How to use long id in Rails applications?

Question

How can I change the (default) type for ActiveRecord\'s IDs? int is not long enough, I would prefer long. I was surprised that there is no :long for the migrations - does on

Answer 1

In rails4, you can do it.

Following is an example to create a Dummy model in rails4 & postgres,

xxx_migrate_dummies.rb:

class CreateDummies < ActiveRecord::Migration
  def change
    create_table :dummies, :id => false do |t|
      t.column :id, :serial8, primary_key: true
      t.string :name, :limit => 50, null: false
      t.integer :size, null: false

      t.column :create_date, :timestamptz, null: false
    end
  end
end

What it did:

• It use serial8 as id type, which is 64 bit integer, and define it as primary key.
• It use timestamptz as datetime type, which contain the timezone info, this is important for a application that go across multiple timezones.