table/alias: 'permissions' (SQL: select `roles`.`name`, `permissions`.`list` from `permissions` left join `permissions` on `roles`.`permission_id` = `permissions`.`id` where `roles`.`id` = 1)

I can’t understand why, since I have tested the MySQL query in phpMyAdmin and it works.

Where is my mistake?

Answer

->leftJoin("permissions", "roles.permission_id", "=", "permissions.id")

should be ->leftJoin("roles", "roles.permission_id", "=", "permissions.id")