Couldn't find without an ID

hello ,
i have problem when i want to show page after user submit data into
database.
this is code in controller

class ComponentsController < ApplicationController

  def index
  end

  def databases
    @title = "Database"
    if request.post?and params[:seq]
      params[:seq][:sequence].gsub!(/\s/,"")
      params[:seq][:sequence].upcase!
      @seq = Seq.new(params[:seq])
      if @seq.save
        flash[:notice] = "sequence submitted !"
        redirect_to :action => "show"
      end
    end
  end

  def show
    @title = "Show"
    @seq = Seq.find(params[:id])
    end
  end
end

when i run i have error like is

ActiveRecord::RecordNotFound in ComponentsController#show
Couldn't find Seq without an ID
/usr/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/
base.rb:1572:in `find_from_ids'
/usr/lib/ruby/gems/1.8/gems/activerecord-2.3.2/lib/active_record/
base.rb:616:in `find'
/home/apple/www/rcc_eri/app/controllers/components_controller.rb:29:in
`show'

thank you very much Reinhart
it’ work. -___-