public function columns()
{
if (!isset($this->_columns)) {
$this->_columns = array();
foreach ($this->_connection->execute("SHOW COLUMNS FROM " . $this->_name->quoted()) as $c) {
$column = $c['Field'];
unset($c['Field']);
$this->_columns[$column] = $c;
}
}
return $this->_columns;
}