IN THIS CHAPTER
If Web sites had to deal with only the here and now, developing them would be a much easier undertaking. Alas, most sites need to also remember what has happened in the past and must be able to access that information in the future—that's persistence.
In this chapter, you'll see how to store data in the database so that it can be restored at a future time. This becomes critical when you want to be able to deal with a user session that times out, leaving unfinished business, but that is also at the core of other types of persistence, such as recording orders or updating user information.