PHP

laravel exists eloquent

//It depends if you want to work with the user afterwards or only check
//if one exists.

//If you want to use the user object if it exists:

$user = User::where('email', '=', Input::get('email'))->first();
if ($user === null) {
   // user doesn't exist
}
//And if you only want to check
if (User::where('email', '=', Input::get('email'))->count() > 0) {
   // user found
}
//Or even nicer

if (User::where('email', '=', Input::get('email'))->exists()) {
   // user found
}

laravel exists eloquent

if (DB::table('orders')->where('finalized', 1)->doesntExist()) {
    // ...
}