She is a smart person, but again, she isn’t a programmer. I thought Codecademy would be a great way to introduce her to programming for the web. As a programmer, I thought it was extremely well made and assumed it would work for anyone.

She landed on the homepage and read the instructions.

She wrote her name (“Elizabeth”), then decided however to change it to the shortened form of her name, “Liz”. To do so she highlighted the whole string she had just typed and tried to press the backspace key to delete it. The whole page disappeared and the browser redirected her to the new tab.

Liz: “Why did it do that?”

Me: “You can’t highlight a word like you’d do in Microsoft Word. You’re in a browser, so the backspace button tells the browser to go back to the previous page you visited in that particular tab. You need to delete the string one letter at the time.”

She reopened the page and tried again, this time things were successful.

Next, she had to measure the length of her name. But she forgot the quotes, so she got this:

Liz: “What happened?”

Me: “What do you think happened?”

Liz: “Some kind of error, but what does ‘Liz is not defined’ mean?”

Me: “You accidentally forgot the quotes.”

Liz: “Oh, OK, let me try again.”

She wrote the first quote but pressed enter before immediately realizing she had forgotten the closing one. As such she encountered the following scenario:

Liz: “I messed it, let me try again.”

Liz: “I typed it right this time, why didn’t it work?”

Me: “Since you didn’t close the first string, it thinks that the second line is still part of the first command. Do you know how to get out of this?”

Liz: “No, but let me try.”

No, she didn’t close the string and pressed enter twice or deleted a bunch of characters (this web REPL allows it, kudos to Codecademy). She simply reloaded the page. Thankfully the same exercise (#1) was reloaded. After completing it successfully though, instead of exercise #2, exercise #0 reappeared, asking her to enter her first name again.

After raising an eyebrow at that point, she went along with it. Next she was asked to try some math.

She can’t be faulted for thinking that “for instance” meant she could try something else. Yet, she got an “Oops, try again.” message.

At that point I suspended this tiny hallway test and I asked her what she thought of this system. She found the site to be a bit unintuitive, but above all felt like she didn’t know how to get unstuck when she made an error.

Now, before you all jump in and tell me that my friend is dumb, that she’ll never be a programmer, or that you can’t idiot-proof a design, keep in mind the very point of this post.

Usability is hard because real users use our UIs and software in different and unexpected ways. Codecamedy did a very good job, but even they left plenty of room for improvement. As web developers it’s our duty to give usability and user experience a significant amount of attention. The UI is the software to the end user.

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As some of you know, I run a service called Any New Books?, which emails you a list of new books that are related to the categories of your choice each week. For the most part I pulled this list from the weekly staff picks there throughout this past year, just in time for your Christmas shopping.

The books are ordered by their current sale rank on Amazon (from the most popular to the least popular at the moment, with hardcovers first). I hope this page will help you discover a few titles you may have not have noticed yet.

[Mathematics book list]

