laravel check if value is in table code example

Example 1: laravel check record exists

$user = User::where('email', '=', Input::get('email'))->first();
if ($user === null) {
   // user doesn't exist
}

Example 2: check if column has value in laravel eloquent

->where(function ($query) {
  $query->whereNull('exam_ends_at')
    ->orWhere('exam_ends_at', '>', Carbon::now());
})