Displaying records with static look up table source...

Greetings All,

I hope you all understand what I am writing here. Lots of views involve displaying date from static ‘look up’ tables: states, countries, type…

From all of the documentation I have read, the standard code conduct seems @look_up_object = LookUpModel.find .where. conditions => ids match

I pursued that structure, and for long listings, so many calls to database really bothered me.

So I re-wrote the code on look-up for my case static item_conditions, containing only two field: conditions and item_conditions_id:

In the view I now have, following found parent records:

    <% @icond = Itemconditions.find(:all, :readonly) %>
    <% @ih = Hash.new %>
    <% @ih2 = Hash.new %>
    <% @ih = @icond.to_a.map(&:serializable_hash) %>
    <% for kv in @ih %>
      <% @ih2[kv.fetch("item_conditions_id")]  = kv.fetch("conditions") %>
     <% end %>

And then later for iterative record output I have in the view, ldr as the parent data source

<label class="item_listing">Condition:&nbsp;<%= @ih2[ldr.item_condition_id.to_s] %></label>

Benchmarked this and vastly faster. Deployed it, no problems/errors. I have researched Ruby and Ruby on Rails API. I have not found a simpler, more native approach. Masters if you are aware of Ruby on Rails way, please let me know.


Liz McGurty

displaying data

I would recommend you to remove this code in your view to a presenter and use AR include method to add a your relationships in the same query to fetch from the database. It will avoid de n+1 issue.

Thank you, Thiagocifani! I was not aware of the include method. And, by the way, I visited your about.me page and it is very impressive. Liz