comp.lang.python

Brad Harms

2/23/2010 6:59:00 AM

On Mon, 22 Feb 2010 09:10:38 -0800, Alex Quinn wrote:

> Is there a way to have some kind of database (i.e. sqlite3, bsddb, dbm,
> etc.) that works out of the box on any Win/Linux/Mac machine with Python
> 2.6+ or 3.x? It's okay if the file format is different between machines,
> but I want my script to work without having to install anything.
>
> Problems with current modules:
>
> * Shelve used to do this. Unfortunately, since bsddb was
> deprecated/removed from the standard distro and Windows doesn't have dbm
> or gdbm, the only remaining option on Windows is dumbdbm, which is
> discouraged in the docs.
>
> * Sqlite3 should fill the void now. However, in my experience, nearly
> every Linux Python install I encounter has a broken sqlite3 module
> ("ImportError: No module named _sqlite3"). It's a well-documented issue,
> but it the solution generally requires root access, which I don't have
> on these servers.
>
> Potential solutions:
>
> * Could I somehow bundle with my project the _sqlite3.so file and/or
> whatever else it needs? Or is there an alternate sqlite3 module I could
> use as a fallback that would just interface with the sqlite3 executable
> on the machine (i.e. /usr/local/bin/sqlite3)?
>
> * Is there a way to drop bsddb into my project so it works out of the
> gate (no install) on either Linux, Windows, or Mac?
>
> If you have any ideas, I'd be most appreciative. My objective here is
> just to find a portable and reliable solution that I can use for small
> projects.
>
> Thanks,
> Alex

Hi,

I'm speaking with little experience here, but one thought I had is to try
compiling Pysqlite ( http://pypi.python.org/pypi/pysq... ) for
each of your target OS's, probably using GCC cross compilers for the
platforms you aren't compiling on, then sort of "splice" them together so
that _sqlite3 always points to the binary for the current OS.

This snippet might help you get started:

import sys

# Linux binary
if 'linux' in sys.platform.lower():
import _sqlite3_linux as _sqlite3

# Windows binary
elif 'win32' == sys.platform:
import _sqlite3_windows as _sqlite3

# Mac binary
elif 'darwin' == sys.platform:
import _sqlite3_mac as _sqlite3

sys.modules['_sqlite3'] = _sqlite3


I'm not exactly sure when you would run this code. It would have to be
sometime before you import the main sqlite3 module.

--
Brad Harms -- http://al...