## ### Documentation

Schema

Users

Column Name	Data Type	Details	index?
id	integer	not null, primary key	yes
username	string	not null, unique	yes
email	string	not null, unique	yes
password_digest	string	not null	no
session_token	string	not null, unique	yes
album_id	integer	not null, foreign key for albums purchased by a user, unique	yes
created_at	timestamp	not null	no
updated_at	timestamp	not null	no

• index on username, unique: true
• index on email, unique: true`
• index on session_token, unique: true
• album_id references albums

Artists

Column Name	Data Type	Details	index?
id	integer	not null, primary key	yes
name	string	not null, name of artist, unique	yes
location	string	not null, where artist is based	no

• index on title, unique: true

Albums

Column Name	Data Type	Details	index?
id	integer	not null, primary key	yes
title	string	not null, name of the album	no
description	string	album description, supplied by artist/label	no
credits	string	album credits	no
artist_id	integer	not null, foreign key for artist that released the album	yes
created_at	timestamp	---	yes
updated_at	timestamp	---	yes

• index on artist_id
• artist_id references artists

Tracks

Column Name	Data Type	Details	index?
id	integer	not null, primary key	yes
title	string	not null, name of the track	no
track_number	integer	not null, position of track w/r/t the album, unique	no
artist_id	integer	not null, foreign key for artist that released the track	yes
album_id	integer	not null, foreign key for album track belongs to	yes
created_at	timestamp	---	yes
updated_at	timestamp	---	yes

• index on artist_id
• artist_id references artists
• index on album_id
• album_id references albums

Cart Items

Column Name	Data Type	Details	Index?
id	integer	not null, primary key	yes
user_id	integer	not null, user cart belongs to	yes
album_id	integer	album in the user's cart, unique	yes
created_at	timestamp	---	no
updated_at	timestamp	---	no

• index on user_id
• user_id references users
• index on album_id
• album_id references albums

Active Storage Attachments

Column Name	Data Type	Details	Index?
name	string	not null	no
record_type	integer	not null	yes
record_id	integer	not null	yes
blob_id	integer	not null	no
created_at	timestamp	---	no

• index on blob_id
• blob_id references Active Storage Blobs
• index on record_type
• index on record_id
• index on name

Active Storage Blobs

Column Name	Data Type	Details	Index?
key	string	not null	yes
filename	string	not null	no
content_type	string	not null	no
metadata	text	---	no
byte_size	bigint	---	no
checksum	string	---	no
created_at	datetime	---	no

• index on key