Python实战之Oracle数据库操作

1. 要想使Python可以操作Oracle数据库，首先需要安装cx_Oracle包，可以通过下面的地址来获取安装包

http://cx-oracle.sourceforge.net/

2. 另外还需要oracle的一些类库，此时需要在运行python的机器上安装Oracle Instant Client软件包，可以通过下面地址获得

http://www.oracle.com/technetwork/database/features/instant-client/index-097480.html

找到符合自己平台的包，然后安装，这里我使用的是rpm包，所以使用以下命令安装

$ sudo rpm -ivh  oracle-instantclient11.2-basic-11.2.0.3.0-1.i386.rpm

装完毕后还需要设置一下环境变量，如下

$ export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/usr/lib/oracle/11.2/client/lib

3. 创建一个简单的python文件，测试安装是否成功

import cx_Oracle

conn = cx_Oracle.connect('fkong/fkong@172.17.23.129/orcl')
cursor = conn.cursor ()
cursor.execute ("select * from dual")
row = cursor.fetchone ()
print row[0]

cursor.close ()
conn.close ()

4. 下面看一个数据库建表和插入操作

import cx_Oracle

conn = cx_Oracle.connect('fkong/fkong@172.17.23.129/orcl')
cursor = conn.cursor ()

cursor.execute ("CREATE TABLE TEST(ID INT, COL1 VARCHAR(32), COL2 VARCHAR(32), COL3 VARCHAR(32))")

cursor.execute ("INSERT INTO TEST (ID, COL1, COL2, COL3)VALUES(1, 'a', 'b', 'c')")
cursor.execute ("INSERT INTO TEST (ID, COL1, COL2, COL3)VALUES(2, 'aa', 'bb', 'cc')")
cursor.execute ("INSERT INTO TEST (ID, COL1, COL2, COL3)VALUES(3, 'aaa', 'bbb', 'ccc')")
conn.commit()

cursor.close ()
conn.close ()

5. 下面再来看看查询，查询通常有两种方式：一种是使用cursor.fetchall（）获取所有查询结果，然后再一行一行的迭代；另一种每次通过cursor.fetchone()获取一条记录，直到获取的结果为空为止。看一下下面的例子：

import cx_Oracle

conn = cx_Oracle.connect('fkong/fkong@172.17.23.129/orcl')
cursor = conn.cursor ()

cursor.execute ("SELECT * FROM TEST")
rows = cursor.fetchall()
for row in rows:
    print "%d, %s, %s, %s" % (row[0], row[1], row[2], row[3])

print "Number of rows returned: %d" % cursor.rowcount

cursor.execute ("SELECT * FROM TEST")
while (1):
    row = cursor.fetchone()
    if row == None:
        break
    print "%d, %s, %s, %s" % (row[0], row[1], row[2], row[3])

print "Number of rows returned: %d" % cursor.rowcount

cursor.close ()
conn.close ()