I just don't buy it about adding a "category" field to a blog. Add the db field to production and make it defualt to null. Did you write your query to SELECT * instead of the fields you wanted? Tisk. Okay, fix that. Add the property to your back and front end. Don't paint the html if it's null. Optionally make a 'categories' table and do a join. 30 minutes of work, max.

If you're writing code where the front or back end data objects will break if you add a new db field, you're doing something wrong.