Re: Unable to run psql on 9.5 after broken 12 remove

After upgrading python the InvalidUrl is gone, but I still can't run psql

Output of pg_lsclusters, if needed
root(at)datastore-1:/usr/share/postgresql-common# pg_lsclusters
Ver Cluster Port Status                Owner     Data
directory               Log file
9.5 main    6543 online                postgres
/var/lib/postgresql/9.5/main /var/log/postgresql/postgresql-9.5-main.log
12  main    5432 down,binaries_missing <unknown>
/var/lib/postgresql/12/main /var/log/postgresql/postgresql-12-main.log

I followed
https://askubuntu.com/questions/1223270/psql-command-error-postgresql-version-12-is-not-installed
with no luck, apt-purge simply states that pg12 is not installed.

Il 03/07/2020 10:37, Moreno Andreo ha scritto:
> I have a production server running pg9.5 seamlessly.
> Yesterday I decided to install libpq to have some crypto functions.
> Unexpectedly, it installed postgresql 12 and its libpq.
> I don't need pg 12, so I decided to remove it.
> It did not went well
>
> root(at)datastore-1:/home/user# apt-get --purge remove postgresql-client-12
> Reading package lists... Done
> Building dependency tree
> Reading state information... Done
> The following package was automatically installed and is no longer
> required:
>   libuuid-perl
> Use 'apt-get autoremove' to remove it.
> The following packages will be REMOVED:
>   postgresql-12* postgresql-client-12* postgresql-contrib*
> 0 upgraded, 0 newly installed, 3 to remove and 89 not upgraded.
> 1 not fully installed or removed.
> After this operation, 30.9 MB disk space will be freed.
> Do you want to continue? [Y/n] y
> (Reading database ... 32065 files and directories currently installed.)
> Removing postgresql-contrib (12+215.pgdg80+1) ...
> Removing postgresql-12 (12.3-1.pgdg80+1) ...
> update-alternatives: using
> /usr/share/postgresql/9.5/man/man1/postmaster.1.gz to provide
> /usr/share/man/man1/postmaster.1.gz (postmaster.1.gz) in auto mode
> Purging configuration files for postgresql-12 (12.3-1.pgdg80+1) ...
> Removing postgresql-client-12 (12.3-1.pgdg80+1) ...
> update-alternatives: using
> /usr/share/postgresql/9.5/man/man1/psql.1.gz to provide
> /usr/share/man/man1/psql.1.gz (psql.1.gz) in auto mode
> Processing triggers for postgresql-common (215.pgdg80+1) ...
> Building PostgreSQL dictionaries from installed myspell/hunspell
> packages...
> Removing obsolete dictionary files:
> Setting up python3.4 (3.4.2-1+deb8u3) ...
>   File "/usr/lib/python3.4/http/client.py", line 1014
>     raise InvalidURL(f"URL can't contain control characters. {url!r} "
> ^
> SyntaxError: invalid syntax
> dpkg: error processing package python3.4 (--configure):
>  subprocess installed post-installation script returned error exit
> status 1
> Errors were encountered while processing:
>  python3.4
> E: Sub-process /usr/bin/dpkg returned an error code (1)
>
> After this, the package is not anymore on the installed list and I'm
> not able to issue the psql command:
>
> root(at)datastore-1:/home/user# sudo -u postgres psql
> Error: PostgreSQL version 12 is not installed
>
> How can I repair this?
> Thanks in advance
> Moreno.
>
>
>