menu, table,rooms, orders structure

app/models/order_item.rb

@@ -0,0 +1,10 @@
+class OrderItem < ApplicationRecord
+  #Associations
+  belongs_to :order
+
+  #Validation
+  validates_presence_of :item_code, :item_name, :qty
+  validates :qty, numericality: { :greater_than 0 }
+  validates_associated :orders
+
+end