Ilmar Kerm

Oracle, databases, Linux and maybe more

Connect to Autonomous database using python thin driver

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Oracle recently released a thin driver for Python, meaning it does not require any Oracle client installation (like cx_Oracle does) and it is written natively in Python – one benefit of which is that it works on all platforms where Python is present, including ARM64.

You can read more about it here: https://levelup.gitconnected.com/open-source-python-thin-driver-for-oracle-database-e82aac7ecf5a

Interestingly it is not yet trivial to find examples, on how to use the new thin driver to connect to Oracle Autonomous Database.

By default Autonomous database requites mTLS connections, so first create and download the Instance wallet for your Autonomous database (zip file), do remember the password you set. Unzip and transfer ewallet.pem and tnsnames.ora to your Python host.

# Create directory for wallet files
$ mkdir wallet
$ pwd
/home/ilmar/wallet

# Transport ewallet.pem and tnsnames.ora to that directory
$ ls /home/ilmar/wallet/
ewallet.pem
tnsnames.ora

If you have not yet done so, install the pythoin thin driver.

$ pip3.9 install --user oracledb
Collecting oracledb
  Downloading oracledb-1.1.1-cp39-cp39-manylinux_2_17_aarch64.manylinux2014_aarch64.whl (6.7 MB)
     |████████████████████████████████| 6.7 MB 24.1 MB/s 
Collecting cryptography>=3.2.1
  Downloading cryptography-38.0.1-cp36-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.manylinux_2_24_aarch64.whl (3.7 MB)
     |████████████████████████████████| 3.7 MB 34.9 MB/s 
Collecting cffi>=1.12
  Downloading cffi-1.15.1-cp39-cp39-manylinux_2_17_aarch64.manylinux2014_aarch64.whl (448 kB)
     |████████████████████████████████| 448 kB 90.9 MB/s 
Collecting pycparser
  Downloading pycparser-2.21-py2.py3-none-any.whl (118 kB)
     |████████████████████████████████| 118 kB 119.8 MB/s 
Installing collected packages: pycparser, cffi, cryptography, oracledb
Successfully installed cffi-1.15.1 cryptography-38.0.1 oracledb-1.1.1 pycparser-2.21

Connect from Python code to Autonomous database, connect.py

import oracledb, os

db = oracledb.connect(
       user=os.environ['ORACLE_USER'],
       password=os.environ['ORACLE_PASSWORD'],
       dsn=os.environ['ORACLE_TNS'],
       config_dir="/home/ilmar/wallet",
       wallet_location="/home/ilmar/wallet",
       wallet_password="wallet_password_here")

with db.cursor() as c:
    for row in c.execute("SELECT owner, object_name FROM all_objects FETCH FIRST 10 ROWS ONLY"):
        print(row)

db.close()

Execute

export ORACLE_USER=my_database_username
export ORACLE_PASSWORD=my_database_password
export ORACLE_TNS=connection_identifier_from_tnsnames.ora

$ python3.9 connect.py 
('SYS', 'ORA$BASE')
('SYS', 'DUAL')
('PUBLIC', 'DUAL')
('PUBLIC', 'MAP_OBJECT')
('SYS', 'SYSTEM_PRIVILEGE_MAP')
('SYS', 'I_SYSTEM_PRIVILEGE_MAP')
('PUBLIC', 'SYSTEM_PRIVILEGE_MAP')
('SYS', 'TABLE_PRIVILEGE_MAP')
('SYS', 'I_TABLE_PRIVILEGE_MAP')
('PUBLIC', 'TABLE_PRIVILEGE_MAP')

Here I used Oracle Linux 8 sever running on Ampere (ARM64) in Oracle Cloud Always Free Tier. No Oracle database client or Instantclient was installed.

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Ilmar Kerm