	The Information: A History, a Theory, a Flood Stores: USA | Canada | Italy | Kindle | UK Kindle By James Gleick ISBN: 0375423729 Publisher: Pantheon Publication date: March 1, 2011 Binding: Hardcover Estimated price: $16.82 Share this book on Twitter |Facebook
	The Art of Computer Programming, Volumes 1-4A Boxed Set Stores: USA | Canada By Donald E. Knuth ISBN: 0321751043 Publisher: Addison-Wesley Professional Publication date: March 13, 2011 Binding: Hardcover Estimated price: $190.47 Share this book on Twitter |Facebook
	Algorithms (4th Edition) Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Robert Sedgewick, Kevin Wayne ISBN: 032157351X Publisher: Addison-Wesley Professional Publication date: March 19, 2011 Binding: Hardcover Estimated price: $59.99 Share this book on Twitter |Facebook
	The Art of Computer Programming, Volume 4A: Combinatorial Algorithms, Part 1 Stores: USA | UK | Canada | Italy By Donald E. Knuth ISBN: 0201038048 Publisher: Addison-Wesley Professional Publication date: January 22, 2011 Binding: Hardcover Estimated price: $53.15 Share this book on Twitter |Facebook
	GPU Computing Gems Emerald Edition Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Editors at Morgan Kaufmann ISBN: 0123849888 Publisher: Morgan Kaufmann Publication date: February 7, 2011 Binding: Hardcover Estimated price: $29.06 Share this book on Twitter |Facebook
	Visualize This: The FlowingData Guide to Design, Visualization, and Statistics Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Nathan Yau ISBN: 0470944889 Publisher: Wiley Publication date: July 20, 2011 Binding: Paperback Estimated price: $20.48 Share this book on Twitter |Facebook
	Programming Android Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Zigurd Mednieks, Laird Dornin, G. Blake Meike, Masumi Nakamura ISBN: 1449389694 Publisher: O’Reilly Media Publication date: August 5, 2011 Binding: Paperback Estimated price: $22.98 Share this book on Twitter |Facebook
	JavaScript: The Definitive Guide: Activate Your Web Pages Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By David Flanagan ISBN: 0596805527 Publisher: O’Reilly Media Publication date: May 10, 2011 Binding: Paperback Estimated price: $27.48 Share this book on Twitter |Facebook
	iOS Programming: The Big Nerd Ranch Guide (2nd Edition) Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Joe Conway, Aaron Hillegass ISBN: 0321773772 Publisher: Addison-Wesley Professional Publication date: July 2, 2011 Binding: Paperback Estimated price: $26.95 Share this book on Twitter |Facebook
	Programming in Objective-C, Third Edition Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Stephen G. Kochan ISBN: 0321711394 Publisher: Addison-Wesley Professional Publication date: June 20, 2011 Binding: Paperback Estimated price: $25.99 Share this book on Twitter |Facebook
	Cocoa Programming for Mac OS X (4th Edition) Stores: USA | Canada | Kindle | UK Kindle By Aaron Hillegass, Adam Preble ISBN: 0321774086 Publisher: Addison-Wesley Professional Publication date: November 19, 2011 Binding: Paperback Estimated price: $27.99 Share this book on Twitter |Facebook
	Introducing HTML5 (2nd Edition) Stores: USA | UK | Canada | Kindle | UK Kindle By Bruce Lawson, Remy Sharp ISBN: 0321784421 Publisher: New Riders Press Publication date: October 28, 2011 Binding: Paperback Estimated price: $14.49 Share this book on Twitter |Facebook
	Programming Python Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Mark Lutz ISBN: 0596158106 Publisher: O’Reilly Media Publication date: January 7, 2011 Binding: Paperback Estimated price: $36.42 Share this book on Twitter |Facebook
	Beginning Android Application Development Stores: USA | UK | Canada | Italy By Wei-Meng Lee ISBN: 1118017110 Publisher: Wrox Publication date: April 19, 2011 Binding: Paperback Estimated price: $15.99 Share this book on Twitter |Facebook
	Agile Web Development with Rails Stores: USA | UK | Canada | Italy By Sam Ruby, Dave Thomas, David Heinemeier Hansson ISBN: 1934356549 Publisher: Pragmatic Bookshelf Publication date: March 31, 2011 Binding: Paperback Estimated price: $22.36 Share this book on Twitter |Facebook
	Eloquent Ruby Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Russ Olsen ISBN: 0321584104 Publisher: Addison-Wesley Professional Publication date: February 21, 2011 Binding: Paperback Estimated price: $24.99 Share this book on Twitter |Facebook
	Matlab, Second Edition: A Practical Introduction to Programming and Problem Solving Stores: USA | UK | Canada | Kindle | UK Kindle By Stormy Attaway ISBN: 0123850819 Publisher: Butterworth-Heinemann Publication date: August 11, 2011 Binding: Paperback Estimated price: $35.44 Share this book on Twitter |Facebook
	Java Performance Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Charlie Hunt, Binu John ISBN: 0137142528 Publisher: Prentice Hall Publication date: October 10, 2011 Binding: Paperback Estimated price: $40.73 Share this book on Twitter |Facebook
	Gamification by Design: Implementing Game Mechanics in Web and Mobile Apps Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Gabe Zichermann, Christopher Cunningham ISBN: 1449397670 Publisher: O’Reilly Media Publication date: August 19, 2011 Binding: Paperback Estimated price: $14.34 Share this book on Twitter |Facebook
	Learn You a Haskell for Great Good!: A Beginner’s Guide Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Miran Lipovaca ISBN: 1593272839 Publisher: No Starch Press Publication date: April 18, 2011 Binding: Paperback Estimated price: $21.55 Share this book on Twitter |Facebook
	Supercharged JavaScript Graphics: with HTML5 canvas, jQuery, and More Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Raffaele Cecco ISBN: 1449393632 Publisher: O’Reilly Media Publication date: August 2, 2011 Binding: Paperback Estimated price: $21.31 Share this book on Twitter |Facebook
	Arduino Robotics Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By John-David Warren, Josh Adams, Harald Molle ISBN: 1430231831 Publisher: Apress Publication date: July 14, 2011 Binding: Paperback Estimated price: $26.38 Share this book on Twitter |Facebook
	HBase: The Definitive Guide Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Lars George ISBN: 1449396100 Publisher: O’Reilly Media Publication date: September 20, 2011 Binding: Paperback Estimated price: $24.99 Share this book on Twitter |Facebook
	The Tangled Web: A Guide to Securing Modern Web Applications Stores: USA | Canada | Kindle | UK Kindle By Michal Zalewski ISBN: 1593273886 Publisher: No Starch Press Publication date: November 26, 2011 Binding: Paperback Estimated price: $26.50 Share this book on Twitter |Facebook
