CODEWITHSUNDEEP
ruby-on-railsforeign-keysrails-migrationsruby-on-rails-5
Fellow Stranger
Fellow Stranger

Reputation: 34103

Reference with custom name and foreign key

I'm on Rails 5 and have a User model.

I want to create a Book model, referencing the User model with the name author. I want as well to set foreign keys in the migration.

When searching an answer I have only found how to add columns in a migration, not on creating a new table. How would the below look like for create_table :books?

add_reference :books, :author, references: :users, index: true
add_foreign_key :books, :users, column: :author_id

Upvotes: 8

Views: 4733

Answers (1)

coding addicted
coding addicted

Reputation: 3430

You can use author_id:integer

Then in your User model: 

has_many :books, foreign_key: :author_id, class_name: "Book", dependent: :nullify

I use dependent: :nullify to avoid errors when you delete a record, but you can use dependent: :destroy if you need to destroy the books when you destroy the user.

And Book model:

belongs_to :user, foreign_key: :author_id, class_name: 'User'

You should add an index on this column.

Upvotes: 6

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