gistfile1.rb

# rails g model Book name:string:index isbn:string:uniq description:text user:references content:string{30}
class CreateBooks < ActiveRecord::Migration
  def change
    create_table :books do |t|
      t.string :name
      t.string :isbn
      t.text :description
      t.references :user, index: true
      t.string :content, limit: 30

      t.timestamps
    end
    add_index :books, :name
    add_index :books, :isbn, unique: true
  end
end