Merge branch 'master' of http://github.com/rails/rails

57 files changed, 730 insertions, 464 deletions

diff --git a/activerecord/lib/active_record/aggregations.rb b/activerecord/lib/active_record/aggregations.rb
index 45aaea062d..c45400d3d9 100644
--- a/activerecord/lib/active_record/aggregations.rb
+++ b/activerecord/lib/active_record/aggregations.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Aggregations
   module Aggregations # :nodoc:
     extend ActiveSupport::Concern
 
@@ -189,7 +190,7 @@ module ActiveRecord
       #               :constructor => Proc.new { |ip| IPAddr.new(ip, Socket::AF_INET) },
       #               :converter => Proc.new { |ip| ip.is_a?(Integer) ? IPAddr.new(ip, Socket::AF_INET) : IPAddr.new(ip.to_s) }
       #
-      def composed_of(part_id, options = {}, &block)
+      def composed_of(part_id, options = {})
         options.assert_valid_keys(:class_name, :mapping, :allow_nil, :constructor, :converter)
 
         name        = part_id.id2name
@@ -198,9 +199,7 @@ module ActiveRecord
         mapping     = [ mapping ] unless mapping.first.is_a?(Array)
         allow_nil   = options[:allow_nil]   || false
         constructor = options[:constructor] || :new
-        converter   = options[:converter]   || block
-
-        ActiveSupport::Deprecation.warn('The conversion block has been deprecated, use the :converter option instead.', caller) if block_given?
+        converter   = options[:converter]
 
         reader_method(name, class_name, mapping, allow_nil, constructor)
         writer_method(name, class_name, mapping, allow_nil, converter)
diff --git a/activerecord/lib/active_record/associations.rb b/activerecord/lib/active_record/associations.rb
index 9b59266bbc..4caa434fc0 100755..100644
--- a/activerecord/lib/active_record/associations.rb
+++ b/activerecord/lib/active_record/associations.rb
@@ -88,8 +88,8 @@ module ActiveRecord
     end
   end
 
-  # This error is raised when trying to destroy a parent instance in a N:1, 1:1 assosications
-  # (has_many, has_one) when there is at least 1 child assosociated instance.
+  # This error is raised when trying to destroy a parent instance in N:1 or 1:1 associations
+  # (has_many, has_one) when there is at least 1 child associated instance.
   # ex: if @project.tasks.size > 0, DeleteRestrictionError will be raised when trying to destroy @project
   class DeleteRestrictionError < ActiveRecordError #:nodoc:
     def initialize(reflection)
@@ -886,11 +886,13 @@ module ActiveRecord
       # [:validate]
       #   If false, don't validate the associated objects when saving the parent object. true by default.
       # [:autosave]
-      #   If true, always save any loaded members and destroy members marked for destruction, when saving the parent object. Off by default.
+      #   If true, always save the associated objects or destroy them if marked for destruction, when saving the parent object.
+      #   If false, never save or destroy the associated objects.
+      #   By default, only save associated objects that are new records.
       # [:inverse_of]
       #   Specifies the name of the <tt>belongs_to</tt> association on the associated object that is the inverse of this <tt>has_many</tt>
       #   association.  Does not work in combination with <tt>:through</tt> or <tt>:as</tt> options.
-      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional assocations for more detail.
+      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
       #
       # Option examples:
       #   has_many :comments, :order => "posted_on"
@@ -1001,11 +1003,13 @@ module ActiveRecord
       # [:validate]
       #   If false, don't validate the associated object when saving the parent object. +false+ by default.
       # [:autosave]
-      #   If true, always save the associated object or destroy it if marked for destruction, when saving the parent object. Off by default.
+      #   If true, always save the associated object or destroy it if marked for destruction, when saving the parent object.
+      #   If false, never save or destroy the associated object.
+      #   By default, only save the associated object if it's a new record.
       # [:inverse_of]
       #   Specifies the name of the <tt>belongs_to</tt> association on the associated object that is the inverse of this <tt>has_one</tt>
       #   association.  Does not work in combination with <tt>:through</tt> or <tt>:as</tt> options.
-      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional assocations for more detail.
+      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
       #
       # Option examples:
       #   has_one :credit_card, :dependent => :destroy  # destroys the associated credit card
@@ -1103,14 +1107,16 @@ module ActiveRecord
       # [:validate]
       #   If false, don't validate the associated objects when saving the parent object. +false+ by default.
       # [:autosave]
-      #   If true, always save the associated object or destroy it if marked for destruction, when saving the parent object. Off by default.
+      #   If true, always save the associated object or destroy it if marked for destruction, when saving the parent object.
+      #   If false, never save or destroy the associated object.
+      #   By default, only save the associated object if it's a new record.
       # [:touch]
       #   If true, the associated object will be touched (the updated_at/on attributes set to now) when this record is either saved or
       #   destroyed. If you specify a symbol, that attribute will be updated with the current time instead of the updated_at/on attribute.
       # [:inverse_of]
       #   Specifies the name of the <tt>has_one</tt> or <tt>has_many</tt> association on the associated object that is the inverse of this <tt>belongs_to</tt>
       #   association.  Does not work in combination with the <tt>:polymorphic</tt> options.
-      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional assocations for more detail.
+      #   See ActiveRecord::Associations::ClassMethods's overview on Bi-directional associations for more detail.
       #
       # Option examples:
       #   belongs_to :firm, :foreign_key => "client_of"
@@ -1290,7 +1296,9 @@ module ActiveRecord
       # [:validate]
       #   If false, don't validate the associated objects when saving the parent object. +true+ by default.
       # [:autosave]
-      #   If true, always save any loaded members and destroy members marked for destruction, when saving the parent object. Off by default.
+      #   If true, always save the associated objects or destroy them if marked for destruction, when saving the parent object.
+      #   If false, never save or destroy the associated objects.
+      #   By default, only save associated objects that are new records.
       #
       # Option examples:
       #   has_and_belongs_to_many :projects
@@ -2066,7 +2074,7 @@ module ActiveRecord
               unless klass.descends_from_active_record?
                 sti_column = aliased_table[klass.inheritance_column]
                 sti_condition = sti_column.eq(klass.sti_name)
-                klass.send(:subclasses).each {|subclass| sti_condition = sti_condition.or(sti_column.eq(subclass.sti_name)) }
+                klass.descendants.each {|subclass| sti_condition = sti_condition.or(sti_column.eq(subclass.sti_name)) }
 
