Database Design

Chatter-jee Database is in Microsoft Access 97 format.It's accessed by the Server and accompanying DLL (User.dll) using ODBC (Open Database Connectivity).

The database has only 3 tables:

  1. User- Contains all the user ids and their passwords
  2. Friends - Contains information about who is who's friend.
  3. BlockedUser - Contains information about who has blocked whom.

The table design is as follows:

User

Column Name Data Type Width Constraints
UserName Text 15 Primary Key
Password Text 15 Required

Friends (Relations Table)

Column Name Constraints
UserName Primary Key1
Foreign Key from User table
FriendName Primary Key2
Foreign Key from User table

Blocked User(Relations Table)

Column Name Constraints
UserName Primary Key1
Foreign Key from User table
BlockedUserName Primary Key2
Foreign Key from User table

The following figure shows the relationships and dependencies between tables: