//先在application/config/database.php文件中配置好数据库用户名密码等
		$this->load->database();

		$query = $this->db->query('SELECT * FROM test');

		//对象形式返回结果
		foreach ($query->result() as $row)
		{
			echo $row->id . ' ';
			echo $row->content . '<br><br>';
		}

		echo '查询结果数: ' . $query->num_rows();



		$query = $this->db->query('SELECT * FROM test');

		//数组形式返回结果
		foreach ($query->result_array() as $row)
		{
			echo $row['id'] . ' ';
			echo $row['content'] . '<br><br>';
		}


		echo '查询结果数: ' . $query->num_rows();