Schema

Backend Tables

Users

column name	data type	details
id	integer	not null, primary key
username	string	not null, unique, indexed
password digest	string	not null
session_token	string	not null, unique, indexed
balance	integer	not null, default: 1000
date	datetime	not null

• index on username, unique: true
• index on session_token, unique: true

Friendships

column name	data type	details
id	integer	not null, primary key
user1_id	integer	not null, foreign key, indexed
user2_id	integer	not null, foreign key, indexed

• index on user1_id
• index on user2_id
• combinations of user1_id and user2_idmust be unique

Lobbies

column name	data type	details
id	integer	not null, primary key
max_capacity	integer	not null, default 16
lobby_name	string	not null
password	string	optional
balance_limit	integer	optional
date	datetime	not null

Messages

column name	data type	details
id	integer	not null, primary key
body	string	not null
author_id	integer	not null, foreign key
chatroom_id	integer	not null, foreign key
date	datetime	not null

ChatRooms

column name	data type	details
id	integer	not null, primary key
chatroom_name	string	not null
`

User-Chatrooms

column name	data type	details
id	integer	not null, primary key
chatroom_id	integer	not null, foreign key
user_id	integer	not null, foreign key