Michael Glaesemann <grzm(at)myrealbox(dot)com> writes:
> [about a second installation on an existing machine]
> When initializing the database cluster, I need to create an
> environmental variable (such as PGDATA2) set to the directory where the
> data will be stored.
No, you'd just set PGDATA.
Joe Conway just posted some cleaned-up scripts for working with multiple
installations on-the-fly:
http://archives.postgresql.org/pgsql-patches/2003-11/msg00318.php
This might be overkill for your needs, but I can attest that it covers
all the essential bases.
regards, tom lane