/**
* Call a function as a property
*
* @param string $key
* @return mixed
*/
public function __call_property($key)
{
$result = parent::__call_property($key);
// when we recive a relation we execute it and save it
// to the data to avoid mutlitple queries
if ($result instanceof Model_Relation) {
return $this->_data_store[$key] = $result->run();
}
return $result;
}