Question

I have one instance variable with two records.

           id   item_with_detail_id  quantity

           100       205                3


           101       205                5

Now, i want the result as follows using Active record group_by .

           100       205                8

i tried with

@bill_details=@bill_details.group_by{|bd| bd.item_with_detail_id}.values.map(&:first)

but its not working. Please help me to achieve the result.

Answer 1

Finally i solved this problem. As follows

In the controller =>

@bill_details = @bill_details.group_by{|bd| bd.item_with_detail_id}.values

it will give the following result

 #[[#<BillDetail id: 100, item_with_detail_id: 205, quantity: 3, #<BillDetail id:101, item_with_detail_id: 205, quantity: 5]]

And in the view page:

<% for bd in @bill_details%>
  <%quantity=0%>
  <%for bill_detail in  bd%>
  <%quantity+=bill_detail.quantity%>
  <%end%>
  <%bd=bd.first%>
<%end%>