Using AuthLogic

Hello, I'm trying to use the authlogic to make my login in my app.

The problem is when I change my user model.

user model:

class User < ActiveRecord::Base
  attr_accessible :crypted_password, :email, :password_salt,
:persistence_token, :username
  acts_as_authentic
end

create_users migration

class CreateUsers < ActiveRecord::Migration
  def change
    create_table :users do |t|
      t.string :username
      t.string :email
      t.string :crypted_password
      t.string :password_salt
      t.string :persistence_token

      t.timestamps
    end
  end
end

user controller

class UserController < ApplicationController
  def index
  end
end

database.yml

development:
  adapter: mysql2
  encoding: utf8
  database: login_development
  user: root
  password:
  pool: 5
  timeout: 5000

The error is that:

StandardError in UserController#index

You must establish a database connection before using acts_as_authentic

app/models/user.rb:3:in `<class:User>'
app/models/user.rb:1:in `<top (required)>'
app/controllers/user_controller.rb:1:in `<top (required)>'

When I refresh the page, this error appears:

NoMethodError in UserController#index

undefined method `key?' for nil:NilClass

How can I solve this ?

Thank you.