CREATE TABLE my_dates
(my_date DATE, my_month VARCHAR2(10), my_day VARCHAR2(10), cntr INTEGER);

INSERT INTO my_dates (my_date, my_month, my_day, cntr)
SELECT
TRUNC(sysdate,'YYYY')+ROWNUM -1,
TO_CHAR(TRUNC(sysdate,'YYYY')+ROWNUM -1,'MONTH'),
TO_CHAR(TRUNC(sysdate,'YYYY')+ROWNUM -1,'DD'),
ROWNUM
FROM all_objects
WHERE TRUNC(sysdate,'YYYY')+ROWNUM -1 < ADD_MONTHS(TRUNC(sysdate,'YYYY'),12);