I don't have time for a full tutorial, but here is how I managed, after weeks of trying without luck, to get Psycopg2 to work with Python 2.7.3 and PostgreSQL 9.2 on Mac OS 10.8, Mountain Lion.
The problem I was having, after installing Psycopg using python setup.py install was related to this error when running import psycopg2 from a Python shell. Symbol not found: _PQbackendPID.
This fixed it:
- You'll need XCode from the App Store and the Command Line Tools (Google it if this sounds like gibberish).
- Follow the instructions about exporting your path here: http://www.jonathandean.com/2011/08/postgresql-8-4-on-mac-os-x-10-7-lion/. This will make your Postgresql 9.2 the default. You can check if it already is by typing which psql in a Terminal window.
- Create a Universal libpq.dylib following instructions here: http://contestclash.blogspot.com/2009/09/building-psycopg2-on-snow-leopard.html. Copy the new file to wherever your Postgresql is. In my case it was /Library/PostgreSQL/9.2/lib. These instructions solved the 64/32 bit architecture problem. (This crucial piece of info was burried in Google and took quite a while to find. All other solutions suggested running Python in 32 bit mode, which didn't work).
- Modify the psycopg2 setup.cfg file following these instructions (only the last part, right after "Change setup.cfg so it looks like the following:"): http://blog.timc3.com/2010/08/20/psycopg2-os-x-_pqbackendpid/.
- Create the simlinks mentioned in the comments here in order to fix a new problem with SSL and Crypto libraries: http://psycopg.lighthouseapp.com/projects/62710/tickets/111-library-not-loaded-libssl100dylib
- Now build psycopg2 using "python setup.py install".
- You should be able to import psycopg2 from a Python shell or from IDLE (I actually did it for EPD free).
Many, many thanks to each of the four sources cited in steps 2-6. You did all the work. All I needed to do was find which instructions to follow.
I hope this helps others struggling with this issue.