Chapter 10 migrations that ciopy data

have two migrations
one:
class AddPriceToLineItems < ActiveRecord::Migration def change add_column :line_items, :price, :decimal, default: 0, precision: 8, scale: 2 end
end

two:
class CopyProductIdToLineItem < ActiveRecord::Migration def up Cart.all.each do |cart| cart.line_items.each do |item| item.price = item.product.price say item.product.title say item.quantity say item.price end end end def down end
end

After migrating price of the line_items in cart equals 0 ( default value )
But while migration say gives item.price = correct values
Looks like it becomes 0 later