Rails: AcriveRecord::basis

ORM

Create

  order = Order.new(:name => "Kyo Endo", :age => 45)

  order.save

    or

  order = Order.create(...)

  orders = Order.create([

    {:name => "Kyo Endo", :age => 45},

    {:name => "Keyes Jarrett", :age => 20}

    ])

Read

  orders = Order.find(:all, :conditions => params[:order])

  orders = Order.find(:all, :conditions => ["name = :name and pey_type = :pay_type", params[:order])

  orders = Order.find(:all, :conditions => ["name like ?", params[:name]+"%"])

  orders = Order.find(:all, :conditions => "name='Dave'",

                      :order => "pay_type, shipped_at DESC",

                      :limit => 10)

  order = Order.find(:first, :conditions => "name = 'Kyo'",

                     :order => "id DESC")

  order = Order.find_by_sql("select line_items.* from line_items, orders " + "where order_id = orders.id" + "and orders.name = 'Kyo Endo'")

  

  average = Order.average(:amount)

  total = Order.sum(:amount)

  number = Order.count

  minimum = Order.minimum :amout, :conditions => "amout > 20"

  

  order = Order.find_by_name("keyes")

  order = Order.find_all_by_email(params['email'])

  user = User.find_by_name_and_password(name, pw)

Update

  order = Order.find(123)

  order.name = "Fred"

  order.save

  

  order.update_attribute(:name, "Barney")

  order.update_attributes(:name => "Barney", :email => "barney@bedrock.com")

Delete

  Order.delete(123)

  Order.delete([12,13,15])

  Product.delete_all(["preice > ?", @expensive_price])

  

  order.destroy

  Order.destroy_all(["shipped_at < ?", 30.days.ago])

Aggregation

  composed_of :name to Customer Class

  customer = Customer.find(123)

  puts customer.name.first