                 @join << sti_condition
               end
diff --git a/activerecord/lib/active_record/associations/association_collection.rb b/activerecord/lib/active_record/associations/association_collection.rb
index d9903243ce..ddf4ce4058 100644
--- a/activerecord/lib/active_record/associations/association_collection.rb
+++ b/activerecord/lib/active_record/associations/association_collection.rb
@@ -3,6 +3,8 @@ require 'active_support/core_ext/array/wrap'
 
 module ActiveRecord
   module Associations
+    # = Active Record Association Collection
+    #
     # AssociationCollection is an abstract class that provides common stuff to
     # ease the implementation of association proxies that represent
     # collections. See the class hierarchy in AssociationProxy.
@@ -24,10 +26,10 @@ module ActiveRecord
 
       delegate :group, :order, :limit, :joins, :where, :preload, :eager_load, :includes, :from, :lock, :readonly, :having, :to => :scoped
 
-      def select(select = nil, &block)
+      def select(select = nil)
         if block_given?
           load_target
-          @target.select(&block)
+          @target.select.each { |e| yield e }
         else
           scoped.select(select)
         end
@@ -121,7 +123,7 @@ module ActiveRecord
         end
       end
 
-      # Add +records+ to this association.  Returns +self+ so method calls may be chained.  
+      # Add +records+ to this association.  Returns +self+ so method calls may be chained.
       # Since << flattens its argument list and inserts each record, +push+ and +concat+ behave identically.
       def <<(*records)
         result = true
@@ -166,7 +168,7 @@ module ActiveRecord
         reset_target!
         reset_named_scopes_cache!
       end
-      
+
       # Calculate sum using SQL, not Enumerable
       def sum(*args)
         if block_given?
@@ -239,7 +241,7 @@ module ActiveRecord
 
         if @reflection.options[:dependent] && @reflection.options[:dependent] == :destroy
           destroy_all
-        else          
+        else
           delete_all
         end
 
