006_create_line_items.rb

用NETBEANS编的

# Copyright (c) 2006 The Pragmatic Programmers, LLC.
# Reproduced from the book "Agile Web Development with Rails, 2nd Ed.",
# published by The Pragmatic Bookshelf.
# Available from www.pragmaticprogrammer.com/titles/rails2
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class CreateLineItems < ActiveRecord::Migration
  def self.up
    create_table :line_items do |t|
      t.column :product_id,  :integer, :null => false
      t.column :order_id,    :integer, :null => false
      t.column :quantity,    :integer, :null => false
      t.column :total_price, :decimal, :null => false, :precision => 8, :scale => 2
    end

    execute "alter table line_items 
               add constraint fk_line_item_products 
               foreign key  (product_id) references products(id)"

    execute "alter table line_items 
               add constraint fk_line_item_orders
               foreign key  (order_id) references orders(id)"
  end

  def self.down
    drop_table :line_items
  end
end