	MongoDB in Action Stores: USA By Kyle Banker ISBN: 1935182870 Publisher: Manning Publications Publication date: December 16, 2011 Binding: Paperback Estimated price: $27.46 Share this book on Twitter |Facebook
	Programming Pig Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Alan Gates ISBN: 1449302645 Publisher: O’Reilly Media Publication date: October 20, 2011 Binding: Paperback Estimated price: $24.99 Share this book on Twitter |Facebook
	The Python Standard Library by Example Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Doug Hellmann ISBN: 0321767349 Publisher: Addison-Wesley Professional Publication date: June 11, 2011 Binding: Paperback Estimated price: $31.49 Share this book on Twitter |Facebook
	The Joy of Clojure: Thinking the Clojure Way Stores: USA | UK | Canada | Italy By Michael Fogus, Chris Houser ISBN: 1935182641 Publisher: Manning Publications Publication date: April 4, 2011 Binding: Paperback Estimated price: $21.99 Share this book on Twitter |Facebook
	Xcode 4 Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Richard Wentk ISBN: 111800759X Publisher: Wiley Publication date: June 28, 2011 Binding: Paperback Estimated price: $19.99 Share this book on Twitter |Facebook
	Programming Amazon EC2 Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Jurg van Vliet, Flavia Paganelli ISBN: 1449393683 Publisher: O’Reilly Media Publication date: March 14, 2011 Binding: Paperback Estimated price: $24.22 Share this book on Twitter |Facebook
	Advanced Mac OS X Programming: The Big Nerd Ranch Guide Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Mark Dalrymple ISBN: 0321706250 Publisher: Addison-Wesley Professional Publication date: August 28, 2011 Binding: Paperback Estimated price: $32.95 Share this book on Twitter |Facebook
	CUDA Application Design and Development Stores: USA | UK | Canada | Kindle | UK Kindle By Rob Farber ISBN: 0123884268 Publisher: Morgan Kaufmann Publication date: November 14, 2011 Binding: Paperback Estimated price: $43.98 Share this book on Twitter |Facebook
	Sinatra: Up and Running Stores: USA | Canada | Kindle | UK Kindle By Alan Harris, Konstantin Haase ISBN: 1449304230 Publisher: O’Reilly Media Publication date: December 1, 2011 Binding: Paperback Estimated price: $15.29 Share this book on Twitter |Facebook
	Management 3.0: Leading Agile Developers, Developing Agile Leaders Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Jurgen Appelo ISBN: 0321712471 Publisher: Addison-Wesley Professional Publication date: January 7, 2011 Binding: Paperback Estimated price: $29.50 Share this book on Twitter |Facebook
	Professional NoSQL Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Shashank Tiwari ISBN: 047094224X Publisher: Wrox Publication date: September 13, 2011 Binding: Paperback Estimated price: $16.99 Share this book on Twitter |Facebook
	Scalability Rules: 50 Principles for Scaling Web Sites Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Martin L. Abbott, Michael T. Fisher ISBN: 0321753887 Publisher: Addison-Wesley Professional Publication date: May 15, 2011 Binding: Paperback Estimated price: $16.96 Share this book on Twitter |Facebook
	Programming Concurrency on the JVM: Mastering Synchronization, STM, and Actors Stores: USA | UK | Canada | Italy By Venkat Subramaniam ISBN: 193435676X Publisher: Pragmatic Bookshelf Publication date: September 2, 2011 Binding: Paperback Estimated price: $19.29 Share this book on Twitter |Facebook
	Learning HTML5 Game Programming: A Hands-on Guide to Building Online Games Using Canvas, SVG, and WebGL Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By James L. Williams ISBN: 0321767365 Publisher: Addison-Wesley Professional Publication date: October 5, 2011 Binding: Paperback Estimated price: $16.54 Share this book on Twitter |Facebook
	Semantic Web for the Working Ontologist, Second Edition: Effective Modeling in RDFS and OWL Stores: USA | UK | Canada | Italy By Dean Allemang, James Hendler ISBN: 0123859654 Publisher: Morgan Kaufmann Publication date: June 3, 2011 Binding: Paperback Estimated price: $38.43 Share this book on Twitter |Facebook
	Brave NUI World: Designing Natural User Interfaces for Touch and Gesture Stores: USA | UK | Canada | Italy By Daniel Wigdor, Dennis Wixon ISBN: 0123822319 Publisher: Morgan Kaufmann Publication date: April 27, 2011 Binding: Paperback Estimated price: $18.49 Share this book on Twitter |Facebook
	Haskell: The Craft of Functional Programming (3rd Edition) Stores: USA | UK | Canada | Italy By Simon Thompson ISBN: 0201882957 Publisher: Addison-Wesley Professional Publication date: October 2, 2011 Binding: Paperback Estimated price: $44.96 Share this book on Twitter |Facebook
	Think Stats Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Allen B. Downey ISBN: 1449307116 Publisher: O’Reilly Media Publication date: July 22, 2011 Binding: Paperback Estimated price: $21.98 Share this book on Twitter |Facebook
	Rails 3 in Action Stores: USA | UK | Canada | Italy By Ryan Bigg, Yehuda Katz ISBN: 1935182277 Publisher: Manning Publications Publication date: September 28, 2011 Binding: Paperback Estimated price: $27.48 Share this book on Twitter |Facebook
	Test Driven Development for Embedded C Stores: USA | UK | Canada | Italy By James W. Grenning ISBN: 193435662X Publisher: Pragmatic Bookshelf Publication date: May 2, 2011 Binding: Paperback Estimated price: $19.37 Share this book on Twitter |Facebook
	MacRuby: The Definitive Guide: Ruby and Cocoa on OS X Stores: USA | UK | Canada | Kindle | UK Kindle By Matt Aimonetti ISBN: 1449380379 Publisher: O’Reilly Media Publication date: November 4, 2011 Binding: Paperback Estimated price: $16.70 Share this book on Twitter |Facebook
	Modern Information Retrieval: The Concepts and Technology behind Search (2nd Edition) Stores: USA | UK | Canada | Italy By Ricardo Baeza-Yates, Berthier Ribeiro-Neto ISBN: 0321416910 Publisher: Addison-Wesley Professional Publication date: February 10, 2011 Binding: Paperback Estimated price: $56.24 Share this book on Twitter |Facebook
	Designing Search: UX Strategies for eCommerce Success Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Greg Nudelman ISBN: 0470942231 Publisher: Wiley Publication date: May 24, 2011 Binding: Paperback Estimated price: $14.99 Share this book on Twitter |Facebook
	Windows Phone 7 Recipes: A Problem-Solution Approach Stores: USA | UK | Canada | Italy | Kindle | UK Kindle By Fabio Claudio Ferracchiati, Emanuele Garofalo ISBN: 1430233710 Publisher: Apress Publication date: May 26, 2011 Binding: Paperback Estimated price: $22.99 Share this book on Twitter |Facebook

