如何使用Laravel中的insert插入数据库中避免重复输入？

hi i have developed my project in Laravel 4.2 version and i have an array of record and i want to insert this data into database using built-in insert() function but i want to update those entries which are already inserted otherwise insert the record. Can anyone help me here is my sample code

public static function followAllUsers($user_data) {
  $responce = array();
  $data = array();
  foreach ($user_data['following_id'] as $key => $value) {
    $following = UserBussinessLogic::checkAndValidateUser($value);
    if ($following != true) {
      $responce = Utility::Responce('invalid_user', FALSE, $value);
      break;
    } else {
      if (FriendBussinessLogic::isAlreadyFollowed($user_data['id'], $value)) {
        continue;
      }
      $data[] = array('follower_id' => $user_data['id'], 'following_id' => $value, 'created_at' => date('Y-m-d H:i:s'));
      $followData['notifyAbleUsers'][] = $value;
    }
  }
  if ($following) {
    if (!empty($data)) {
      if (Friend::insert($data)) {
        $followData['created_at'] = date('Y-m-d H:i:s');
        $followData['follower_id'] = $user_data['id'];
        $responce = Utility::Responce('friend_followed', TRUE, $followData);
      } else {
        $responce = Utility::Responce('general_error', FALSE);
      }
    } else {
      $responce = Utility::Responce('already_followed', TRUE);
    }
  }

  return $responce;
}

Thank you

A little lesser known function that is also available in Laravel 4.2 is: updateOrCreate

Here's an example on how to use it:

// If there's a flight from Oakland to San Diego, set the price to $99.
// If no matching model exists, create one.

$flight = App\Flight::updateOrCreate(
    ['departure' => 'Oakland', 'destination' => 'San Diego'],
    ['price' => 99]
);