Deploying cx_Oracle in Windows
cx-oracle, oracle11g, python, windows
Solution
I tried a lot of ways to finally solve the problem. Since I think I should write a comprehensive answer, I will write the problems that I faced and their solutions respectively; hoping it can help others. I also changed the question's name to an appropriate one. Here's what I've been through during installation of `cx_Oracle` module in Windows 7 - 32 bit version(I think other versions of windows would have similar solutions, but I'm not sure):
I have tried to install `cx_Oracle` using `easy_install` and I got the error `No oracle client installed`. I have downloaded oracle basic instant client and oracle sdk instant client for windows from Oracle Official Website and installed it via following steps:
Unzip oracle basic instant client into directory `C:\oracle\instant_client_11_1\`.
Unzip oracle sdk instant client and copy folder `sdk` into the directory `C:\oracle\instant_client_11_1\`, consequently we have a directory as `C:\oracle\instant_client_11_1\sdk\`.
Add `C:\oracle\instant_client_11_1\` to the end of the `PATH` environment variable.
Add a new variable named `ORACLE_HOME` and set `C:\oracle\instant_client_11_1\` for the value.
Restart computer.
I tried to install `cx_Oracle` using `easy_install` again and I got error `command ‘gcc’ failed: no such file or directory` and in some cases `unable to find vcvarsall.bat`; this was because I didn’t have a C++ compiler, so I followed these steps to solve it:
Download Microsoft Visual C++ and install it.
Download MinGW and install it; note that you must install GCC module.
Add `C:\MinGW\` and `C:\MinGW\bin\`(which contains `gcc.exe`) to the end of the `PATH` environment variable.
I tried to install `cx_Oracle` using `easy_install` again and I got error `command ‘gcc’ failed with exit status 1`; I tried this step to solve it:
Open file `C:\Python27\Lib\distutils\ cygwincompiler.py` and remove all `–mno-cygwin` occurrences in this file; this is because recent versions of `GCC` has removed `–mno-cygwin` option and it shouldn’t be there.
I tried to install `cx_Oracle` using `easy_install` and it worked.
But during searching in the internet I found a couple of tricks that may be useful:
If you got error `no module named win32api`, it’s because you didn’t install win32 extensions of python on your computer you should download `pywin32` module from Source Forge and install it.
If you didn’t succeed anyway, you can try an older version of `cx_Oracle`; but keep in mind all we talked about in the above lines. You can find all versions of `cx_Oracle` here.
If you want to use `sqlplus` you should do some other steps too. For this purpose search the internet.
Problem
I'm trying to use `cx_Oracle` module in python to access a remote database and insert or delete rows in tables. BTW I have downloaded oracle instant client 11.1 and also odbc and sqlplus versions. I have set environment variables `ORACLE_HOME` and `TNS_ADMIN` to directory I have unzipped files there and add this this directory to the `PATH` variable. As I googled I think there should be some `.ora` files but I can't find them. I can use `sqlplus` commands from command line, but my main problem is that I can't install and use `cx_Oracle`. I don't want to use any command line scripts; I just want to use `cx_Oracle` as an API. Can anyone give me a complete explanation, I'm really stuck there. All the documents in this area are vague. Best Regards. EDIT 1: I tried the source package of `cx_Oracle` with `python setup.py install` and `python setup.py build --compiler=mingw32` commands. I don't get the oracle error again, but I'm getting `command 'gcc' failed` error. I tried MinGW compiler and have edited environment variable `PATH` to contain MinGW install directory(e.g. `C:\MinGW`); I have also installed Microsoft Visual C++(versions 2005, 2008 and 2010); but I still get the error. EDIT 2: Since @jpmc26 mentioned about `tnsnames.ora` files, I decided to add that I have tried to make a `tnsnames.ora` and also a `sqlplus.ora` file and put them in directory `C:\oracle\instant_client_11_1\network\admin`; but as I googled I realized that if you use `cx_Oracle.connect(username, password, cx_Oracle.makedsn(ip, port, sid))` command, you can skip `.ora` files. `cx_Oracle.makedsn` would make the structure itself.