Check out example codes for "if notexists in laravel query". It will help you in understanding the concepts better.

Code Example 1

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

Code Example 2

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

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