Rails: How to use BIGINT as Primary Key

Question

I've read through a lot of articles discussing how to use BIGINT as primary keys in Rails, but it seems like all of them are outdated.

How can I use BIGINT's for my primary keys, preferrably by just setting this globally. (i am aware of the differences in performance)

Things I've tried:

• http://www.mccartie.com/2016/12/05/rails-5.1.html
• https://moeffju.net/blog/bigints-in-rails-as-primary-keys
• and a lot more I cannot remember

Answer 1

If your app was natively built in rails '>= 5.1', your primary keys should already be BIGINT. By "natively built" I mean that your migrations were initially run with that Rails version (as opposed to running them in < 5.1 and then updating the gem later)

If they are not already BIGINT, you can use the migration action found in the source below, pasted here for convenience:

change_column :your_table_name, :id, :bigint

Source: http://www.mccartie.com/2016/12/05/rails-5.1.html

Answer 2

Have you tries this code in migration file?

  def change
    create_table :table_name, id: false do |t|
      t.bigint :id, null: false
      t.index :id, name: "pk_table_name", unique: true
    end
  end

And in model:

class ModelName < ApplicationRecord
  self.primary_key = :id
end