public function select_list($key = NULL, $value = NULL)
{
if (!$key) {
$key = $this->pk();
}
if (!$value) {
$value = $this->tk();
}
$query = DB::select($key, $value)->from($this->_table);
if ($this->_sorting) {
foreach ($this->_sorting as $field => $direction) {
$query->order_by($field, $direction);
}
}
return $query->execute($this->_db)->as_array($key, $value);
}