gamov

    requested_items.inject(0) { |sum,it| sum += it.value }   #works
#    requested_items.inject() { |sum,it| sum += it.value }   #not working
#    requested_items.sum {|it| it.price }  # not working

gamov

# our multi_group http://rails.lighthouseapp.com/projects/8994/tickets/120-patch-activerecord-calculations-only-accept-one-grouping-field#
# isn't updated for 2.2 yet. In the meantime, this poor man's version gives you the same results with some delimitter tom foolery.
# 
# note: be careful to ensure that your group_by do not use the delimitter 
# usage:
#   self.multi_count(:id, :distinct => true, :group => [:symptom_id, :treatment_id])        
#   [[["138", "1018"], 187], [["138", "427"], 373], [["6", "1018"], 197], [["6", "427"], 393]]
class ActiveRecord::Base  
  def self.multi_count(field, opts = {})
    fq_field_name = "#{table_name}.#{field}"

gamov

## greatest n per group

SELECT * FROM shipping_items As t1 
WHERE t1.created_at = (SELECT Max(created_at) 
     FROM shipping_items As t2
     WHERE t2.item_variant_id = t1.item_variant_id 
          AND t2.item_variant_id in (11,10)) 

gamov

  def save_batches_alloc(hash)
    if self.attribute_names.include?('batches_alloc')
      write_attribute(:batches_alloc, hash)
    else
      @batches_alloc= hash
    end
  end
  def load_batches_alloc
    if self.attribute_names.include?('batches_alloc')
      read_attribute(:batches_alloc)

gamov

  def verify_no_associated_charges
    unless charges.empty?
      errors.add_to_base("You cannot delete the charge code #{code} because it has associated charges")
      false
    else
      true
    end
  end

gamov

class SessionsController < ApplicationController
   skip_before_filter :login_required, :only => [:new, :create]

   layout nil

  def new
    render #:layout => nil
  end

  def create

gamov

  def any_missing_specs
    if item_variants.loaded?
      item_variants.any?{|si| si.m3 == 0 || si.weight == 0}
    else
      item_variants.where({:m3 => 0 } | {:weight => 0}).size != 0 #metawhere
    end
  end

gamov

class Shipment
  has_many :shipping_items, :inverse_of => :shipment, :dependent => :destroy do
    def linked_po_ids
      joins(:purchased_item => :purchase_order).select('DISTINCT purchase_orders.id AS po_id').map{|si| si.po_id}
    def linked_pos
      ? #how to return the purchase orders (objects) ?
    end
  end

def linked_pos

gamov

def update_deliver_partially
    @purchase_order = PurchaseOrder.find(params[:id], :include => {:purchased_items => {:item_variant => :item_family}})
#    authorize! :update
    @purchase_order.attributes = params[:purchase_order]

    @stock_receipt = @purchase_order.stock_receipts.to_a.find{|sr| sr.new_record?}

    #logger.debug @stock_receipt.inspect

#    @purchased_items.each {|pi| p "in controller #{pi.wh_alloc_hash.inspect}"}

gamov

class MyModel < ActiveRecord::Base

  serialize :preferences, Hash

  PREFS_KEYS = [:hostname, :has_retail]

  PREFS_KEYS.each do |key|
    define_method(key) do
      preferences[key]
    end