PostgreSQL 9.1: Installing plpythonu/plpython3u (Python) in Windows

PostgreSQL 9.1: Installing plpythonu/plpython3u (Python) in Windows

Install plpython3u

If you're lucky, the following command will just work, and the Python language has been successfully installed:

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CREATE EXTENSION plpython3u;

If you encounter the following error:

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ERROR:  could not load library "C:/Program Files/PostgreSQL/9.1/lib/plpython3.dll": The specified module could not be found.

We have a little more work to do.
PostgreSQL 9.1 requires a VERY specific sub-version of the Python DLL: Python 3.2.x. (available here) Any
other version (3.1.x, 3.3.x, or otherwise) will cause the installation of plpython3u to fail. In addition, PostgreSQL 9.1 unfortunately does not appear to ship with Python 2.x support either.
If Python 3.2.x is not installed, download and install it.
Browse to your Python 3.2.x installation directory. By default, this should be something similar to: C:\Python32. From here, navigate to the DDLs directory and locate a DLL named python3.dll.
In a separate window, browse to you PostgreSQL installation directory. By default, this should be something similar to: C:\Program Files\PostgreSQL\9.1. From there, navigate into the lib directory and copy the python3.dll
from the other window into this directory. Rename the copied DLL from python3.dll topython32.dll.
Finally, attempt to run the CREATE EXTENSION command again:

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CREATE EXTENSION plpython3u;

This time, you should receive the expected result; signalling the installation was successful.

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CREATE EXTENSION

Testing Your plpython3u Extension

First, we need a stored procedure which utilizes the Python language:

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DROP FUNCTION test_fn(a integer, b integer);
CREATE OR REPLACE FUNCTION test_fn(a integer, b integer)
RETURNS text AS $$
result = object()
import pickle
return pickle.dumps({'a':a, 'b':b})
$$ LANGUAGE plpython3u

Now, let's query our new function:

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SELECT test_fn(1,2)

You should receive a response similar to the following:

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b'\x80\x03}q\x00(X\x01\x00\x00\x00aq\x01K\x01X\x01\x00\x00\x00bq\x02K\x02u.'

原地址 http://www.youlikeprogramming.com/2013/08/postgresql-9-1-installing-plpythonuplpython3u-python-in-windows/