$sql = 'SELECT * FROM `menu` WHERY `published` = :published';
$params = array(
':published'=>1
);
$stmt = self::$connection->prepare($sql);
$stmt->execute($params);
$result = $stmt->fetchAll();
prepare($sql)
prepare(SELECT * FROM `menu` WHERY `published` = :published')
execute($params)
execute(array(':published'=>1 ))