Re: libpython - cannot open shared object file

On 06/22/2010 09:52 AM, Tom Wilcox wrote:
> Hi,
>
> Can anyone help me get up and running on Ubuntu 64-bit Server (lucid) OS
> with PostgreSQL 64-bit and Python 2.6?
>
> (Please note that this is all running in a VirtualBox VM however I am
> not convinced that is relevant here)
>
> I have a load of functions written in plpythonu and I can't run anything
> until they are able to run. Please help.. I have been through set up
> using the Ubuntu Software Manager (postgresql, postgresql-8.4, plpython
> for postgresql-8.4,..), I have tried using sudo apt-get install
> postgresql-8.4, I have downloaded and installed using the 64-bit linux
> binary from postgresql.com.
>
> In all cases, I have started the server from "su postgres" in bash.. it
> happily runs and pgadmin3 can connect. I successfully create my
> plpythonu and pgsql functions then I attempt to use them in a simple
> SELECT statement (see below) and the resulting error occurs:
>
> --------------
>
> DROP LANGUAGE IF EXISTS plpythonu CASCADE;
> CREATE LANGUAGE plpythonu;
>
> CREATE OR REPLACE FUNCTION min_float(a float, b float) RETURNS float AS $$
> return min(a,b);
> $$ LANGUAGE plpythonu;
>
> SELECT min_float(1,2);
>
> --------------
>
> ERROR: could not load library
> "/opt/PostgreSQL/8.4/lib/postgresql/plpython.so": libpython2.3.so.1.0:
> cannot open shared object file: No such file or directory
>
> ----------------
>
> I don't know enough to know where to start with this..
>
> I have python2.6 installed. The following find command results:
>
> root(at)ubuntu64-bertha:/opt/PostgreSQL/8.4/lib# find /* -name libpython*
> find: '/media/windows-share/System Volume Information': Operation not
> permitted
> /opt/PostgreSQL/8.4/lib/postgresql/libpython2.6.so.1
> /usr/lib/gnome-vfs-2.0/modules/libpythonmethod.so
> /usr/lib/gnome-vfs-2.0/modules/libpythonmethod-2.6.so
> <http://libpythonmethod-2.6.so>
> /usr/lib/python2.6/config/libpython2.6.so <http://libpython2.6.so>
> /usr/lib/libpython2.6.so.1
> /usr/lib/libpython2.6.so.1.0
> /usr/lib/gedit-2/plugin-loaders/libpythonloader.so
> /usr/share/doc/libpython2.6
> /usr/share/lintian/overrides/libpython2.6
> /var/lib/dpkg/info/libpython2.6.symbols
> /var/lib/dpkg/info/libpython2.6.shlibs
> /var/lib/dpkg/info/libpython2.6.md5sums
> /var/lib/dpkg/info/libpython2.6.postrm
> /var/lib/dpkg/info/libpython2.6.postinst
> /var/lib/dpkg/info/libpython2.6.list
>
> I tried creating a symbolic link that points to the libpython2.6 like so:
>
> root(at)ubuntu64-bertha:/opt/PostgreSQL/8.4/lib# ln -s
> ./postgresql/libpython2.6.so.1 libpython2.3.so.1.0
>
> but then it gave me this error instead:
>
> ERROR: could not load library
> "/opt/PostgreSQL/8.4/lib/postgresql/plpython.so":
> /opt/PostgreSQL/8.4/lib/postgresql/plpython.so: undefined symbol:
> Py_InitModule4
> SQL state: 58P01
>
> So I presume it was expecting a different python version..(I have now
> removed that symbolic link so I am back to my original error).
>
> I am losing this battle badly and I am desperately running out of time.
> Please can anyone help me or suggest anything I can try to sort this out
> and get plpython running my functions in postgresql on this linux OS.
>
> Please help me!
>
> Tom
>

To start narrowing this down.
What installation of Postgres are you running now(you mention several)?
It seems pl/python is compiled against Python 2.3. Have you been running
Python 2.3?

--
Adrian Klaver
adrian(dot)klaver(at)gmail(dot)com