Username and password

Each username is considered to be unique. Hence, we validate that a user

is registered by verifying the combination of the username and password.

Each and every time an action is to be performed on the database,

whether in changing or accessing user passwords, information, and

profiles, the username and password must be verified.

The username and password information needs to be built separately for

performance and implementation reasons. For performance reasons, we

need to separate the access to this information from all others to be able

to provide fast and efficient access to the data. From an implementation

point of view, we would also find it more convenient to later change

password encryption algorithms and access methods.

  User information

The user information contains information of the user's first and last

names, address, email, and so on. Once a user is registered, this

information is usually static. These data are not usually changed.

We added the date joined attribure to track when the user is registered.

  Profile information

The profile information reflects the user's interests in terms of categories

of redbooks. This list of categories of interest to the user may change

often, depending on the user. The list of categories may also change in

time.

Based on the differences of the attributes, we decide to implement these

attributes in different tables.

3.3.1.2 Orders

Orders have the following attributes:

  A username associated with the order

  The timestamp of the order

  The product that has been ordered

  A unique order identification number

This unique order ID is required, as we can no longer use username as a

unique identifier (as a user can, or should be able to, order more than one

product).

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