---
body_id: news
title: DataMapper 0.9 To Be Released on 26 May 08
created_at: 2008-05-20T20:11:24-05:00
summary: And you thought that The Great Refactoring was for naught
release_type: important
author: ssmoot, afrench
filter:
- erb
- textile
---
h1. <%= @page.title %>
As of 26 May 2008, DataMapper 0.9 will be ready for the world. It brings with it a massive overhaul of the internals of DataMapper, a shift in terminology, a dramatic bump in speed, improved code-base organization, and support for more than just database data-stores.
This is NOT a backwards compatible release. Code written for DataMapper 0.3 will not function with DataMapper 0.9 due to syntactical changes and library improvements.
REPEAT: This is NOT a backwards compatible release.
<table summary="Sytax Differences" cellspacing="0" cellpadding="0">
<thead>
<tr>
<td colspan="3" class="pointer"><h3 style="text-align:center;">Syntax Differences</h3></td>
</tr>
<tr class="head">
<td width="49%" class="pointer">DataMapper 0.3</th>
<td width="2%" class="pointer"></th>
<td width="49%" class="pointer">DataMapper 0.9</th>
</tr>
</thead>
<tbody>
<tr>
<td>
<% coderay(:lang => "ruby") do -%>
class Post < DataMapper::Base
end<% end %>
</td>
<td class="pointer">
Creating A Class
</td>
<td>
<% coderay(:lang => "ruby") do -%>
class Post
include DataMapper::Resource
end<% end %>
</td>
</tr>
<tr>
<td>
<% coderay(:lang => "ruby") do -%>
# Key was not mandatory
# Automatically added +id+ if missing
#
# Natural Key
property :name, :string, :key => true
#
# Composite Key
property :id, :integer, :key => true
property :slug, :string, :key => true
<% end %>
</td>
<td class="pointer">
Keys
</td>
<td>
<% coderay(:lang => "ruby") do -%>
# keys are now mandatory
property :id, Integer, :key => true
#
# Natural Key
property :slug, String, :key => true
#
# Composite Key
property :id, Integer, :key => true
property :slug, String, :key => true
<% end %>
</td>
</tr>
<tr>
<td>
<% coderay(:lang => "ruby") do -%>
property :title, :string
property :body, :text
property :posted_on, :datetime
property :active, :boolean
<% end %>
</td>
<td class="pointer">
Properties
</td>
<td>
<% coderay(:lang => "ruby") do -%>
property :title, String
property :body, Text
property :posted_on, Datetime
property :active, Boolean
<% end %>
</td>
</tr>
<tr>
<td>
<% coderay(:lang => "ruby") do -%>
has_many :comments
belongs_to :blog
has_and_belongs_to_many :categories
has_one :author
<% end %>
</td>
<td class="pointer">
Associations
</td>
<td>
<% coderay(:lang => "ruby") do -%>
has 0..n, :comments
belongs_to :blog
has n, :categories => :categories_posts
has 1, :author
<% end %>
</td>
</tr>
<tr>
<td>
<% coderay(:lang => "ruby") do -%>
Post.first :order => 'created_at desc'
Post.all
:conditions => ['active = ?', true]
database.query %Q{SELECT 1}
database.execute %Q{UPDATE posts...}
<% end %>
</td>
<td class="pointer">
Finders
</td>
<td>
<% coderay(:lang => "ruby") do -%>
Post.first :order => [:created_at.desc]
Post.all
:conditions => ['active = ?', true]
repository(:default).adapter.query %Q{SELECT 1}
repository(:default).adapter.execute %Q{UPDATE posts...}
<% end %>
</td>
</tr>
<tr>
<td>
<% coderay(:lang => "ruby") do -%>
validates_presence_of :title
validates_numericality_of :rating
validates_format_of :email,
:with => :email_address
validates_length_of :summary,
:within => (1..100)
validates_uniqueness_of :slug
<% end %>
</td>
<td class="pointer">
Validations
</td>
<td>
<% coderay(:lang => "ruby") do -%>
validates_present :title
validates_is_number :rating
validates_format :email,
:as => :email_address
validates_length :summary,
:in => (1..100)
validates_is_unique :slug
<% end %>
</td>
</tr>
<tr>
<td>
<% coderay(:lang => "ruby") do -%>
before_save :categorize
before_create do |post|
# do stuff with post
end
# return false to abort
<% end %>
</td>
<td class="pointer">Callbacks</td>
<td>
<% coderay(:lang => "ruby") do -%>
before :save, :categorize
before :create do
# do stuff with self
end
# throw :halt to abort
<% end %>
</td>
</tr>
</tbody>
</table>
DM-Core now sports over 1,000 specs split between unit tests and full integration tests. If you ever have any questions about syntax, dig into the integration specs first. It's very likely your use-case is represented there.
DataObjects (do_mysql, do_postgres, and do_sqlite3) has gotten a performance rewrite as well, making them up to 40x faster than before in some cases.
h3. Pre-Release Warning
Though DataMapper 0.9 is stable and production ready, it represents a pre-release before 1.0, and as such, is a work in progress. If you come across ANYTHING of concern, hop on "#datamapper":irc://irc.freenode.net/#datamapper or the "mailing list":http://groups.google.com/group/datamapper, or file a bug on our "issue tracker":http://wm.lighthouseapp.com/projects/4819-datamapper. We want to hear from you!
