TITLE                           PUBDATE                   SYSDATE            AGE
BODYBUILD IN 10 MINUTES A DAY  | 21-JAN-01 00:00:00 | 14-NOV-12 13:16:35 | 141
REVENGE OF MICKEY              | 14-DEC-01 00:00:00 | 14-NOV-12 13:16:35 | 131
BUILDING A CAR WITH TOOTHPICKS | 18-MAR-02 00:00:00 | 14-NOV-12 13:16:35 | 127
DATABASE IMPLEMENTATION        | 04-JUN-99 00:00:00 | 14-NOV-12 13:16:35 | 161
COOKING WITH MUSHROOMS         | 28-FEB-00 00:00:00 | 14-NOV-12 13:16:35 | 152
HOLY GRAIL OF ORACLE           | 31-DEC-01 00:00:00 | 14-NOV-12 13:16:35 | 130

14 rows selected

SELECT title, TO_CHAR(ROUND(pubdate), 'DD-MON-YY HH24:MM:SS') AS pubdate,
  TO_CHAR(SYSDATE, 'DD-MON-YY HH24:MM:SS') AS "SYSDATE",
  ROUND(SYSDATE - TO_DATE(pubdate)) AS age
FROM books;

SELECT title,
       TO_CHAR(ROUND(pubdate), 'DD-MON-YY HH24:MM:SS') AS pubdate,
       TO_CHAR(SYSDATE, 'DD-MON-YY HH24:MM:SS') AS "SYSDATE",
       trunc( months_between( sysdate, pubdate )) AS age
  FROM books;