Why the query returns results having hire_date greater than given date?

[itiger]

SELECT last_name, TO_CHAR(hire_date, 'DD-Mon-yyyy')
from employees
WHERE TO_DATE(hire_date, 'DD-Mon-YYYY') < '01-Jan-1990';


Output:

LAST_NAME       TO_CHAR(HIRE_DATE,'DD-MON-YYYY')
-------------------------------------------------- 
King            17-Jun-1987 
Kochhar         21-Sep-1989 
De Haan         13-Jan-1993 
Hunold          03-Jan-1990 
Ernst           21-May-1991 
Austin          25-Jun-1997

Why the query returns rows of those employees having hire_date greater (after) '01-Jan-1990'.

[amitpatel66]

Try this:

SELECT last_name, TO_CHAR(hire_date, 'DD-Mon-yyyy') 
from employees 
WHERE TO_DATE(hire_date, 'DD-Mon-YYYY') < 
TO_DATE('01-Jan-1990','DD-Mon-RRRR');
/