== Version 0.20.0

A bug fix release.

Some notable changes:

* Added better sql injection protection in Og sql stores.

* Fixed Mysql store reconnect bug.

* Og falls back to pure ruby adapters for Mysql and Postgres, to 
	make it easier to run out of the box. Please, don't forget to 
	switch to the natively compiled adapters for production sites.

* :uniq keyword

* fix for self join.

* Many, many, many bug fixes and small improvements. This release
	fixes all reported bugs in the spirit of out zero-bug tolerance
	philosophy.	


== Version 0.19.0 was released on 31/05/2005.

Og reloaded part 2: Another superb release introducing a balanced 
mix of innovative new features, common but useful stuff and bug 
fixes. 

Some notable changes:

* Og polymorphic relations. A groundbreaking feature made possible
	by Og's unique design and Ruby's power. Let's use an example 
	to explain the concept:
	
	class Comment
		...
		belongs_to Object # polymorphic marker
	end
	
	class User
		...
		has_many Comment
	end
	
	class Article
		...
		has_many Comment
	end
	
	u = User.new
	u.comments << User::Comment('Hello')
	
	a = Article.new
	a.comments << Article::Comment('Wow!')
	
	User::Comment and Article::Comment where automatically created
	by Og and are serialized in different tables (also automatically
	created by Og). This is the	next step in DRY!

* Og now supports inheritance using the well known Single Table
	Inheritance pattern. Thanks to Og's advanced design the pattern
	is fully encapsulated:
	
	class Document
		...
		schema_inheritance
	end
	
	class Article < Document
		..
	end
	
	class Photo < Document
		..
	end
	
	Document.all # => includes Articles and Photos
	Article.all # => only Articles
	
	User.documents # => Articles and Photos
	User.documents(:type => Photo) # => only photos.

	Btw, this feature is orthogonal to the polymorphic relations
	feature just described, giving the developer great 
	flexibility.

* Integrated an SQLite3 patch by Ghislain Mary.

* Integrated PostgreSQL binary data patch by Michael Neumann.

* Fixed all reported bugs.


== Version 0.18.0 was released on 01/06/2005.

Mainly a bug fix release. Many small improvements were 
implemented. All reported bugs were fixed, as well as bugs found 
during the deployment of a live application. For more information
consult the detailed changelog. Thanks to Julien Perrot for small
patches.

Some notable changes:

* Thread safe mode was added again in Og. This works nice with
	the Webrick server.
	
* New order macro in Og to set default ordering for each
	entity. The has_many collections respect the order setting.

* Fixes in the SQLite adapter.

* No warnings in the Posrgres adapter.
	
* Cleaned up some source files.


== Version 0.17.0 was released on 16/05/2005.

Og Reloaded!! A totally new, clean and elegant implementation 
that supports tons of new advanced features. This version should
be considered as a preview, but you really have to *try* this! 
A new version, with the rest of the planned features and bug
fixes is expected shortly. Many thanks to Michael Neumann and 
the other hackers on the mailing list for ideas and suggestions 
that made this version possible.

Most notable additions:

* Extremely clean source code. Better names are used thorougout.
	Extra care was taken to make all features more orthogonal.
	
* Brand new relation mechanism. The 'enchanting' of entities 
	(managed classes) happens in multiple passes to be more
	flexible. Totaly separated graph/metadata creation and serialization
	code generation. The Graph metadata can be used for advanced
	scaffolding, testing and more.

* Support for fully customizable primary keys. You are no longer
	forced to use xxx_oid primary keys. Appart from the extra 
	flexibility this feature provides this is an essential step
	towards the planed 'reverse engineering' mode that will allow the
	use of existing schemas with Og.
	
* More elegant inspection mechanism. Example:

	Article.relation(:user) # => Og::BelongsTo(...)
	Article.relations # => [...]
	Article.properties # => [...]

* Joins_many relation, as an alias for one way, join table relations.

* Support for 'active' collections. Active collection are
	synchronized with the backend Store and provide a more elegant
	interface and the opportunity for 'session' caching:
	
	article.comments << Comment.new
	
	instead of 
	
	article.add_comment(Comment.new) # this is also allowed though.
	
	p article.comments
	p article.comments.size # the results of the first query is cached

* Eager relations.

	comments = Article.comments(:include => User)

	for comment in comments
		p comment.user.name
	end
	
	Elegantly solves the N+1 query problem by using one join
	query.

* No need for forward references when defining relations. Now,
	the following code magically works:
	
	class User
	  has_many Comment # works even though Comment is not defined!
	end
	
	class Comment
		belongs_to User
	end
	 
* Use inflection where possible to infer missing configuration
	options. For example
	
	class Article
		belongs_to User # infects relation name :user
		...
		