@@ -388,7 +390,11 @@ module ActiveRecord
             begin
               if !loaded?
                 if @target.is_a?(Array) && @target.any?
-                  @target = find_target + @target.find_all {|t| t.new_record? }
+                  @target = find_target.map do |f|
+                    i = @target.index(f)
+                    t = @target.delete_at(i) if i
+                    (t && t.changed?) ? t : f
+                  end + @target
                 else
                   @target = find_target
                 end
@@ -403,6 +409,17 @@ module ActiveRecord
         end
 
         def method_missing(method, *args)
+          case method.to_s
+          when 'find_or_create'
+            return find(:first, :conditions => args.first) || create(args.first)
+          when /^find_or_create_by_(.*)$/
+            rest = $1
+            return  send("find_by_#{rest}", *args) ||
+                    method_missing("create_by_#{rest}", *args)
+          when /^create_by_(.*)$/
+            return create Hash[$1.split('_and_').zip(args)]
+          end
+
           if @target.respond_to?(method) || (!@reflection.klass.respond_to?(method) && Class.respond_to?(method))
             if block_given?
               super { |*block_args| yield(*block_args) }
@@ -514,8 +531,8 @@ module ActiveRecord
         def callbacks_for(callback_name)
           full_callback_name = "#{callback_name}_for_#{@reflection.name}"
           @owner.class.read_inheritable_attribute(full_callback_name.to_sym) || []
-        end   
-        
+        end
+
         def ensure_owner_is_not_new
           if @owner.new_record?
             raise ActiveRecord::RecordNotSaved, "You cannot call create unless the parent is saved"
diff --git a/activerecord/lib/active_record/associations/association_proxy.rb b/activerecord/lib/active_record/associations/association_proxy.rb
index e88618d278..f333f4d603 100644
--- a/activerecord/lib/active_record/associations/association_proxy.rb
+++ b/activerecord/lib/active_record/associations/association_proxy.rb
@@ -2,6 +2,8 @@ require 'active_support/core_ext/array/wrap'
 
 module ActiveRecord
   module Associations
+    # = Active Record Associations
+    #
     # This is the root class of all association proxies:
     #
     #   AssociationProxy
diff --git a/activerecord/lib/active_record/associations/belongs_to_association.rb b/activerecord/lib/active_record/associations/belongs_to_association.rb
index d2f2267e5c..c2a6495db5 100644
--- a/activerecord/lib/active_record/associations/belongs_to_association.rb
+++ b/activerecord/lib/active_record/associations/belongs_to_association.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Belongs To Associations
   module Associations
     class BelongsToAssociation < AssociationProxy #:nodoc:
       def create(attributes = {})
diff --git a/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb b/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb
index f6edd6383c..38454ec242 100644
--- a/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb
+++ b/activerecord/lib/active_record/associations/belongs_to_polymorphic_association.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Belongs To Polymorphic Association
   module Associations
     class BelongsToPolymorphicAssociation < AssociationProxy #:nodoc:
       def replace(record)
diff --git a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
index 7f39a189e4..c989c3536d 100644
--- a/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Has And Belongs To Many Association
   module Associations
     class HasAndBelongsToManyAssociation < AssociationCollection #:nodoc:
       def create(attributes = {})
diff --git a/activerecord/lib/active_record/associations/has_many_association.rb b/activerecord/lib/active_record/associations/has_many_association.rb
index 0464e8ceea..d74fb7c702 100644
--- a/activerecord/lib/active_record/associations/has_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_association.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Has Many Association
   module Associations
     # This is the proxy that handles a has many association.
     #
@@ -109,7 +110,11 @@ module ActiveRecord
           create_scoping = {}
           set_belongs_to_association_for(create_scoping)
           {
-            :find => { :conditions => @finder_sql, :readonly => false, :order => @reflection.options[:order], :limit => @reflection.options[:limit], :include => @reflection.options[:include]},
+            :find => { :conditions => @finder_sql, 
+                       :readonly => false, 
+                       :order => @reflection.options[:order], 
+                       :limit => @reflection.options[:limit], 
+                       :include => @reflection.options[:include]},
             :create => create_scoping
           }
         end
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 5338bb099d..17f850756f 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -2,6 +2,7 @@ require "active_record/associations/through_association_scope"
 require 'active_support/core_ext/object/blank'
 