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This is a heads up for my readers who are interested in Big Data. Follow these steps to learn Hadoop and get a chance to win a trip to Las Vegas:

1. Register with Big Data University.
2. Enroll and complete the free Hadoop Fundamentals I course.
3. You’ll receive a certificate of completion and an invitation to partecipate in the first Hadoop Programming Challenge.
4. On October 3rd, three participants to this challenge will be selected for a free, all expenses paid, trip to Information on Demand (IOD) 2011 in Las Vegas on October 23rd – 27th.

Best of luck to you.

(Hat tip to Free DB2)

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Among many other fields, the table Customers includes a column name defined as VARCHAR. name is used to store company names.

One of the requirements for the project was to implement a Google Suggest-like feature. That is, when the user enters a few characters for the customer’s name, they should be prompted, via AJAX, with a list of possible suggestions containing that string (or at least beginning with that string.)

The naive approach would be to use a simple LIKE predicate, to generate queries such as:

SELECT name
FROM   Customers
WHERE  name LIKE '%micro%'
ORDER  BY name

One of the main problems with this approach is performance. Using LIKE this way doesn’t allow us to take advantage of indexes that are defined on the column name.

Unsurprisingly, on a modest server, such a query takes about 25 seconds. A UI that isn’t able to respond for 25 seconds will feel like an eternity for the end user, of course, so a simple query like this obviously cannot be seen as a viable solution.

Enter DB2 Text Search. You may be familiar with other full text search engines such as Ferret, Lucene, or Sphinx. DB2 V9.7.4 ships with an extremely powerful full text search engine that has plenty of useful features, including excellent integration with native XML columns.

Using the free edition of DB2 (DB2 Express-C) which includes Text Search, we were able to implement the autocomplete functionality we were after in a heartbeat, thanks to a query like the following:

SELECT name
FROM   Customers
WHERE  CONTAINS(name, 'micro') = 1
ORDER  BY name

This query was executed in mere fractions of a second for most searches, and behaved exactly as needed. In fact, not only did we match strings that began with the searched token, but also ones that contained it elsewhere (e.g., micro would match both Microsoft and Sun Microsystems.) The results where ordered alphabetically, but could have easily been ordered by relevance via the SCORE function, also available via DB2 Text Search.

As usual, it’s a matter of using the right tool for the right job, and DB2 Text Search was created exactly for these kind of scenarios.

Let’s briefly look at how you can also go about setting up and playing with it on Linux.

Installing DB2 Text Search

To start with, you’ll need to have a 64bit Linux distro, and then follow these simple steps.

Download DB2 Express-C. Make sure you grab the db2exc_974_LNX_x86_64.tar.gz file and not the Light edition.

Next, install DB2 by following these steps (the Installing DB2 section in particular.) Make sure you select a custom installation, and that you select everything including DB2 Text Search (which is not checked by default).

After you’ve started DB2 with db2start via the instance user (e.g., db2inst1,) launch the text search server by running:

db2ts start for text

To enable text search for an existing database, run:

db2ts enable database for text connect to mydb

Next, you’ll need to create a text search index and populate it. For example:

db2ts "create index customer_name for text on customers(name) connect to mydb"
db2ts "update index customer_name for text connect to mydb"

That’s it. From now on you’ll be able to use functions such as CONTAINS to quickly search for your data.

Such a function can also be easily invoked in Rails:

Customer.where("CONTAINS(name, ?) = 1", name)

Or wrapping it a little in a model:

class Customer < ActiveRecord::Base
  # ... 
  def self.search(name, max_res = 10)
    where('CONTAINS(name, ?) = 1', name).
    order('name').
    limit(max_res)
  end
end

Which can then be invoked as follows:

Customer.search("micro")

(Technically we wouldn’t have needed limit, so long as we passed RESULTLIMIT to the CONTAINS function.)

You can read more about DB2 Text Search at the Information Center.