* New, lean and mean Store interface. The code needed to teach 
	Og how to  serialize objects to backend store is dramatically
	reduced. The new interface is SQL agnostic, so non SQL-RDBM's 
	stores are possible.
	
* SQL agnostic querying interface, compatible with non-sql 
	Stores. Here is an example:
	
	Article.find(
		:condition => 'hits > 2 AND rate > 3', 
		:order => 'title',
		:offset => 30,
		:limit => 10
	)

* More elegant (and non-sql store compatible) way for selective 
	updates:

	article.title = 'Changed'
	article.hits += 1
	article.update(:title, :hits)

* New, in-memory store that support all features. This is a pure
	ruby solution useful for experimentation. It will also serve
	as the base for the forthcoming madeleine Store implementation.

* Allow for multiple stores in one application. A great example,
	mysql_to_psql is provided. This example uses Og's powerfull
	features to automatically convert a Mysql database to a 
	PostgreSQL database. Database migration was never easier.
	
* Uses the excellent Facets utility collection to further
	clenup and minimize the code.

* Managed classes or Entities should include the EntityMixin
	or extend the Entity class. Example:
	
	class Article < Entity
		..
	end
	
	class Article 
		include EntityMixin
	end
	
	This is done to avoid the Module module like in earlier
	versions of Og. However, Og is can infer the need to include
	the Managed mixin in typical cases:
	
	class Article
		property :title, String 
		# when a property is defined Og automatically converts the
		# class to an Entity
	end
	
	class Article < AnExistingManagedEntity
		# also includes the mixin
		...
		
	class Article
		include AModuleThatDefinesProperties
		...

* Improved support for og_delete interception.

* Support for nested transactions.
	
* Many, many smaller features and changes.
	
Check out the file test/og/tc_store.rb for a demonstration of
the new features. The stores for Oracle and SqlServer are not
converted yet.


== Version 0.16.0 was released on 15/04/2005.

A snapshot of the latest developments. Many, many subtle improvements,
new features and a major cleanup of the source code. 

Most notable additions:

* Aspect Oriented Programming support. This new system
	is used to reimplement features such as Controller filters,
	Og callbacks and Og observers. By using this unified
	system you can now add Observers to controllers and use
	a metalanguage for wraping Og object callbacks:

	class Controller
 		pre :force_login, :where => :prepend
 		wrap Benchmark, :on => :index
 		post :taraa, :on => login
	end
 
	module Timestamped
 		pre :on => :og_insert { |this| this.create_time = Time.now }
		pre :on => :og_update { |this| this.update_time = Time.now }
		pre :on => [:og_insert, :og_update] { |this| this.create_time = Time.now }
	end

	This feature will be used extensivelly  in future versions
	to improve logging, the shaders and more.

* Major cleanup of the source. Converted the N namespace to
	Nitro. 

* Add Og Timestamped mixin.

* Og improvements.

* Improved the Gem installation process.

* Fixed all reported bugs.


== Version 0.15.0 was released on 04/04/2005.

A great release. Many cool new features and tons of subtle 
improvements. We also welcome a new core developer, Anastastios 
Koutoumanos, who started contributing with a new SqlServer adapter.

Most notable additions:

* NestedSets mixin:

  class Comment
		include NestedSets
	end

	or

	class Comment
		include Hierarchical, :method => :nested_sets
	end

	c.add_comment(child_comment)
	c.full_children
	c.direct_children
	c.children
 
	this is a reimplementation of the SqlTraversable mixin
	available in older versions.
 
* New implementation of Orderable mixin:

  class Comment
    property :body, String
		belongs_to :article, Article
    include Orderable, :scope => article
  end

  c.move_higher

  The Orderable mixin uses the :scope parameter to dynamically alter
  the methods appended to the Comment class. 
 
* New SqlServer adapter.

== Version 0.14.0 was released on 18/03/2005.

Many many important fixes, and many small additions
and improvements. Og mixins are introduced with
an experimental List mixin implementation.

Most notable additions:

* Support for objects that participate in list
 (ordering/removal etc)

* Add useful new enchant methods.

* Fixed all user reported bugs.


== Version 0.13.0 was released on 17/03/2005.

A maintenance release. 

Most notable additions:

* Better separated from Nitro.

* Database related validations (validate_unique) etc.

* Emmit warnings on implicit graph changes.

* Many bugfixes.


== Version 0.12.0 was released on 07/03/2005.

A careful blend of new features and subtle improvements
to the existing infrastructure. Some important bugs where
fixed aswell.

