Re: SOLVED: help! - how to get postgres 7.3 back

[Richard Lyons <richard@the-place.net>]

On Saturday 10 January 2004 01:08, Oliver Elphick wrote:

[...snipped: details of stupidly upgrading postgres 
    without first doing pg_dumpall, causing need to
    downgrade from 7.4 to 7.3 temporarily...]
    
> Use --force-depends and --force-conflicts.
>

Just in case it helps the anyone else as absent minded as me, this is 
what I did, following Oliver's advice:

(as root)
mkdir ~/postgres_temp                          ; save database
cp -R /var/lib/postgres/data ~/postgres_temp/  ; just in case...
cd {wherever/the/postgres7.3/debs/are}
dpkg --force-conflicts --force downgrade --force-depends -i *.deb
rm -R /var/lib/postgres/dumpall/7.3            ; actually I moved it
                                               ; being ultracautious.
/etc/init.d/postgresql start                   ; Monique suggested
                                               ; using invoke-rc.d
                                               ; but it silently 
                                               ; did nothing
su postgres
/usr/lib/postgresql/bin/pg_dumpall \ 
    > /var/lib/postgres/dumpall/7.3/db.out     ; dunno why pg_dumpall
                                               ; isn't on path

Then used aptitude to update and manually selected 7.4 in each
of postgresql and postgresql-client.  I expected it to do this 
automatically, but it didn't.  That installed 7.4 and the postinstall 
successfully upgraded the database.  I didn't have to manually load the 
dump.

While doing that, I was checking the man page and found that, 
apparently, I could have avoided the whole operation by using
'pg_dumpall -i' - it says this ignores version mismatch.  Obviously, I 
haven't tried it, but it should be the easier way to upgrade the 
database.  I'll have to try it next time I mess up...

HTH
-- 
richard