latompa

-- I had an existing products table, and needed to denormalize two fields for faster sorting.
-- The number of rates and total rating is currently in a ratings table, and needs to be copied to products

create table products (
 id integer, 
 name varchar(16), 
 ratings_count integer,
 total_rating integer
);

latompa

-- building on data from my scenario http://gist.github.com/44489
-- and bayesian rating http://www.thebroth.com/blog/118/bayesian-rating

assume we have a products table and we want to sort products based on their rating.
With bayesian rating, you get better weighting, so that a single 5 star vote won't show up as "top product"

select * from products;
mysql> select * from products;
+------+--------+---------------+--------------+---------+
| id   | name   | ratings_count | total_rating | weight  |

latompa

You are using attachment_fu and have a database like so

id      product_id  parent_id  content_type    thumbnail  filename
1       500         (null)     image/png       (null)     ipod.png
2       (null)      1          image/png       medium     ipod_medium.png
3       (null)      1          image/png       large      ipod_large.png

and you want to produce a list of all your s3 urls (for copying a bucket maybe)

product_images/1/ipod.jpg

latompa

-- You have a products table, and want to show the ones a user can afford first sorted on price
-- followed by the products he can't afford, also sorted

create table products(id integer, name varchar(32), price integer)

insert into products values
(1,"teddy bear",10),
(2,"red fire engine",5),
(3,"doll house",50),
(4,"lego castle",190),

latompa

class Account < ActiveRecord::Base
  has_many :balance_transfers
  has_many :orders

  def purchase_order(description, cost)
    begin
      transaction do
        balance_transfers.create! :change=>cost
        orders.create! :description=>description
      end

latompa

require 'rubygems'
require 'activesupport'

module Fleykr
 mattr_accessor :token
 
 def self.search_photos
   p "searching, and my token is #{Fleykr.token}"
 end
end

latompa

require 'rubygems'
require 'lib/fleakr'

Fleakr.api_key       = 'API_KEY'
Fleakr.shared_secret = 'SECRET'
MAX_TRIES = 100

user_list = [{:auth_token => "TOKEN_1", :owner_id  => "USER_1"}, 
             {:auth_token => "TOKEN_2", :owner_id  => "USER_2"}]

latompa

#
# In the following test, the setup is supposed to create a variable, 
#  but fails because of a missing method
#
# If you run this test, you wont see the setup error, 
#  it's being masked by teardown, because @some_object is nil
#

require 'test/unit'
require 'rubygems'

latompa

You have an audit table
       created       | action 
---------------------+--------
 2009-01-01 00:00:00 | create
 2009-01-02 00:00:00 | delete
 2009-01-15 00:00:00 | create
 2009-01-16 00:00:00 | create

and you want a report with two counts, created and deleted for each week

latompa

-- table
create table members (id integer, age integer);

-- data
insert into members (id,age) values
(1,10), (2,20), (3,30), (4,25), (5,28), (6,37), (7,38), (8,68), (9,9);

-- query
select
SUM(case when age between 1 and 20   then 1 else 0 end) as "1-20",