/**
* Deletes existing rows.
*
* @param array|string $where SQL WHERE clause(s).
* @return int The number of rows deleted.
*/
public function delete($where)
{
$pk = $this->fetchRow($where)->pk;
$object = parent::delete($where);
try {
unset(self::$_sites[$pk]);
} catch (Exception $e) {
}
return $object;
}