Its all about Ruby On Rails
active_record
Generating association while generating model
Dec 14th
May be you guys are already aware of, but in Rails 2.2 we can specify belongs_to association while generating model. So if we issue:
script/generate model Post title:string author:belongs_to
We will get a Post model like:
class Post < ActiveRecord::Base belongs_to :author end
Also it will automatically add the foreign key column in the migration.
class CreatePosts < ActiveRecord::Migration
def self.up
create_table :posts do |t|
t.string :title
t.belongs_to :author
t.timestamps
end
end
def self.down
drop_table :posts
end
end
Nothing much but saves some keystrokes. 
ActiveRecord finder: Now we can use hash as conditions
Feb 22nd
Earlier conditions can either be specified as a string or array now in edge rails we can specify hash also. So if we specify conditions as hash then it will generate conditions based on equality with SQL AND.
Example:
User.find(:all, :conditions=>{:first_name => ‘akhil’, :role => ‘admin’})
will generate SQL as “where `first_name` = ‘akhil’ and `role` = ‘admin’”
Also we can have range as condition
Example:
User.find(:all, :conditions => {:access_level => 3..5})
will generate SQL as “where `access_level` BETWEEN 3 AND 5″
This is really helpful modification in ActiveRecord