Music Store

// music-store: iTunes-like digital music store adapted from Chinook
// Source: https://github.com/lerocha/chinook-database (MIT License)
// Money fields stored as i64 cents (e.g. unit_price 99 = $0.99).

Genre {
  id: +uuid
  name: &string @length(1, 120)
  tracks: [Track]
  created_at: +timestamp
}

MediaType {
  id: +uuid
  name: &string @length(1, 120)
  tracks: [Track]
  created_at: +timestamp
}

Artist {
  id: +uuid
  name: &string @length(1, 120)
  albums: [Album]
  created_at: +timestamp
}

Album {
  id: +uuid
  title: string @length(1, 160)
  artist: *Artist
  tracks: [Track]
  created_at: +timestamp
}

Track {
  id: +uuid
  name: string @length(1, 200)
  album: ?Album
  media_type: *MediaType
  genre: ?Genre
  composer: string?
  milliseconds: i32 @min(0)
  bytes: i32? @min(0)
  unit_price: i64 @min(0)
  playlists: [Playlist]
  invoice_lines: [InvoiceLine]
  created_at: +timestamp
}

// Playlist<->Track many-to-many: bidirectional [Track]/[Playlist] with no payload.
// (Chinook's PlaylistTrack join table carries only the composite PK.)
Playlist {
  id: +uuid
  name: string @length(1, 120)
  tracks: [Track]
  created_at: +timestamp
}

// Self-referencing employee org chart via reports_to.
// support_rep on Customer points here (optional -- not all customers have a rep).
Employee {
  id: +uuid
  last_name: string @length(1, 80)
  first_name: string @length(1, 80)
  title: string?
  reports_to: ?Employee
  birth_date: timestamp?
  hire_date: timestamp?
  address: string?
  city: string?
  state: string?
  country: string?
  postal_code: string?
  phone: string?
  fax: string?
  email: &string @email
  subordinates: [Employee]
  supported_customers: [Customer]
  created_at: +timestamp
  updated_at: timestamp?
}

Customer {
  id: +uuid
  first_name: string @length(1, 80)
  last_name: string @length(1, 80)
  company: string?
  address: string?
  city: string?
  state: string?
  country: string?
  postal_code: string?
  phone: string?
  fax: string?
  email: &string @email
  support_rep: ?Employee
  invoices: [Invoice]
  created_at: +timestamp
  updated_at: timestamp?
  @soft_delete
}

Invoice {
  id: +uuid
  customer: *Customer
  invoice_date: timestamp
  billing_address: string?
  billing_city: string?
  billing_state: string?
  billing_country: string?
  billing_postal_code: string?
  total: i64 @min(0)
  lines: [InvoiceLine]
  created_at: +timestamp

  @index(customer, invoice_date)
}

InvoiceLine {
  id: +uuid
  invoice: *Invoice
  track: *Track
  unit_price: i64 @min(0)
  quantity: i32 @min(1)
  created_at: +timestamp

  @index(invoice, track)
}