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I would argue however that it is far from actually being necessity. For many programming jobs, a computer science education is akin to having a mechanical engineering degree when working as an auto mechanic. You’ll certainly have a great understanding of the job you are doing, but a good deal of what you learned academically will fail to resonate with what you do in your day job at the body shop.

What the programming world needs is good, reputable vocations schools. Such institutions should take an extremely hands-on approach, be taught by veterans in the field, and prepare students for how to actually program in the real world from day one.

Focus on SVN and Git, rather than on Petri nets. Teach students how to name identifiers in their code, how to organize code, how to test, how to work with Unicode, how to develop desktop, web, and mobile applications, how to write secure code, how to sell software, how to bill clients, and other software engineering best practices. Give priority to practical topics aided by plenty of exercises and useful projects that represent the kind of work students will one day find themselves doing for an employer.

This type of school may not give us a modern day Turing, but it would definitely help establish a new generation of competent craftspeople who can begin building useful products in the real world before they’ve even donned their mortarboards. And it could easily be a 2 year crash course, rather than 4 years.

I think such an approach would be a huge improvement over the status quo of far too many Computer Science graduates who can’t write a decent program after four years of theory based education (not to mention that they are still indebted years after their graduation).

Assuming that the instructors and material were both great and not your typical “Java school” curriculum, I would recommend this route to most of the people I know who are considering getting into this field.

What do you think?

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Recently Code School released their second course, which is devoted to jQuery (it’s currently on sale for $45, and is also available as a bundle with their earlier Rails course). The unusual name, jQuery Air, comes from the fact the course’s theme is airplanes.

The course starts with the basics of JavaScript; it doesn’t explore this area exhaustively, instead it tries to cover just enough ground to quickly move onto the actual jQuery material. This early phase focuses on the history of JavaScript, basic data structures like numbers, strings, arrays, and maps, as well as how to use named and anonymous functions.

The rest of the course covers everything you’d expect it to (such as DOM querying and manipulation, element visibility, timing issues, transitions, and animations). There’s also a bit of AJAX tossed in at the end for good measure, but not really enough to call it a topic that this course covers with any degree of detail.

Jeff Casimir is a fun, confident teacher with a clear, easy to understand style. He introduces you to some of the best practices as you write JavaScript and jQuery code, always reminding course participants about the separation of concerns/responsibilities when it comes to HTML, CSS, and JavaScript.

No bones about it, this is the best introduction to jQuery I’ve encountered. In few hours you’ll be able to understand how jQuery works, as well as how to take advantage of it for your own web applications.

If you watch the videos and work on the challenges tonight, you’ll be ready to work with jQuery by tomorrow morning. You won’t become an expert overnight, but you certainly shouldn’t be be leery of the DOM either. This course sets outs a very solid foundation upon which you can easily continue to build and further your knowledge of, and experience with, JavaScript and jQuery.

These days jQuery has become the de facto library for JavaScript development on the web, and learning it is now paramount for most web developers. Worth noting as well is that jQuery is also going to be the default library for Rails 3.1, thus making it of even greater relevance to many of this site’s readers.

As a prize for completing the challenges you’ll get a free screencast from Peepcode. I went with the CoffeeScript one, given that this will also be included by default in Rails 3.1.

Buy this great course now, thank me later.

I truly look forward to seeing further installments of this jQuery series, as well as more advanced courses that cover different languages and technologies.

Disclaimer: I received a review copy of the course. The links to Code School contain my referral id. Theses points do not affect in any way my judgment of what is, indisputably, an outstanding introduction to jQuery.

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In this brief tutorial I’ll show you how to create a complete Python and Django setup for DB2 on Ubuntu. By following my step-by-step instructions, you’ll be able to install the following components:

• Python
• easy_install
• Django
• DB2 Express-C 9.7.4
• The official Python driver, dbi module, and Django adapter for DB2

Installing Python and easy_install

Technically Python is already installed on Ubuntu, so we don’t have to install it. However, we need the python-dev package in order to build the DB2 driver from source. We’ll also need easy_install which is included in the python-setuptools Ubuntu .deb:

$ sudo apt-get install python-dev python-setuptools

Installing Django

Now that we have easy_install available, we can easily install Django by running:

$ sudo easy_install django

You can verify the installed version by running:

$ python

And then executing the following snippet in the REPL:

>>> import django
>>> django.VERSION
(1, 3, 0, 'final', 0)

At this time, version 1.3.0 should get installed as shown above.

Installing DB2

We can now download and install DB2 Express-C 9.7.4. Download the .tar.gz file to a location that’s convenient for you. Then proceed to unpack it:

$ cd ~/Downloads/
$ tar xvfz db2exc_974_LNX_x86.tar.gz
$ cd expc

We’ll install one required library and then proceed with the setup:

$ sudo apt-get install libaio1
$ sudo ./db2setup

Follow the GUI wizard on screen to continue with the installation. Pay close attention to two steps:

• When prompted select a custom installation, and when choosing the components, select all of them. We’ll need the Application Development Tools in order to build the Python driver later on (and these are unchecked by default).
• When asked if you’d like to create an instance user, go with that option. It greatly simplifies the setup process.

