Creating proper model associations - ruby

Question

Using the ruby sequel gem, I have a small (sqlite3) database with the following schema:
db.create_table :item_types do
primary_key :id
String :name, unique: true, null: false
end
db.create_table :item_values do
primary_key :id
String :name, unique: true, null: false
end
db.create_table :items do
primary_key :id
foreign_key :type, :item_types, key: :id
foreign_key :value, :item_values, key: :id
String :name, unique: true, null: false
String :desc, null: false
end
Ideally, I'd like to be able to be able to use similar to
item = Item.first(...)
puts item.type.name, item.value.name
Reading through the association guide, it looks like I need a one_to_one association in the Item model for item_types and item_values. However, I'm not sure of the proper way to link them. Should the foreign key be passed via the key option, or is there a more appropriate method?

Answer 1

The guide illustrates setting up a one to many association with this example:
# Database schema:
# artists albums
# :id <----\ :id
# :name \----- :artist_id
# :name
class Artist < Sequel::Model
one_to_many :albums
end
class Album < Sequel::Model
many_to_one :artist
end
To be honest I have never used Sequel but from guide it seems like you should be doing something like:
class ItemType < Sequel::Model
one_to_many :items
end
class ItemValue < Sequel::Model
one_to_many :items
end
class Item < Sequel::Model
many_to_one :type, class: 'ItemType', key: 'item_type_id'
many_to_one :value, class: 'ItemValue', key: 'item_value_id'
end
Congratulations. You just ported the EAV anti-pattern to Sequel.