 module ActiveRecord
+  # = Active Record Has Many Through Association
   module Associations
     class HasManyThroughAssociation < HasManyAssociation #:nodoc:
       include ThroughAssociationScope
diff --git a/activerecord/lib/active_record/associations/has_one_association.rb b/activerecord/lib/active_record/associations/has_one_association.rb
index ea769fd48b..68b8b792ad 100644
--- a/activerecord/lib/active_record/associations/has_one_association.rb
+++ b/activerecord/lib/active_record/associations/has_one_association.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Belongs To Has One Association
   module Associations
     class HasOneAssociation < AssociationProxy #:nodoc:
       def initialize(owner, reflection)
diff --git a/activerecord/lib/active_record/associations/has_one_through_association.rb b/activerecord/lib/active_record/associations/has_one_through_association.rb
index a79bf943d1..fba0a2bfcc 100644
--- a/activerecord/lib/active_record/associations/has_one_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_one_through_association.rb
@@ -1,6 +1,7 @@
 require "active_record/associations/through_association_scope"
 
 module ActiveRecord
+  # = Active Record Has One Through Association
   module Associations
     class HasOneThroughAssociation < HasOneAssociation
       include ThroughAssociationScope
diff --git a/activerecord/lib/active_record/associations/through_association_scope.rb b/activerecord/lib/active_record/associations/through_association_scope.rb
index 1d2f323112..22e1033a9d 100644
--- a/activerecord/lib/active_record/associations/through_association_scope.rb
+++ b/activerecord/lib/active_record/associations/through_association_scope.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Through Association Scope
   module Associations
     module ThroughAssociationScope
 
@@ -91,7 +92,7 @@ module ActiveRecord
 
       # Construct attributes for :through pointing to owner and associate.
       def construct_join_attributes(associate)
-        # TODO: revist this to allow it for deletion, supposing dependent option is supported
+        # TODO: revisit this to allow it for deletion, supposing dependent option is supported
         raise ActiveRecord::HasManyThroughCantAssociateThroughHasOneOrManyReflection.new(@owner, @reflection) if [:has_one, :has_many].include?(@reflection.source_reflection.macro)
 
         join_attributes = construct_owner_attributes(@reflection.through_reflection).merge(@reflection.source_reflection.primary_key_name => associate.id)
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index c117271c71..56e18eced0 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -1,6 +1,7 @@
 require 'active_support/core_ext/enumerable'
 
 module ActiveRecord
+  # = Active Record Attribute Methods
   module AttributeMethods #:nodoc:
     extend ActiveSupport::Concern
     include ActiveModel::AttributeMethods
diff --git a/activerecord/lib/active_record/autosave_association.rb b/activerecord/lib/active_record/autosave_association.rb
index 0dcadfab5f..7517896235 100644
--- a/activerecord/lib/active_record/autosave_association.rb
+++ b/activerecord/lib/active_record/autosave_association.rb
@@ -1,6 +1,8 @@
 require 'active_support/core_ext/array/wrap'
 
 module ActiveRecord
+  # = Active Record Autosave Association
+  # 
   # AutosaveAssociation is a module that takes care of automatically saving
   # your associations when the parent is saved. In addition to saving, it
   # also destroys any associations that were marked for destruction.
@@ -145,12 +147,12 @@ module ActiveRecord
       #   add_autosave_association_callbacks(reflect_on_association(name))
       # end
       ASSOCIATION_TYPES.each do |type|
-        module_eval %{
+        module_eval <<-CODE, __FILE__, __LINE__ + 1
           def #{type}(name, options = {})
             super
             add_autosave_association_callbacks(reflect_on_association(name))
           end
-        }
+        CODE
       end
 
       # Adds a validate and save callback for the association as specified by
@@ -375,7 +377,7 @@ module ActiveRecord
           if association.updated?
             association_id = association.send(reflection.options[:primary_key] || :id)
             self[reflection.primary_key_name] = association_id
-            # TODO: Removing this code doesn't seem to matter…
+            # TODO: Removing this code doesn't seem to matter...
             if reflection.options[:polymorphic]
               self[reflection.options[:foreign_type]] = association.class.base_class.name.to_s
             end
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 3b6ffa46f2..c8795e4496 100755..100644
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -2,6 +2,7 @@ require 'yaml'
 require 'set'
 require 'active_support/benchmarkable'
 require 'active_support/dependencies'
+require 'active_support/descendants_tracker'
 require 'active_support/time'
 require 'active_support/core_ext/class/attribute'
 require 'active_support/core_ext/class/attribute_accessors'
@@ -14,13 +15,17 @@ require 'active_support/core_ext/hash/slice'
 require 'active_support/core_ext/string/behavior'
 require 'active_support/core_ext/kernel/singleton_class'
 require 'active_support/core_ext/module/delegation'
+require 'active_support/core_ext/module/deprecation'
 require 'active_support/core_ext/module/introspection'
 require 'active_support/core_ext/object/duplicable'
 require 'active_support/core_ext/object/blank'
 require 'arel'
 require 'active_record/errors'
+require 'active_record/log_subscriber'
 
