python - 无法将 Python 连接到 Oracle

Question

我想使用 cx_Oracle 将 Python 连接到本地 Oracle。我知道为了建立连接，我应该知道本地 IP、端口和 SID。所以我通过以下步骤获取这些信息：

本地IP：

import socket
#get local IP:
localhost = socket.gethostbyname(socket.gethostname())

端口： 这是来自我的listener.ora，所以我使用端口 1521。

# listener.ora Network Configuration File: C:\app\413022472\product\12.2.0\dbhome_1\network\admin\listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = CLRExtProc)
      (ORACLE_HOME = C:\app\413022472\product\12.2.0\dbhome_1)
      (PROGRAM = extproc)
      (ENVS = "EXTPROC_DLLS=ONLY:C:\app\413022472\product\12.2.0\dbhome_1\bin\oraclr12.dll")
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = DESKTOP-2RE9AJU.local)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
  )

DEFAULT_SERVICE_LISTENER = (orcl)

sid：这让我很困扰。我尝试了很多，但仍然无法获得正确的 sid。这是来自我的tnsnames.ora：

# tnsnames.ora Network Configuration File: C:\app\413022472\product\12.2.0\dbhome_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.

LISTENER_ORCL =
  (ADDRESS = (PROTOCOL = TCP)(HOST = DESKTOP-2RE9AJU.local)(PORT = 1521))


ORACLR_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
    (CONNECT_DATA =
      (SID = CLRExtProc)
      (PRESENTATION = RO)
    )
  )

ORCL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl)
    )
  )

这是我select instance_name from v$instance;在sqlplus中运行时得到的：

INSTANCE_NAME
--------------------------------
orcl

我尝试了以下方法：

import cx_Oracle
import socket
#get local IP:
localhost = socket.gethostbyname(socket.gethostname())
#generate dsn:
dsn = cx_Oracle.makedsn(localhost, '1521', service_name = 'orcl')
#make connection:
conn = cx_Oracle.connect("c##scott", "tiger", dsn) 

这给了我：DatabaseError:ORA-12514, TNS:listener does not currently know of service requested in connect descriptor

我也试过dsn = cx_Oracle.makedsn(localhost, '1521', sid = 'orcl') 这给了我：ORA-12505: TNS:listener does not currently know of SID given in connect descriptorD

我应该说我更改了 listener.ora 和 tnsnames.ora 中的文本，但我不记得细节了。谁能帮我连接成功？

标签： pythonoraclecx-oracle

Answer 1

我将使用本Oracle 教程中的一个片段（请记住相应地更改用户/密码）。

import cx_Oracle
con = cx_Oracle.connect('pythonhol/welcome@127.0.0.1/orcl')
print con.version
con.close()

这是官方cx_Oracle 文档的链接。

最后，在这个 GitHub URL 上，您可以找到几个更新的示例，这些示例可能有助于加快您的工作。