New user questions

I'm running PostgreSQL 8.0.3, the latest stable ebuild, on Gentoo linux.

1) Am I inviting any problems in linux by moving the directory
/var/lib/postgresql to /home/postgresql, and then symlinking
/home/postgresql back to /var/lib/postgresql? The reason for this is
to avoid having databases, indexes, etc, physically ending up on my
/dev/sda1 partition, which I want to reserve for the OS only.

2) Although I have an AMD64 cpu. I chickened out and went for a 32-bit
install. If/when I do migrate to 64-bit, can I keep my databases, or
will I have to export/import them?

3) Are there any free sample datasets and tutorials for users who are
familiar with SQL and Oracle PL/SQL? I have no DBA experience, but I do
write quite a few read-only Oracle SQL queries and PL/SQL programs at
work, even though I'm not a CS. An Oracle-to-PostgreSQL comparison
would be nice to see.

--
Walter Dnes <waltdnes(at)waltdnes(dot)org> In linux /sbin/init is Job #1
My musings on technology and security at http://tech_sec.blog.ca