Flowdock
method

up_only

Importance_1
v6.0.0 - Show latest stable - 0 notes - Class: ActiveRecord::Migration
up_only() public

Used to specify an operation that is only run when migrating up (for example, populating a new column with its initial values).

In the following example, the new column published will be given the value true for all existing records.

class AddPublishedToPosts < ActiveRecord::Migration[5.2]
  def change
    add_column :posts, :published, :boolean, default: false
    up_only do
      execute "update posts set published = 'true'"
    end
  end
end
Show source
Register or log in to add new notes.