Different date format

From: Erika Grondzakova <Erika.Grondzakova_at_cern.ch>
Date: Fri, 04 May 2001 14:43:27 +0200
Message-ID: <3AF2A3EF.FF2AFAE2@cern.ch>

Hello,

Connected to:
Oracle8i Enterprise Edition Release 8.1.7.0.0 - Production With the Partitioning option
JServer Release 8.1.7.0.0 - Production

Why do I get a different output for following selects?

SQL> alter session set nls_date_format='DD-MON-YY';

Session altered.

SQL> select add_months(to_date(sysdate, 'DD-MON-YYYY'), -299) from dual;

ADD_MONTH

---

04-JUN-24 SQL> select add_months(sysdate, -299) from dual;

ADD_MONTH

---

04-JUN-76 For the session date format 'DD-MON-YYYY' I get a correct output...

SQL> alter session set nls_date_format = 'DD-MON-YYYY';

Session altered.

SQL> select add_months(to_date(sysdate, 'DD-MON-YYYY'), -299) from dual;

ADD_MONTHS(

---

04-JUN-1976 SQL> select add_months(sysdate, -299) from dual;

ADD_MONTHS(

---

04-JUN-1976 Thank you in advance,

Erika Received on Fri May 04 2001 - 07:43:27 CDT