Joe,
> I am also new to Postgresql though not ORDBMS systems ... why should
> you not
> use OIDs as a primary key in Postgresql?
1. OIDs are not normally backed up, and it requires special pg_dump
options to backup and restore them, and there can be problems in this
process.
2. If you have a very large database with a lot of activity, the OID
counter will "roll over" which is not a problem for the system, but
will be for any OID-based primary keys.
3. It's not great design to make a column which is normally hidden in
queries your primary key.
-Josh Berkus