When the setup of DB2 is completed, you should receive a confirmation message informing you about the successful installation

For good measure, add the following line to your ~/.bashrc file:

. /home/db2inst1/sqllib/db2profile

This ensures that even your regular, non-DB2, user will be able to connect and interact with the database.

Installing the Python driver and Django adapter

The last step we need to take is to install the ibm_db Python driver and the ibm_db_dbi module, as well as the Django adapter for DB2. These are all IBM supported, open source releases.

Open a new shell and run:

$ sudo -s
$ export IBM_DB_DIR=/home/db2inst1/sqllib
$ export IBM_DB_LIB=/home/db2inst1/sqllib/lib
$ . /home/db2inst1/sqllib/db2profile
$ easy_install ibm_db ibm_db_django
$ exit

A quick sanity test

To ensure that all is well with your setup, run the following command:

$ django-admin.py startproject db2test
$ cd db2test

Now edit settings.py so ENGINE is set to ibm_db_django, NAME to a database like db2test, USER to db2inst1, PASSWORD to the same password you specified for the db2inst1 user during the installation of DB2. Use localhost for the HOST, and 50000 as the port number:

DATABASES = {
    'default': {
        'ENGINE': 'ibm_db_django',
        'NAME': 'db2test',
        'USER': 'db2inst1',
        'PASSWORD': 'secret',
        'HOST': 'localhost',
        'PORT': '50000',
    }
}

Create the database db2test by running:

$ su - db2inst1
$ db2start
$ db2 create db db2test
$ exit

Depending on your hardware specs, the infrequent operation of creating a database can take a bit of time (e.g., several minutes).

We will now run the actual test:

$ python manage.py test

Unless exceptions are raised during this last step, you should be all set to use Django with DB2.

If you need help

IBM is the only database vendor to officially provide and support its Python driver and Django adapter. While commercial DB2 support is available and relatively inexpensive, your first line of defense is posing your questions in the support forum over at Google. Alternatively, if the question is DB2-specific and not related to Python/Django, you can use the DB2 Express-C forum over at developerWorks instead.

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• Ruby 1.8.7
• Rubygems
• Ruby on Rails
• DB2 Express-C 9.7.4
• The official Ruby driver and Rails adapter for DB2

Installing Ruby

We are going to install Ruby 1.8.7 using the Debian packages that are available in the default repositories:

$ sudo apt-get install ruby-full

Next we’ll build Rubygems from scratch, so as to obtain a recent version and be able to update it to the latest one via the gem system itself:

$ cd /tmp/
$ wget http://production.cf.rubygems.org/rubygems/rubygems-1.7.2.tgz
$ tar xvfz rubygems-1.7.2.tgz
$ cd rubygems-1.7.2
$ sudo ruby setup.rb
$ sudo gem update --system

You can now verify that Rubygems is correctly installed:

$ gem -v
1.8.1

Note: If you plan to have multiple versions of Ruby, you’ll probably want to look into RVM.

Installing Rails

We are not going to install the Rails package that ships with Ubuntu, because this is also quite obsolete at this stage. Instead, we’ll use the newly installed gem command:

$ sudo gem install rails

(Add the --no-rdoc --no-ri flags if you don’t care about the local documentation. This will speed up the installation process.)

You can verify the installed version by running:

$ rails -v
Rails 3.0.7

Installing DB2

We can now download and install DB2 Express-C 9.7.4. Download the .tar.gz installation file to a location that’s convenient for you. Then proceed to unpack it:

$ cd ~/Downloads/
$ tar xvfz db2exc_974_LNX_x86.tar.gz
$ cd expc

We’ll install one required library and then proceed with the setup:

$ sudo apt-get install libaio1
$ sudo ./db2setup

Follow the GUI wizard on screen to continue with the installation. Pay close attention to two steps:

• When prompted select a custom installation, and when choosing the components, select all of them We’ll need the Application Development Tools in order to build the Ruby driver later on. (And these are unchecked by default.)
• When asked if you’d like to create an instance user, go with that option. It greatly simplifies the setup process.

When the setup of DB2 is completed, you should receive a confirmation message informing you about the successful installation.

For good measure, add the following line to your ~/.bashrc file:

. /home/db2inst1/sqllib/db2profile

This ensures that even your regular, non-DB2, user will be able to connect and interact with the database.

Installing the ibm_db gem

The last step we need to take is to install the ibm_db gem, which includes the IBM released (and supported) open source driver for Ruby, as well as the adapter for Rails. You’ll need these in order to use Rails with DB2.

Open a new shell and run:

$ sudo -s
$ export IBM_DB_INCLUDE=/home/db2inst1/sqllib/include
$ export IBM_DB_LIB=/home/db2inst1/sqllib/lib
$ . /home/db2inst1/sqllib/db2profile
$ gem install ibm_db
$ exit

At the time of writing, this installs ibm_db-2.5.6.

