cryptobot/db/migrate/20171129210307_create_markets.rb

class CreateMarkets < ActiveRecord::Migration[5.1]
  def change
    create_table :markets do |t|
      t.string :name
      t.string :url
      t.boolean :is_active, default: true

      t.timestamps
    end
    add_index :markets, :is_active
  end
end