Advanced Rails : How do you create a New Database from schema.db ?

1. Select your Project

2. Edit config\database.yml
development:
database: SourceDatabaseName

3. Delete schema.db

4. Right-click and select Rake\db\schema\load which basically the same as typing into the Rails Shell

5. Edit config\database.yml
development:
database: ProjectDatabaseName

Nb. Assume that you had already create an empty database for your project

6. rake db:schema:load

That's it, when you check your project database, it is already populated with the Source Schema.

Advanced Rails : Moving an Existing Database to a Rails Application

Assuming that you have an existing application that you wish to rewrite in Rails, how would you prepare your database schema so that you can take advantage of the magick of db:migrate ?

Well, I had to do exactly that when I decided to rewrite an existing 200+tables CRM solution into e-CRM, a Rails application. This is what I did :-

a) Pluralize all the table names

Tip: One legacy table was named customer. To pluralize it to customers whilst retaing the data, I use CREATE TABLE customers SELECT * FROM customer for MySQL

b) Add an id field (auto-increment, integer) to every table

c) Add created_at, updated_at in every table to take advantage of Rails automatic updating of these fields without a single line of code

d) Added another magic column ie lock_version (must default to 0) to invoke optimistic locking

e) To support a belongs_to relationship, add belongs_to_tablename

f) Create a schema_info table with just 1 field ie Version, Integer and add a single record with the value=1

g) Use Rake db:schema:dump to create a schema.rb based on the underlying database schema . See following snapshot of Radrails in action

h) Create an empty migration file say 001_migrate2mysql and copy the contents to the Self.Up Method as shown in the Radrails snapshot as follows :-

That's it !
Updated on 4th November, 2007.

Using Interbase 2007 in Ruby on Rails Project

Joe McGlyn, Director of Product Management at CodeGear has shown the way to use Interbase 2007 in Ruby on Rails as follows :-

Assuming you already have a project, here are the basic steps to modifying a project to work with InterBase as the database...

1. Get the InterBase gem
gem install ibruby

Comments by CCH :
There are a few ways to do this
a) c:\instantrails\ruby\bin >gem install ibruby

b) In Aptana RadRails,
i) call up the Gems Manager from
Windows\show view\Ruby Gems
ii) Within the Gems Manager
- Click Install
- select ibruby Gem

You can then see the progress within the Console Tab

c) In 3rdRail, you can use the Project Commander


2. Get the Rails adapter (from the root dir of your rails app or from the project commander) script/plugin source http://ibruby.rubyforge.org/svn/rails_plugins/trunk/
script/plugin install ibrails_plugin

Comments by CCH
a) Shell to Command prompt and cd to root of your project folder

c:\project_name>ruby script/plugin source http://ibruby.rubyforge.org/svn/rails_plugins/trunk/
c:\project_name>ruby script/plugin install ibrails_plugin

b) Using Aptana Radrals,
i) select the Rails Plugins Tab
ii) select ibruby and click Go

Nb. If ibruby does not show in the list, revert to method (a) :-)

c) In 3rdRail, you can use the Project Commander

NOTE :
You will also need to add these two lines into your Rails
environment.rb file:
# ------ force InterBase support to be added to Rails
# ------ as Rails currently has no way of extending its db
# ------ support apart from a new Rails release!
require 'active_record'
require 'vendor/plugins/ibrails_plugin/lib/ibrails_plugin'
# ------
Ideally these two lines should appear after the line loading
boot.rb which typically looks like this:
require File.join(File.dirname(__FILE__), 'boot')
and before anything else gets done (particularly any
initialization)

3. Assuming you have IB installed, and have the default IB user/pwd enabled you're good to go.
It will even create the database file (within your project directory by default)
Known limitation:Indicies are limited to ~200 characters, depending on how they are composed. This is InterBase, not the integration.

Comments by CCH

Despite religously following the instructions from Joe McGlyn of CodeGear, I have not been able to overcome the barrier and error message
ie "database configuration specifies nonexistent interbase adapter"
You may want to read the thread "Using Interbase with RoR" started by Joe here borland.public.3rdrail.ide