public function _add_id_column_conditions(&$query)
{
$query[] = "WHERE";
$keys = is_array($this->_get_id_column_name()) ? $this->_get_id_column_name() : array($this->_get_id_column_name());
$first = true;
foreach ($keys as $key) {
if ($first) {
$first = false;
} else {
$query[] = "AND";
}
$query[] = $this->_quote_identifier($key);
$query[] = "= ?";
}
}