Nested Attributes example

sequel.rb

require 'sequel'
require 'sqlite3'

DB = Sequel.sqlite

DB.instance_eval do
  create_table :artists do
    primary_key :id
    String      :name
  end
  
  create_table :albums do
    primary_key :id
    foreign_key :artist_id
    String      :name
  end
end

class Artist < Sequel::Model
  one_to_many :albums
  
  plugin :nested_attributes
  nested_attributes :albums, destroy: true
end

class Album < Sequel::Model
  many_to_one :album
end

a = Artist.new name: 'YJM'

a.albums_attributes = [ { name: 'RF' }, { name: 'MO' } ]

a.save

a.update albums_attributes: [ { id: 1, name: 'T' } ]

a.update albums_attributes: [ { id: 1, _delete: true } ]

a.albums # => [#<Album @values={:id=>1, :artist_id=>1, :name=>"T"}>, #<Album @values={:id=>2, :artist_id=>1, :name=>"MO"}>]
a.refresh
a.albums # => [#<Album @values={:id=>2, :artist_id=>1, :name=>"MO"}>]