テーブルを作ってインデックスを追加

DB = Sequel.sqlite('tusers.db')
unless DB.table_exists? :users
  DB.create_table :users do
      primary_key :id
      text :screen_name, :unique => true
      text :name
      text :description
      integer :utc_offset
      text :time_zone
      text :location
      integer :followers_count
      integer :friends_count
      integer :statuses_count
  end
  DB.add_index :users, :screen_name
end