In the book, which I purchased and have enjoyed so far, I am wondering why you need to have a guid and is there a way to program without this? Is this something that is unique to SQL Server 2005 or Express? I only use ACCESS at the the moment. Thanks.

Using a GUID instead of a sequential number helps to prepare your database in several ways for future expansion. First, using a sequential number you need to be concerned with two users inserting a record simultaneously and causing a conflict because the users are using the same number. You’ll have to code to handle this. Next, if you ever upgrade your database from Access to SQL Server and then need to replicate your database you’ll need to use a GUID to uniquely identify each row.

Access does support GUIDs as outlined in Chapter 1 but you are free to use a sequential number instead.

Thearon