Most notable additions:

* Og automatically generates finders for all properties, for
	even easier (and portable) querying:

	class Article
		property :title, :body, String
		property :hits, Fixnum
		property :create_time, Time
	end

	you get the finders:

	Article.find_by_title
	Article.find_by_body
	Article.find_by_hits
	Article.find_by_create_time

	The finders take into account the unique constrain, to return
	an array or just an object as needed.

* Og introduces lifecycle observers to avoid 'poluting' the model
	objects with excess functionality. You can use every object
	as observer (duck typing) or extend from an AR style Observer
	class. The observer callbacks are precompiled in the lifecycle
	methods only if defined, so the perfomance is not affected
	in the general case.

* Fixed Og bug: multiple many_to_many relations with the
	same target class.

* further code cleanup, improved examples and more.


== Version 0.11.0 was released on 28/02/2005.

The platform continues to evolve and now supports the 
the Oracle database out of the box. This version features 
improved documentation, important bug fixes  and many subtle 
improvements to make programming even more enjoyable. Many 
thanks to Matt Bowen for his help with this release.

Most notable additions:
	
* Documentation (doc/og_tutorial.txt, doc/og_config.txt)

* Og Oracle adapter.

* Og provides advanced metadata for the managed objects

	class Article
		property :title, String
		property :body, String
		has_many :comments, Comment
	end

	par = Article.properties_and_relations
	=> [Property(:title), Property(:body), Og::HasMany(:comments)]

	par[2].klass
	=> Comment

	par[2].meta[:linkback]
	=> :article_oid

* Og Typemacros, here is an example:

	def VarChar(size)
		return String, :sql => "NOT NULL VARCHAR(#{size})"
	end

	property :title, VarChar(30)

* Option for faster startup, skip schema check.

* Many small Og improvements and fixes.

WARNING: If you used an earlier version of Og you
may need to drop your database and let Og recreated it
automatically.


== Version 0.10.0 was released on 15/02/2005.

An important release.

Most notable additions:

* Improved Og implementation (cleaner code) and new Og 
  adapter subsystem.

* New SQLite3 Og adapter, improvements in MySQL and PostgreSQL 
	adapters (needs version 1.1.0 of Sqlite3-Ruby).

* Better GemSpec for easier installation by RubyGems.

* Og supports optional typechecking by using property metadata.

* and many more smaller fixes.

WARNING: If you used an earlier version of Og you
may need to drop your database and let Og recreated it
automatically.


== Version 0.9.3 was released on 01/02/2005.

A maintenance release.

Most notable additions:

* Og metalanguage relations insert metadata into 
	the target class, useful for advanced scaffolders.

* Og refer_to meta-language command. 

* Correct handling of booleans.

* Auto-include metalanguage on prop.

* Many bug fixes.


== Version 0.8 was released on 12/01/2005.

A snapshot of the latest code. Cool new features,
many fixes and improvements in older features. Many thanks
to Michael Neumann for giving intelligent suggestions
and finding small bugs.

Most notable additions:

* New automatic validation system:

	class User
		prop_accessor :name, :password, String
		validate_confirmation :password
		validate_length :name, :range => 2..12
	end

	u = User.new(...)
	unless u.valid?
		p u.errors.on(:name)
		p u.errors[:password]
	end

* No global variables in Og. 

* Recoded Og to allow for future support of multiple databases 
	(even on different RDBMS systems) on a single application.

* cleaned up backend code.

* More unit tests.

* Supports Ruby 1.8.2
	

== Version 0.7 was released on 27/12/2004.

A snapshot of the latest code. Many fixes and new features result
in a more mature product. Many thanks to the ruby hackers that sent
suggestions and patches used in this release!

Most notable additions:

* Totaly recoded prop_accessor mechanism, avoids polution of the Module
  class.
* prop_accessors for Modules, allows synthesizing of managed objects
	from Mixins.
* new automatically generated methods in Og.
* MockDatabase leverages the FlexMock object for easier unit testing.


== Version 0.6 was released on 13/12/2004.

This is a preview release, the api for the new features is not 
finalized. This early release gives other developers to offer suggestions
on the final form of those features.

Most notable additions:

* Og many_to_many relations with auto generation of the join table.
* Og has_one relation.


== Version 0.5.0 was released on 21/11/2004.

New standalone version. SQL indices can be defined again.


== Version 0.5.0 was released on 01/11/2004.

Renamed to Og (ObjectGraph) Og combines the best features of Active
Record and NDB. A fully working MySQL adapter is also provided.
Moreover the code base is further cleaned up. Small improvements 
to the application configuration system. This version is integrated
in Nitro.


== Version 0.2 was released on 07-10-2004. 

The sofware is actually usable but not tested in a production environment. 
Comments from the Ruby community are critical in order to fix possible 
bugs and improve the API. Suggestions for missing features are also 
welcome. This version only supports the Postgres Database.


