Background
Active record's find returns an array, you can use group_by to put the result into a groups. However group_by returns a hash, a hash does not have any order, When you iterate thru the hash it comes out in any order.
Better Approach
Write a function to return a array of records grouped by some critiera (Like in_groups_of). Now you can simply iterate thru using each and each. In my implementation I have assumed the data is already ordered
The Code
class Array
def in_groups_by
# Group elements into individual array's by the result of a block
# Similar to the in_groups_of function.
# NOTE: assumes array is already ordered/sorted by group !!
curr=nil.class
result=[]
each do |element|
group=yield(element) # Get grouping value
result << [] if curr != group # if not same, start a new array
curr = group
result[-1] << element
end
result
end
end
Go on Give it a go, Copy and paste the below code into say the bottom of "environment.rb", re-cycle the server, and try
An Example
def customers_grouped_by_country
ds=Customer.find(:all, :order => :order=>"county_id")
ds.in_groups_by(&:county_id)
# or the alternative syntax
# ds.in_groups_by { |r| r.country_id }
end
<% customers_grouped_by_country.each do |group| %>
<h1>Country <%= group[0].country_id></h1>
<% group.each do |e| %>
<p><%= e.name %></p>
<% end %>
<% end >
