How to make Active Record associations work without creating a foreign_key?

Question

I want an item to be able to get an associated record from ItemType table:

item = Item.first item.item_type # <--- ERROR

But I get an error:

SELECT "item_types".* FROM "item_types" WHERE "item_types"."item_id" = ? LIMIT 1 [[nil, 11]] SQLite3::SQLException: no such column: item_types.item_id: SELECT "item_types".* FROM "item_types" WHERE "item_types"."item_id" = ? LIMIT 1 ActiveRecord::StatementInvalid: SQLite3::SQLException: no such column: item_types.item_id: SELECT "item_types".* FROM "item_types" WHERE "item_types"."item_id" = ? LIMIT 1

From error I can see that ActiveModel tries to access item_id column. But I do not want to create an item_id column inside my ItemType table... It is an enumeration table with types of items such as:

#id|name 1|"Task" 2|"User Story" 3|"Bug" 4|"Feature Request"

Item model

# # Table name: items # # id :integer not null, primary key # name :string # created_at :datetime not null # updated_at :datetime not null # item_type_id :integer # class Item < ActiveRecord::Base has_one :item_type end

ItemType model

# == Schema Information # # Table name: item_types # # id :integer not null, primary key # name :string # created_at :datetime not null # updated_at :datetime not null # class ItemType < ActiveRecord::Base end

zwippie · Accepted Answer · 2015-05-07 12:01:57Z

2

You have only defined the relationship in model Item but you have to define it in model ItemType too:

class ItemType < ActiveRecord::Base has_many :items end

answered May 7, 2015 at 12:01

zwippie

15.6k3 gold badges44 silver badges58 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

yaru Over a year ago

It did not help. I still get this error: SELECT "item_types".* FROM "item_types" WHERE "item_types"."item_id" = ? LIMIT 1 [[nil, 21]] SQLite3::SQLException: no such column: item_types.item_id: SELECT "item_types".* FROM "item_types" WHERE "item_types"."item_id" = ? LIMIT 1 ActiveRecord::StatementInvalid: SQLite3::SQLException: no such column: item_types.item_id: SELECT "item_types".* FROM "item_types" WHERE "item_types"."item_id" = ? LIMIT 1

zwippie Over a year ago

What if you change the relation in the Item model to: belongs_to :item_type?

Collectives™ on Stack Overflow

How to make Active Record associations work without creating a foreign_key?

1 Answer 1

2 Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Related