```ruby
class CreateVotes < ActiveRecord::Migration
  def change
    create_table :votes do |t|
      t.integer :user_id, index: true, foreign_key: true
      t.boolean :value
      t.string :voteable_type
      t.integer :voteable_id, index: true, foreign_key: true

      t.timestamps
    end
  end
end
```

Edit migration -- remove redundant index statement on polymorphic association column
user
```ruby
class CreateVotes < ActiveRecord::Migration
  def change
    create_table :votes do |t|
      t.integer :user_id, index: true, foreign_key: true
      t.boolean :value
      t.string :voteable_type
      t.integer :voteable_id

      t.timestamps
    end
  end
end
```
assistant