SET HEADING OFF not working

From: <p.pandey003_at_gmail.com>
Date: Thu, 14 Nov 2013 00:55:30 -0800 (PST)
Message-ID: <a87d3815-74a5-42fc-a9b7-a444f95a860b_at_googlegroups.com>


ALL, below is the output.

SQL> select UPN_SUFFIX from usage_partition where substr(UPN_FROM,1,10) >= to_char(sysdate-9,'YYYY-MM-DD') and substr(UPN_FROM,1,10) <= to_char(sysdate-1,'YYYY-MM-DD');
_013
_014
_015
_016
_017
_018
_019
_020
_021

SQL> spool off;

Please help to fix it. Need in urgency. Received on Thu Nov 14 2013 - 09:55:30 CET

Original text of this message