Is it possible to make a custom field that lists true or false if another date column is less then the sysdate?

Create a read-only custom field that uses a similar SQL statement as below, I just picked revised_due_date as an example.  Just define the bind variables in the SQL arguments to complete the set up.

SELECT 
   CASE WHEN (revised_due_date < SYSDATE) THEN
      'TRUE'
   ELSE
      'FALSE'
   END
FROM SHOP_ORD
WHERE order_no = :order_no
AND release_no = :release_no
AND sequence_no = :sequence_no