belongs to laravel relationship code example

Example 1: how to use where relationship laravel

Event::with(["owner", "participants" => function($q) use($someId){
    $q->where('participants.IdUser', '=', 1);
    //$q->where('some other field', $someId);
}])

Example 2: laravel detach

// Detach a single role from the user...
$user->roles()->detach($roleId);

// Detach all roles from the user...
$user->roles()->detach();

Example 3: laravel how to query belongsTo relationship

$movies = Movie::whereHas('director', function($q) {
    $q->where('name', 'great');
})->get();

Example 4: eloquent relationships

$roles = App\User::find(1)->roles()->orderBy('name')->get();