jrallison

jQuery("#pages ul li").hover(function(){
  jQuery(this).stop(true).animate({
    marginTop: "10px"
  }, 250);
}, function(){
  jQuery(this).stop(true).animate({
    marginTop: "0px"
  }, 250);
});

jrallison

def first_n_primes(n)
   return [] if n <= 0

   @primes ||= [2]
   x = @primes.last + 1
  
   until @primes.length >= n
      prime = true
      
      @primes.each do |p|

jrallison

Nameserver trace for challenge.gov:

Looking for who is responsible for root zone and followed d.root-servers.net.
Looking for who is responsible for gov and followed f.usadotgov.net.
Looking for who is responsible for challenge.gov and followed a.ns.zerigo.net.
Nameservers for challenge.gov:

c.ns.zerigo.net returned (SERVFAIL)
a.ns.zerigo.net returned (SERVFAIL)

jrallison

var image = new Image();
image.src = url;
image.onload = function() {
  // Display image
};

jrallison

<% @somethings.each do |something| %>
  <%= cache("somethings:#{something.id}", :time => something.created_at) do %>
    <div class="something">
      <%= render "somethings/expensive_calculation" %>

      <!-- time.strftime(...) calculated dynamically every time -->
      <p class="timestamp"><%= time.strftime("%B %d, %Y") %></p>
    </div>
  <% end %>
<% end %>

jrallison

# Model

class Model < ActiveRecord::Base
  default_scope where(:hidden => false)

  def hide!
    update_attributes!(:hidden => true)
  end
end

jrallison

1) Rollout configuration is in models

/web/models/lib/models/config/rollout.rb

$rollout = Rollout.new(REDIS)

$rollout.define_group(:admin) do |user|
  user.admin?
end

jrallison

# In controllers
mixpanel("event name")

# Anywhere else
Mixpanel.new(:event => "event name", :id => some_user.id, :ip => ???).track!

# ApplicationController
def mixpanel(event, opts = {})
  unless current_user.admin? || masquerading?
    opts = {:event => event, :id => current_user.id, :ip => request.remote_ip}.merge(opts)

jrallison

EXPLAIN

mysql> explain SELECT * FROM `submissions` WHERE `submissions`.`id` = 5334;
+----+-------------+-------------+-------+---------------+---------+---------+-------+------+-------+
| id | select_type | table       | type  | possible_keys | key     | key_len | ref   | rows | Extra |
+----+-------------+-------------+-------+---------------+---------+---------+-------+------+-------+
|  1 | SIMPLE      | submissions | const | PRIMARY       | PRIMARY | 4       | const |    1 |       | 
+----+-------------+-------------+-------+---------------+---------+---------+-------+------+-------+

1 row in set (0.01 sec)

jrallison

diff --git a/Gemfile b/Gemfile
index 861f72a..e63813d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -5,7 +5,8 @@ gem 'rails', '3.0.10'
 # Bundle edge Rails instead:
 # gem 'rails', :git => 'git://github.com/rails/rails.git'
 
-gem 'sqlite3'
+gem 'mysql'