code: protected function getColumnValue($id)
      {
          $value = $this
              ->getQuery() // we want the raw DB value, not the Model value as that can be mutated.
              ->where($this->key, $id)
              ->value($this->column);
  
          if (is_null($value)) {
              throw new \OutOfRangeException("Cursor key {$id} does not exist or has a null value.");
          }
  
          return $value;
      }
docs: Get the column value for the provided id.
  
  @param $id
  @return mixed
  @throws \OutOfRangeException
  if the id does not exist.