Multiple Models in One Form

At "The Pragmatic Bookshelf" there is an extract from "Advanced Rails Recipes" by Mike Clark that explains how to properly handle dynamic creation/removal of the dependent models on one form using ajax.

Here is the link Recipe 13.

Handling move from Rails 2.2.2 to 2.3.2 version

As I preffer to work on virtual machines (by the way my personal choice is VMware) I used one of them while getting in touch with Rails. I had version 2.2.2 installed there.
Today I created a new VM for working with Rails and found out that 2.3.2 version of Rails appeared there as a result of installation. New version of Rails arrived :)
Unfortunally I was not able to run any of my demos :(

To fix this issue I started with change in "config/environment.rb" by updating
RAILS_GEM_VERSION = '2.2.2' unless defined? RAILS_GEM_VERSION
to
RAILS_GEM_VERSION = '2.3.2' unless defined? RAILS_GEM_VERSION
Then I had to run "rake rails:update".

Thats it. These two steps brought demos to life :)

Getting Ruby on Rails 2.2.2 working on Windows XP

When installing Rails 2.2.2 I ancountered a problem with sqlite3. Although sqlite3 is a default database used by Rails starting from version 2.2.2 on Windows XP is not such a trivial thing to make it work.

I started by trying to install sqlite3 using gem like this:

gem install sqlite3-ruby

But I got an error:

ERROR: Error installing sqlite3-ruby:
ERROR: Failed to build gem native extension.

C:/ruby/bin/ruby.exe extconf.rb install sqlite3-ruby
checking for fdatasync() in rt.lib... no
checking for sqlite3.h... no

nmake

Microsoft (R) Program Maintenance Utility Version 1.50
Copyright (c) Microsoft Corp 1988-94. All rights reserved.

NMAKE : fatal error U1073: don't know how to make 'ruby.h'
Stop.

The solution is quite strange from my point of view:

1. Download sqlite and sqlitedll from sqlite downloads (by now they are "sqlite-3_6_10.zip" and "sqlitedll-3_6_10.zip").


2. Unzip both archives to Ruby bin folder ("C:\ruby\bin" on my machine). There should be three files: sqlite3.exe, sqlite3.dll and sqlite3.def.


3. Install sqlite-ruby using such a command:
   

   gem install sqlite3-ruby --version 1.2.3

The strange thing is that if you do not use the version parameter installation will be unsuccessfull.