What Remains?

The SqlPayrollDatabase class can save new Employee objects and load Employee objects. But it's not complete. What would happen if we save an Employee object that was already saved in the database? This still needs to be handled. Also, we haven't done anything about time cards, sales receipts, or union affiliations. Based on the work that we've accomplished so far, adding this functionality should be fairly straightforward and is, again, left to you.