NOT A VALID MONTH ERROR IN ORACLE FOR BELOW CODE

Question

I am getting 'not a valid month' error for the following code:

SELECT last_name, employee_id, hire_date
FROM employees
WHERE EXTRACT(YEAR FROM TO_DATE(hire_date, 'DD-MON-RR')) > 1998
ORDER BY hire_date;

Answer 1

Assuming this is the employees table from Oracle's tutorial, hire_date is already a date column. You don't need to use to_date on it:

SELECT   last_name, employee_id, hire_date
FROM     employees
WHERE    EXTRACT(YEAR FROM hire_date) > 1998
ORDER BY hire_date;