Book database

The book database is accessed through the Bdb class. It's a sqlite3 database accessed using Python's sqlite3 library. The syntax for the queries is all standard SQL and so it would be easy for somebody to make it support another SQL database system.

Primary Key

The primary key, as of 0.9, will be autogenerated by the database as opposed to by python. This should be more efficient and less error-prone. Unfortunately, there's a 1 in 9 quintillion chance that, when the user is entering a barcode, it could hit one already in use and generate an error.

More to come later