A quick sanity test

To ensure that all is well with your setup, run the following command:

$ rails new db2test -d ibm_db
$ cd db2test

Now, edit config/database.yml so that the development section uses the same password you specified for the db2inst1 user during the installation of DB2. Change the database name to something like db2test. The section should look like the example below:

development:
	adapter: ibm_db
	username: db2inst1
	password: secret
	database: db2test

Create the database db2test by running:

$ su - db2inst1
$ db2start
$ db2 create db db2test
$ exit

Depending on your hardware specs, the infrequent operation of creating a database can take quite a long time (e.g., minutes).

We will now install/attach the required gems for this project:

$ bundle install

For the sake of a quick example, we’ll use scaffold to generate some super-basic code. We’ll then run migrations, and the built-in web server:

$ rails g scaffold Subject name:string
$ rake db:migrate
$ rails s

Visit http://localhost:3000/subjects and you should see a scaffold interface you can use to create, edit, show, and destroy subjects, as I’ve done in the screenshot below.

Note: As you develop, you’ll probably want to use a better web server such as mongrel, unicorn, or thin. You can easily do so by editing your Gemfile and installing the gem via bundle.

Getting help

IBM is the only database vendor to officially provide and support its Ruby driver and Rails adapter. While commercial 24/7 DB2 support is certainly available and relatively inexpensive (i.e., cheaper than MySQL), your first line of defense is posing your questions in the support forum over at Rubyforge. Alternatively, if the question is DB2-specific and not related to Ruby or Rails, you can use the DB2 Express-C forum over at developerWorks instead.

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In the startup world we often debate the merit of ideas vs execution. In this particular case, the idea behind this product is pretty straightforward. It’s a video course about common idioms and best practices in Rails, that helps you learn how to refactor bad Rails code/anti-patterns/habits into good ones.

Click to enlarge

As is often the case, the implementation is what makes this course really worthwhile. It’s Khan Academy meets Rails (and Khan Academy truly is the future of education).

Rails Best Practices provides a series of small videos that show examples of common bad code that may be used when trying to resolve a particular problem, then they introduce a refactoring that uses best practices to make the code a lot better.

In the process, these videos end up introducing some of the latest tools and features that are available in Rails 3. So if you haven’t made the switch yet from Rails 2 to Rails 3, you’ll find the videos particularly interesting.

This course isn’t just a collection of well produced videos and downloadable slides though. It’s dived into five levels, akin in that regard to a video game. To proceed to the next level, you need to correctly complete and submit all of the exercises for the current level. Each exercise will award you 250 points.

While working on very practical exercises, you’ll be able to reference the videos and re-watch them as often as you please. You’re also able to make mistakes and then see the exceptions that are raised by Ruby.

Click to enlarge

When you complete a level, you’re awarded a badge. As well you’ll receive a few bonuses once you’ve completed the whole course (including a free peepcode.com screencast, $5 codeschool.com credit towards your next purchase, and 35% off all books at InformIT).

I’m a firm believer that the approach to learning in which one is taught by doing exercises in a game-like setting is a highly effective way to help retain the material you’ve has studied. (I should mention that there is a support forum as well, just in case you’re stuck or need some help.)

At $75, this course isn’t exactly a bargain basement deal, however it’s currently on sale for a considerably more wallet friendly $45, and you’ll definitely get your money’s worth if you are a Rails developer.

In conclusion, given that levels are not visible until you pass them, here is the complete table of content, including all the levels, for this course.

Level 1 & 2

• Skinny Controller, Fat Model
• Scope it out
• Fantastic Filters
• Nested Attributes
• Models without the DB
• Really REST
• Enter the Presenters
• Memoization
• Reject SQL Injection
• Rails 3 Responder Syntax

Level 3 and 4

• Loving your Indices
• Protecting your Attributes
• Default Values
• Proper use of Callbacks
• Sowing the Seeds
• N + 1 is not for fun
• Counter Cache Money
• Batches of Find Each
• Law of Demeter
• to_s & to_param

Level 5

• No Queries in your View
• Helper Skelter
• Partial Sanity
• Empty String Things
• Yield to the content_for
• Meta Yield
• Rock your Block Helpers

All in all, I was very pleased with this enjoyable course, and I think that beginner to intermediate Rails developers are the ones who stand to get the most out of it.

Full disclosure: I was granted access to the course for free, and the link to the course contains my affiliate id. Nevertheless, everything above is my frank and honest opinion.

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• Radiant CMS is a popular, easy to use open source Content Management System (CMS) that’s written in Ruby on Rails.
• DB2 Express-C is a fully functional, free edition of DB2 which can be used in production for commercial purposes.
• Cloud, in this particular context, refers to Amazon Web Services (AWS) that are managed with the aid of RightScale (an excellent Cloud management platform).

Prerequisites

In order to run Radiant and DB2 in the Cloud and follow this tutorial, you’ll need to register with both Amazon Web Services and RightScale. You will also need to explicitly provide your AWS credentials to RightScale in order to manage Amazon’s services. If you haven’t taken these steps already, you can follow this short screencast to learn how to do so now.

Introduction to RightScale ServerTemplates

Rather than setting up the whole deployment stack from scratch, when using RightScale you can use special templates called RightScale ServerTemplates. These will take care of installing the required stack for you, thereby saving you time – and a possible headache, too.

