Postgres Database Schema

users

column name	data type	details
id	integer	not null, primary key
username	string	not null, indexed, unique
email	string	not null, indexed, unique
password_digest	string	not null
session_token	string	not null, indexed, unique
profile_picture_id	integer	not null
status	string
title	string
created_at	datetime	not null
updated_at	datetime	not null

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

messages

column name	data type	details
id	string	not null
user_id	integer	not null, foreign key, indexed
messageable_id	integer	not null, foreign key, indexed
messageable_type	string	not null, foreign key, indexed
parent_message_id	integer	foreign key, indexed
body	string	not null
created_at	datetime	not null
updated_at	datetime	not null

• index on author_id
• index on parent_message_id
• author_id references users
• parent_message_id references messages
• [:messageable_id, :messageable_type], unique: true polymorphically references either channels or direct_messages

channels

column name	data type	details
id	integer	not null, primary key
name	string	not null
description	string
private	boolean
admin_id	integer
created_at	datetime	not null
updated_at	datetime	not null

memberships

column name	data type	details
id	integer	not null, primary key
user_id	integer	not null, foreign key, indexed
memberable_id	integer	not null, foreign key, indexed
memberable_type	string	not null, foreign key, indexed
created_at	datetime	not null
updated_at	datetime	not null

• user_id references users
• [:memberable_id, :memberable_type], unique: true polymorphically references either channels or direct_messages

direct_messages

column name	data type	details
id	integer	not null, primary key
created_at	datetime	not null
updated_at	datetime	not null

profile_pictures

column name	data type	details
id	integer	not null, primary key
url	string	not null
user_id	integer	not null, indexed, foreign key

• user_id references users