The following migration can be used to add devise required columns to an existing users table.
class AddDeviseColumnsToUser < ActiveRecord::Migration def change change_table :users do |t| # if you already have a email column, you have to comment the below line and add the :encrypted_password column manually (see devise/schema.rb). t.database_authenticatable t.confirmable t.recoverable t.rememberable t.trackable t.token_authenticatable t.timestamps end end end
Note: If your existing users table already has a column
t.database_authenticatable will fail, because it tries to add
t.database_authenticatable will add two columns,
encrypted_password, in line of
t.string :encrypted_password, :null => false, :default => '', :limit => 128
You can see the list of columns generated automatically by Devise here:
Note: it is sometimes easier to just delete the table and re-create it using Devise instead of trying to retrofit Devise into your table.
You will still have errors in your migration with the 2.0 schema, if you have existing fields such as email.
To eliminate migration errors on duplicate fields, use
t.change as shown below.
t.change :email, :string, :null => false, :default => ""
Notice that for
t.change to work, you have to specify the type for the field being changed. In the case of the email migration above, the email field was of type string.