[SQL] Desc Commnad in pgsql?

[VG]

Hello All,

I like to know how can I achieve the same functionality that is give by desc
commnad in mysql or oracle.
Also specify me the book related to pgsql as a beginner.
Presently my task is going to be communication of ruby with pgsql

Thanks in advanced.

Vikas

[SQL] psql: FATAL: Ident authentication failed for user "postgres"

[VG]

Hi,

I have installed postgresql-serve using yum
hba.conf group and owner were postgres then i changed it to root.

when i type psql -U postgres command ( as root  user) I get:

psql: FATAL:  Ident authentication failed for user "postgres"

My file permission are:
drwx-- 5 postgres postgres  4096 2008-09-06 00:36 base
drwx-- 2 postgres postgres  4096 2008-09-08 21:44 global
drwx-- 2 postgres postgres  4096 2008-09-06 00:36 pg_clog
-rw-r--r-- 1 postgres postgres  3200 2008-09-08 21:35 pg_hba.conf
-rw--- 1 postgres postgres  1460 2008-09-06 00:36 pg_ident.conf
drwx-- 2 postgres postgres  4096 2008-09-08 15:52 pg_log
drwx-- 4 postgres postgres  4096 2008-09-06 00:36 pg_multixact
drwx-- 2 postgres postgres  4096 2008-09-06 00:36 pg_subtrans
drwx-- 2 postgres postgres  4096 2008-09-06 00:36 pg_tblspc
drwx-- 2 postgres postgres  4096 2008-09-06 00:36 pg_twophase
-rw--- 1 postgres postgres 4 2008-09-06 00:36 PG_VERSION
drwx-- 3 postgres postgres  4096 2008-09-06 00:36 pg_xlog
-rw--- 1 postgres postgres 15336 2008-09-06 00:36 postgresql.conf
-rw--- 1 postgres postgres49 2008-09-08 21:44 postmaster.opts
-rw--- 1 postgres postgres46 2008-09-08 21:44 postmaster.pid

How could i achieve this..
Regards,
Vikas