IBM provides a RightScale ServerTemplate for your convenience called “Radiant CMS on IBM DB2 Express-C”, which installs Apache, Rails, Radiant, and DB2 on CentOS. Thanks to this template, it’s possible to have a Radiant and DB2 stack running in the Cloud in just a few minutes. This tutorial will show you how.

Creating a security group

Before adding a server to our deployment we need to create a security group. This is a set of firewall rules that are used to define which ports are open on the server, as well as which IPs are accepted.

A security group is created within a specific geographical Cloud. For our particular ServerTemplate, the currently supported Clouds are US-East, US-West, EU, and AP-Singapore. AP-Tokyo is likely to be added in the upcoming weeks.

Select a Cloud of your choice (the closest one to you will do) and create a new security group from the Clouds menu as shown in the figure below.

Creating a security group

You’ll be asked to provide a name for the group. It’s best to call it something meaningful, such as DB2 Public Access or Default Web Access. When prompted, you should open port 80 (for the web server) and port 50000 (for DB2), but you may want to enable port 22 as well for SSH access (admittedly not quite a best practice, but let’s keep things simple and standard), and any other port you think you may need. In the input mask, use 0.0.0.0/0 to indicate that all IPs are accepted for such ports.

Opening port 80

Adding a server to a deployment

The first step will be importing IBM’s template in our RightScale account from the RightScale public Library. You can always find a link to said library by clicking on the Design menu and then on Library. There you’ll be able to search and browse all of the available templates. For your convenience, here’s a link you can click to bring you directly to the Radiant CMS on IBM DB2 Express-C template.

Click import and you’ll be prompted with a DB2 Express-C licensing agreement. Read it through (cough) and if you agree with the terms, click the accept check box and then Finish. The ServerTemplate will be imported for you, as shown in figure below.

An imported server

At this point, you can click Add To Deployment and select one of the available Clouds that are close to you (e.g., AWS US-East). Select the same Cloud you picked when creating a security group and then click Continue.

In the new popup dialog, you can select several parameters like Deployment, MultiCloud Image, Nickname, and so on. You can leave all the defaults on, but you should specify an Instance Type and Security Group(s). The former indicates what type of EC2 instance you need for your server (e.g., a micro instance), while the latter should be the security group (or groups) you created earlier on.

Keep in mind that Amazon will charge you based on an hourly basis, as well as depending on the instance type and Cloud you chose. A micro instance on the US-East Cloud as per this example is the cheapest solution. (Amazon even allows new customers to obtain a micro instance for free for the first year.)

You will be redirected to the deployment you specified or that was selected by default (the default is unsurprisingly called Default). From this deployment you’ll be able to administer your instance of the server. (Note: You can always access your deployments from the Manage -> Deployments menu link.)

From within the Default deployment, start the server by clicking the triangular blue launch icon on the right side of the screen, which is located on the same line as your server’s nickname.

Launching a server

On the new page that appears, click the Launch button. The server will boot and you’ll be brought back to your deployment. While the server boots, you should see several status update messages that will help keep you in the loop regarding the status of the server.

If all goes well, and depending on your Cloud/instance choices, you should have the server up and running (i.e., the status will be operational) in five minutes or less.

You can now click on the nickname of the server (e.g., Radiant CMS on IBM DB2 Express-C), where you’ll find a clickable link corresponding to the “Public DNS name”. If you click on this link a Radiant CMS installation should appear.

Append /admin to that URL, and you’ll be able to login with the default username (admin) and password (radiant). From there you can experiment and change things as you wish in order to make the site yours. Your changes will be persisted in the database, even if you reboot your instance.

To learn more about how to use Radiant as you play around with it in the Cloud, feel free to consult the official Radiant documentation.

That’s it. Enjoy Radiant CMS and DB2 in the Cloud.

Important notes

Remember to stop your server if you are not using it in production or if you were just experimenting with it and you don’t need it at the moment. Keep in mind that Amazon will charge you for the time you have the server up (unless of course you took advantage of the AWS Free Usage Tier). You can stop a server from the deployment or by clicking the Stop button from the server information page where you found the public DNS name.

If you plan on keeping the server running, you must change your Radiant CMS admin password to a stronger and more secure one. You can do so from /admin, by clicking on the Users link at the top of the page, and then on Administrator.

At this time the ServerTemplate doesn’t allow you to change the password for DB2 users. You must do so manually from the console. It’s important that you change the password for the database/system users db2inst1, dasusr1, and db2fenc1 from ‘password’ to more secure ones. If you don’t take this step, you run the risk of having your server hacked in no time. When you update the password for these three users, you also need to update the /opt/www/blog/config/database.yml file with the password you just changed for the database/system user db2inst1.

You can access a root SSH console for your server from the deployment area (when the server is running a small console icon is visible). Click on this icon, then select the type of console that you want to operate (OpenSSH or Mindterm), and accept the RSA key fingerprint that you’re presented with. As root you can fully manage the server, including changing passwords for users (e.g., passwd db2inst1).

Of course, if you are just demoing or experimenting for 15 minutes, you can probably ignore these password related steps (which are quick, but admittedly more tedious).

If you have any questions, please feel free to ask in the comment section or via email.

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