 module ActiveRecord #:nodoc:
+  # = Active Record 
+  #
   # Active Record objects don't specify their attributes directly, but rather infer them from the table definition with
   # which they're linked. Adding, removing, and changing attributes and their type is done directly in the database. Any change
   # is instantly reflected in the Active Record objects. The mapping that binds a given Active Record class to a certain
@@ -274,27 +279,17 @@ module ActiveRecord #:nodoc:
     # on to any new database connections made and which can be retrieved on both a class and instance level by calling +logger+.
     cattr_accessor :logger, :instance_writer => false
 
-    def self.inherited(child) #:nodoc:
-      @@subclasses[self] ||= []
-      @@subclasses[self] << child
-      super
-    end
+    class << self
+      def reset_subclasses #:nodoc:
+        ActiveSupport::Deprecation.warn 'ActiveRecord::Base.reset_subclasses no longer does anything in Rails 3. It will be removed in the final release; please update your apps and plugins.', caller
+      end
 
-    def self.reset_subclasses #:nodoc:
-      nonreloadables = []
-      subclasses.each do |klass|
-        unless ActiveSupport::Dependencies.autoloaded? klass
-          nonreloadables << klass
-          next
-        end
-        klass.instance_variables.each { |var| klass.send(:remove_instance_variable, var) }
-        klass.instance_methods(false).each { |m| klass.send :undef_method, m }
+      def subclasses
+        descendants
       end
-      @@subclasses = {}
-      nonreloadables.each { |klass| (@@subclasses[klass.superclass] ||= []) << klass }
-    end
 
-    @@subclasses = {}
+      deprecate :subclasses => :descendants
+    end
 
     ##
     # :singleton-method:
@@ -403,7 +398,7 @@ module ActiveRecord #:nodoc:
 
       delegate :find, :first, :last, :all, :destroy, :destroy_all, :exists?, :delete, :delete_all, :update, :update_all, :to => :scoped
       delegate :find_each, :find_in_batches, :to => :scoped
-      delegate :select, :group, :order, :limit, :joins, :where, :preload, :eager_load, :includes, :from, :lock, :readonly, :having, :to => :scoped
+      delegate :select, :group, :order, :limit, :joins, :where, :preload, :eager_load, :includes, :from, :lock, :readonly, :having, :create_with, :to => :scoped
       delegate :count, :average, :minimum, :maximum, :sum, :calculate, :to => :scoped
 
       # Executes a custom SQL query against your database and returns all the results.  The results will
@@ -725,14 +720,6 @@ module ActiveRecord #:nodoc:
       end
       alias :sequence_name= :set_sequence_name
 
-      # Turns the +table_name+ back into a class name following the reverse rules of +table_name+.
-      def class_name(table_name = table_name) # :nodoc:
-        # remove any prefix and/or suffix from the table name
-        class_name = table_name[table_name_prefix.length..-(table_name_suffix.length + 1)].camelize
-        class_name = class_name.singularize if pluralize_table_names
-        class_name
-      end
-
       # Indicates whether the table associated with this class exists
       def table_exists?
         connection.table_exists?(table_name)
@@ -806,11 +793,11 @@ module ActiveRecord #:nodoc:
       def reset_column_information
         undefine_attribute_methods
         @column_names = @columns = @columns_hash = @content_columns = @dynamic_methods_hash = @inheritance_column = nil
-        @arel_engine = @unscoped = @arel_table = nil
+        @arel_engine = @relation = @arel_table = nil
       end
 
       def reset_column_information_and_inheritable_attributes_for_all_subclasses#:nodoc:
-        subclasses.each { |klass| klass.reset_inheritable_attributes; klass.reset_column_information }
+        descendants.each { |klass| klass.reset_inheritable_attributes; klass.reset_column_information }
       end
 
       def attribute_method?(attribute)
@@ -909,9 +896,9 @@ module ActiveRecord #:nodoc:
         store_full_sti_class ? name : name.demodulize
       end
 
