public function selectById($id)
	{
		$sql = "SELECT * FROM `$this->tableName` WHERE `$this->pkColName` = %d ";
		$stmt = $this->pdo->prepare(sprintf($sql, $id));
		$res = $stmt->execute();

		if ($res === false) {
			return null;
		}

		$rows = $stmt->fetchAll();

		if (count($rows) !== 1) {
			return null;
		}

		return $this->prepareEntity($rows[0]);
	}