Migrating databases...

I'm posting to c.d.p.general, rather than to novices or questions, because I'm
using google and it's the only one for which I'm registered.

I'm having difficulty because the situation is not straightforward, and I can't
seem to sort out what has to be done.  So I'd appreciate it if someone would
provide a step by step procedure for me.

I'm running Mandrake 8.2, which has postgresql-7.2.1.  It is installed and is
started at boot.  I have a small database that I developed when I ran 8.0,
which had postgresql-7.0.3.  The 8.0 installation is damaged, such that no users
are accepted, and so I can't run the 7.0.3 version there to dump the database.

So I got the source for 7.0.3 and installed it in 8.2 at the /usr/local level.
All the files are where they are supposed to be, and I'm ready to get the thing
running so I can dump the database (copied over to $HOME in 8.2 from the 8.0
installation).

I read that I can have both versions running in parallel, and that there is a
simple command line that will make the database conversion.  Unfortunately,
I don't know how to start the 7.0.3 without invoking the 7.2.1.  I'm willing
to start over if necessary ('gmake uninstall && gmake clean && ./configure &&
gmake && gmake install', or so I would imagine).

So you see, I'm not exactly upgrading the database with a new installation here,
but rather (re)installing the old version, hopefully providing it with the data
base to dump, and then restoring it to the already installed new version.  And I
am unable to see clearly how to proceed.

I'd be appreciative and thankful for some help here!

Bill Tallman