环境描述：
操作系统：ubuntu 12.04
Python 环境： python2.7 
# Ubuntu
# apt-get install python-pip python-dev

# Centos
# yum -y install epel-release
# yum -y install python-pip python python-devel

2 cx_Oracle安装步骤

1. 确定ORACLE数据库版本，如11.2.0.4

2. 到ORACLE https://www.oracle.com/technetwork/topics/linuxx86-64soft-092277.html 官方网上下载对应的软件包

instantclient-basic-linux.x64-11.2.0.4.0.zip
instantclient-sdk-linux.x64-11.2.0.4.0.zip

3. 将包上传到服务器上

4. 解压到当前目录下，拷贝到/usr/local下

# unzip instantclient-basic-linux.x64-11.2.0.4.0.zip 
# unzip instantclient-sdk-linux.x64-11.2.0.4.0.zip 
# mv instantclient_11_2 /usr/local/

5. 执行以下命令

# echo "/usr/local/instantclient_11_2" > /etc/ld.so.conf.d/oracle-instantclient.conf
# ldconfig

6. 安装依赖包

# Ubuntu
# apt-get install libaio-dev

# Centos
# yum install install libaio-devel

7. 使用pip安装cx_Oracle

# pip install cx_Oracle

【注】部分机器出现以下报错

Downloading/unpacking cx_Oracle
  Cannot fetch index base URL http://pypi.python.org/simple/
  Could not find any downloads that satisfy the requirement cx_Oracle
No distributions at all found for cx_Oracle
Storing complete log in /root/.pip/pip.log

解决办法

#  pip install --index-url=https://pypi.python.org/simple/ cx_Oracle

 8. 在python脚本中测试连接Oracle实例，代码如下：

import cx_Oracle
try:
        conn = cx_Oracle.connect(
            'username/password@xxxxx:1521/instance_name')
    except Exception as e:
        print("connect oracle error!!")
        logger.error(e)
else:
    cur = conn.cursor()
    ......