how to get object by created date in active android?

i have many objects , i want to get only the first created so i need to order my db by created date and limit the search for 1 result .

and in general how can i know what are the order string available ?

this is my current code :

   List<Report> reports;

    reports = new Select()
                .from(Report.class)
                .execute();

i know there is an option to add order in this method but i don't know how to use it for my needs .