Hi Rodolfo,
> In general, could someone point me to a good reference for SQL and
> PostgreSQL commands?
On any recent PostgreSQL (8.0.0 or 7.4.6) have a look at parts II 'The
SQL Language' and VI 'Reference', especially the 'SQL Commands' chapter
of the manual (locally installed somewhere in your
/usr/share/doc/postgresql* (just a guess looking at one of your other
messages) or the online manual).
Cheers,
Alex
PS: Just a general hint: If you can include your PostgreSQL version and
operating system in your messages you make it easier to diagnose
problems and provide helpful answers.