/**
* Load a list of database rows (numeric column indexing)
* If <var>key</var> is not empty then the returned array is indexed by the value
* the database key. Returns <var>null</var> if the query fails.
*
* @param string $key The field name of a primary key
* @return array If <var>key</var> is empty as sequential list of returned records.
*
* @throws \RuntimeException
*/
public function loadRowList($key = null)
{
$resultArray = $this->_db->loadRowList($key);
return $this->_nullToArray($resultArray);
}
