Function to test for Leap Years

CREATE OR REPLACE FUNCTION isLeapYear(i_year NUMBER) RETURN boolean AS

BEGIN

  -- A year is a leap year if it is evenly divisible by 4 

  -- but not if it's evenly divisible by 100 

  -- unless it's also evenly divisible by 400 

   IF mod(i_year, 400) = 0 OR ( mod(i_year, 4) = 0 AND mod(i_year, 100) != 0) THEN

      return TRUE;

   ELSE 

      return FALSE;

   END IF;

END;

/

show errors

-- Let's test it

SET SERVEROUTPUT ON

BEGIN

  IF isLeapYear(2004) THEN

     dbms_output.put_line('Yes, it is a leap year');

  ELSE

     dbms_output.put_line('No, it is not a leap year');

  END IF;

END;

/