AR Challenges

gistfile1.txt

2-1 Order.first.items << Item.first

2-2 

2-3
before_destroy :destroy_orders
def destroy_orders
  self.orders.delete_all
end

2-4
Order.order(:created_at)[10..19]

2-5
Order.all.collect {|order| order.items.map {|item| item if item.id == 1}}.map {|order| order.compact}.flatten

1-1 
items = Item.arel_table
Item.where(items[:name].matches("%rubber%"))

1-2
Order.all.inject([]) {|result, order| result << [order, order.items.count]}.sort_by {|entry| entry[1]}.reverse[0..4]

1-3
Order.order(:created_at)[0..9]

1-4
def self.last_month # Show only products of last month.
  where(:purchase_date => 1.month.ago.beginning_of_month..1.month.ago.end_of_month)
end