Build and Install cx_Oracle on Mac Leopard Intel

Build and Install cx_Oracle on Mac Leopard Intel

I finally succeeded in building and installing cx_Oracle on a Mac. I will outline the steps that I took. There are many redundant steps that I may later take out. But there are checks that I made on the way that really helped.

The first Mac that I installed cx_Oracle was a 2.4 GHz Intel Core 2 Duo running Mac OSX 10.6.6. It had 4 GB of Memory. Most of my work was done on a terminal window.

Check Python Installation

The OSX comes with a Python interpreter. I ran a check to find the version number.

$ python -V
Python 2.6.1

This was sufficient for my needs. I decided not to upgrade to Python version 2.7.1

Xcode from Apple

The Xcode package is available from Apple Developer. You will need a login account but that is free. Now you do not need Xcode 4. Xcode 3 is sufficient because all we are interested in is the gcc compiler. After you login look for a link that says Looking for Xcode 3? I downloaded X code 3.2.6 and iOS SDK 4.3. It was 4.1 GB in size and is best done when you know you will not be using your Mac.

After the download, the installation went off smoothly. I restarted the Mac and on a terminal window checked that the gcc compiler was installed correctly.

$ which gcc
/usr/bin/gcc

$ gcc -v
gcc version 4.2.1

You can also do   man gcc   to get the online manual for gcc.

Install Oracle Instant Client

The cx_Oracle has a dependency. It needs Oracle Instant Client from Oracle. Click on the link Instant Client for Mac OS X (Intel x86). Accept the license agreement and download Version 10.2.0.4 (64-bit). I tried the 32-bit and it does NOT work. You will need your Oracle account to download the following packages:

• instantclient-basic-10.2.0.4.0-macosx-x64.zip
• instantclient-sdk-10.2.0.4.0-macosx-x64.zip

I created a directory called oracle to unpack the packages. The pathname on my machine was /Users/utcs/oracle. On your machine, it will be your user name instead of utcs. I moved both the basic and sdk packages into theoracle directory and unzipped them. After unzipping the basic package I got a folder instantclient_10_2.

After unzipping the sdk package, I got a folder called instantclient_10_2-1. Inside that folder was another folder called sdk. I moved the folder named sdk inside the folder instantclient_10_2.

From a terminal window I changed directory to sdk. On my machine, the full path name was /Users/utcs/oracle/instantclient_10_2/sdk. There is another .zip file called ottclasses.zip. I unzipped that as follows:

$ unzip ottclasses.zip

It produced a folder called   oracle . I changed directory to   /Users/utcs/oracle/instantclient_10_2 . I ran the following command to copy all the files in the   sdk   folder.

$ cp -R ./sdk/* .
$ cp -R ./sdk/include/* .

The last two commands may not have been necessary. But it makes it easier to locate the header files.

Setting up the Environment Variables

In my home directory /Users/utcs I created a .profile file. Its content was as follows:

export ORACLE_HOME=/Users/utcs/oracle/instantclient_10_2
export DYLD_LIBRARY_PATH=$ORACLE_HOME
export LD_LIBRARY_PATH=$ORACLE_HOME

Restart the machine. Open another terminal window and run the following commands to check that the environment variables have been set properly:

$ source .profile
$ echo $ORACLE_HOME
$ echo $DYLD_LIBRARY_PATH
$ echo $LD_LIBRARY_PATH

You should see the path names printed out correctly. I created two symbolic links in the $ORACLE_HOME directory (/Users/utcs/oracle/instantclient_10_2) as follows:

ln -s libclntsh.dylib.10.1 libclntsh.dylib
ln -s libocci.dylib.10.1 libocci.dylib

If you run the command   ls -l   in that directory you should see the symbolic links.

Building and Installing cx_Oracle

Download from SourceForge cx_Oracle version 5.0.4. You need to get the package that says Source Code only. In your Download folder you will find cx_Oracle-5.0.4.tar. I moved it to /Users/utcs/oracle. To untar, I used the following command:

tar -xvf cx_Oracle-5.0.4.tar

After untarring I had a subdirectory called cx_Oracle-5.0.4. In a terminal window I changed directory to /Users/utcs/oracle/cx_Oracle-5.0.4. I checked in that window that all the environment variables were set properly by doing

echo $ORACLE_HOME
echo $LD_LIBRARY_PATH
echo $DYLD_LIBRARY_PATH
which python
which gcc

I did not have administrative privileges on this Mac so to build I did

python setup.py build

I checked to output. There were many   warning   messages that I ignored. Even a single   error   message would have indicated that the build process did not succeed. I next installed cx_Oracle by

python setup.py install

The install also finished without any error messages.

Test the cx_Oracle installation

On a terminal window type python. It should bring up Python in interactive mode. Then type import cx_Oracle. It should add the package to your path without any errors. Get out of the interactive mode using Control-D.

Now copy and paste this script into a file called Check.py. Change the user name and run it on the command line.

import cx_Oracle, string, getpass

def main():
  # Get password
  pswd = getpass.getpass()
      
  # Build connection string
  user = "CS327E_jdoe"
  host = "rising-sun.microlab.cs.utexas.edu"
  port = "1521"
  sid = "orcl"
  dsn = cx_Oracle.makedsn (host, port, sid)
		    
  # Connect to Oracle and test
  con = cx_Oracle.connect (user, pswd, dsn)
  if (con):
    print "Connection successful"
    print con.version
  else:
    print "Connection not successful"

  con.close()

main()

You should see Connection successful if all the other tests were successful.

I followed the instructions listed here (using the 32-bit downloads from Oracle):http://www.xairon.net/2011/05/guide-installing-cx_oracle-on-mac-os-x/

I then had the same error you listed:

ImportError: dlopen(/Library/Python/2.7/site-packages/cx_Oracle.so, 2): Symbol not found: _OCIAttrGet Referenced from: /Library/Python/2.7/site-packages/cx_Oracle.so Expected in: flat namespace in /Library/Python/2.7/site-packages/cx_Oracle.so

The problem was from Apple's Python distribution running in 64-bit mode by default.

Once I forced the Apple supplied Python to use 32-bit (from Ned's recommendation), it worked!

To do that:

$export VERSIONER_PYTHON_PREFER_32_BIT=Yes

To make it permanent:

$defaults write com.apple.versioner.python Prefer-32-Bit -bool yes