Re: Considerations for running current cvs pgsql and pgsql release on same machine?

"Robert B. Easter" <reaster@comptechnews.com> writes:
> I'm wanting to run pgsql 7.0.3 release and pgsql current cvs on the same 
> machine without them conflicting (if possible).  Can someone explain what I 
> should look out for when trying to do this?

I routinely run multiple versions at the same time.  You need a separate
port, install directory, and data directory for each.  Easiest way to do
this is to configure the non-default versions with

./configure --with-pgport=nnn --prefix=/path/to/someplace

to establish their ports and install dirs, and then initdb each version
with the appropriate data directory specified.  A user then doesn't have
to do much except make his PATH point at the PREFIX/bin dir for the
version he wants to use at the moment.

You may also find that you have to pump up your kernel's IPC resource
parameters in order to start up multiple postmasters.

> How will the use of the environment variables PGDATA and PGLIB be
> affected if I have them still pointing at the release version?

They had better have the right values while initdb'ing or starting
each individual version.  There's no good reason to have either one
set in the general environment, or actually to set them at all --- you
can get the same results with command line switches to initdb and
postmaster, with much less chance of bad side-effects.

A tip I find handy is to make sure that the databases available under
each live postmaster have distinct names.  This helps to avoid the
mistake of testing against 7.0.2 when you thought you were testing
against 7.0.3 or current or whatever...

> I've been following this list long enough and still 
> enjoy it so I want to try towards contributing stuff.

Welcome aboard!
        regards, tom lane