Rails output number of records with X in field?

Question

Hi Everyone,

I have a number of records in a model called Kases, each kase record has a status which can be Active, On Hold, Invoice Sent or Archived.

I am trying to work out how to add a number on the dashboard for the total number of kase records, the total number of kase records marked as on hold, the total number of kase records marked as invoice sent, and the total number of kase records marked as archived.

Currently, I set the status of the kase record with the following:

<li>Case Status<span><%= f.select "kase_status", ['Active', 'On Hold', 'Archived', 'Invoice Sent'] %></span></li>

The kase_status is a field in the kases table, and is a string:

  t.string :kase_status

Is there a simple way to do this?

Thanks,

Danny

EDIT:

Console Error Message:

>> Kases.find(:all).select { |k| k.kase_status == "Active"}.size
NameError: uninitialized constant Kases
    from /Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:443:in `load_missing_constant'
    from /Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:80:in `const_missing'
    from /Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/dependencies.rb:92:in `const_missing'
    from (irb):1
>> 

Answer 1

Yep!

Update

Following the advice of everyone, I updated the answer. This is a far faster and more appropriate way to accomplish this.

Controller

@kases_active_count = Kase.count(:conditions => ['kase_status = ?', 'Active'])
@kases_on_hold_count = Kase.count(:conditions => ['kase_status = ?', 'On Hold'])
@kases_archived_count = Kase.count(:conditions => ['kase_status = ?', 'Archived'])
@kases_invoice_sent_count = Kase.count(:conditions => ['kase_status = ?', 'Invoice Sent'])

HTML

<%= @kases_active_count %>

Answer 2

You can use the count method on Kase, for example:

Kase.count(:conditions => ['kase_status = ?', 'Active'])

This means you just do a query to count the number of matching objects rather than fetching every single Kase instance from the database and checking the value.

If you want to get all of the different status values in a single query you can do:

@all_counts = Kase.find(:all, :group => 'kase_status', :select => 'kase_status, count(*) as how_many)

which will return you a collection of Kase-like objects with the kase_status and how_many attributes. You can then use that collection to display all of your status counts. E.g.

<% @all_counts.each do |c| %>
    <%= c.kase_status %> : <%= c.how_many %>
<% end %>