Re: checking if sequence exists

I tried this from pg_admin, but I get a syntax error (unexpected character)
 
IF EXISTS (SELECT 0 FROM pg_class
             WHERE relkind = 'S'
               AND oid::regclass::text = 'public.' || quote_ident('hibernate_sequence'))
  THEN
    RAISE EXCEPTION 'sequence public.% already exists!', 'hibernate_sequence
ENF IF;
 
Thanks.
From: Thara Vadakkeveedu <tharagv(at)yahoo(dot)com>
To: "pgsql-admin(at)postgresql(dot)org" <pgsql-admin(at)postgresql(dot)org>
Sent: Friday, November 15, 2013 2:30 PM
Subject: Re: [ADMIN] checking if sequence exists

How can we find out if a particular sequence exists ? The idea is to check if sequence first and if it does not exist then create it...the goal is to do this when we deploy the application war...
thanks
tg