getting rudimentary query saving and loading to work

app/models/cost_query.rb

@@ -129,12 +129,23 @@ class CostQuery < ActiveRecord::Base
       hash[filter.class.underscore_name.to_sym] = filter.values
       hash
     end
+    params[:fields] = sel_filters.collect { |f| f.class.underscore_name }
     rows = group_bys.select &:row?
     columns = group_bys - rows
     params[:groups] = { :rows => rows.map { |gb| gb.class.field }, :columns => columns.map { |gb| gb.class.field } }
     params
   end
 
+  def hash
+    filter_string = filters.inject("") do |str, f|
+      str + f.class.underscore_name + f.operator.to_s + (f.values ? f.values.to_json : "")
+    end
+    filter_string = group_bys.collect(&:class).sort_by(&:underscore_name).inject(filter_string) do |string, gb|
+      string.concat(gb.underscore_name)
+    end
+    Digest::MD5.hexdigest(filter_string)
+  end
+
   private
 
   def minimal_chain!

app/views/cost_reports/_saved_queries.rhtml

@@ -0,0 +1,15 @@
+<%#
+  This partial requires the following locals:
+    queries   A Collection of CostQuery Objects
+%>
+
+<% queries.each do |query| %>
+
+  <%= link_to_remote "<span><em>#{query.name}</em></span>",
+                    { :url => ({ :set_filter => 1, :action => 'index' }.merge CostQuery.load(query.yamlized).to_params),
+                      :condition => 'Ajax.activeRequestCount === 0',
+                      :update => "content",
+                      :eval_scripts => true
+                    }, :class => 'button send_query' %>
+
+<% end %>

app/views/cost_reports/index.rhtml

@@ -13,6 +13,7 @@
 
 <h2><%= l(:label_cost_report) %></h2>
 <% html_title( l(:label_cost_report) ) %>
+  <%= render :partial => 'saved_queries', :locals => { :queries => CostQuery.all }  %>
 
 <% form_for @query, :url => {:controller => 'cost_report', :action => 'new' }, :html => {:id => 'query_form', :method => :post} do |query_form| %>
 <div id="query_form_content">
@@ -42,6 +43,7 @@
                     { :url => { :save_query => 1 },
                       :before => 'selectAllOptions("group_by_rows");selectAllOptions("group_by_columns");',
                       :with => "Form.serialize('query_form')",
+                      :update => 'content',
                       :eval_scripts => true
                     }, :class => 'icon icon-save' %>
   <% end %>