-      def unscoped
-        @unscoped ||= Relation.new(self, arel_table)
-        finder_needs_type_condition? ? @unscoped.where(type_condition) : @unscoped
+      def relation
+        @relation ||= Relation.new(self, arel_table)
+        finder_needs_type_condition? ? @relation.where(type_condition) : @relation
       end
 
       def arel_table
@@ -928,6 +915,31 @@ module ActiveRecord #:nodoc:
         end
       end
 
+      # Returns a scope for this class without taking into account the default_scope.
+      #
+      #   class Post < ActiveRecord::Base
+      #     default_scope :published => true
+      #   end
+      #
+      #   Post.all          # Fires "SELECT * FROM posts WHERE published = true"
+      #   Post.unscoped.all # Fires "SELECT * FROM posts"
+      #
+      # This method also accepts a block meaning that all queries inside the block will
+      # not use the default_scope:
+      #
+      #   Post.unscoped {
+      #     limit(10) # Fires "SELECT * FROM posts LIMIT 10"
+      #   }
+      #
+      def unscoped
+        block_given? ? relation.scoping { yield } : relation
+      end
+
+      def scoped_methods #:nodoc:
+        key = :"#{self}_scoped_methods"
+        Thread.current[key] = Thread.current[key].presence || self.default_scoping.dup
+      end
+
       private
         # Finder methods must instantiate through this method to work with the
         # single-table inheritance model that makes it possible to create
@@ -935,8 +947,8 @@ module ActiveRecord #:nodoc:
         def instantiate(record)
           object = find_sti_class(record[inheritance_column]).allocate
 
-          object.instance_variable_set(:'@attributes', record)
-          object.instance_variable_set(:'@attributes_cache', {})
+          object.instance_variable_set(:@attributes, record)
+          object.instance_variable_set(:@attributes_cache, {})
           object.instance_variable_set(:@new_record, false)
           object.instance_variable_set(:@readonly, false)
           object.instance_variable_set(:@destroyed, false)
@@ -975,7 +987,7 @@ module ActiveRecord #:nodoc:
         def type_condition
           sti_column = arel_table[inheritance_column]
           condition = sti_column.eq(sti_name)
-          subclasses.each{|subclass| condition = condition.or(sti_column.eq(subclass.sti_name)) }
+          descendants.each { |subclass| condition = condition.or(sti_column.eq(subclass.sti_name)) }
 
           condition
         end
@@ -1162,16 +1174,22 @@ module ActiveRecord #:nodoc:
 
         # Works like with_scope, but discards any nested properties.
         def with_exclusive_scope(method_scoping = {}, &block)
-          with_scope(method_scoping, :overwrite, &block)
-        end
+          if method_scoping.values.any? { |e| e.is_a?(ActiveRecord::Relation) }
+            raise ArgumentError, <<-MSG
+New finder API can not be used with_exclusive_scope. You can either call unscoped to get an anonymous scope not bound to the default_scope:
 
-        # Returns a list of all subclasses of this class, meaning all descendants.
-        def subclasses
-          @@subclasses[self] ||= []
-          @@subclasses[self] + @@subclasses[self].inject([]) {|list, subclass| list + subclass.subclasses }
-        end
+  User.unscoped.where(:active => true)
 
-        public :subclasses
+Or call unscoped with a block:
+
+  User.unscoped do
+    User.where(:active => true).all
+  end
+
+MSG
+          end
+          with_scope(method_scoping, :overwrite, &block)
+        end
 
         # Sets the default options for the model. The format of the
         # <tt>options</tt> argument is the same as in find.
@@ -1183,11 +1201,6 @@ module ActiveRecord #:nodoc:
           self.default_scoping << construct_finder_arel(options, default_scoping.pop)
         end
 
-        def scoped_methods #:nodoc:
-          key = :"#{self}_scoped_methods"
-          Thread.current[key] = Thread.current[key].presence || self.default_scoping.dup
-        end
-
         def current_scoped_methods #:nodoc:
           scoped_methods.last
         end
@@ -1440,14 +1453,6 @@ module ActiveRecord #:nodoc:
       # as it copies the object's attributes only, not its associations. The extent of a "deep" clone is
       # application specific and is therefore left to the application to implement according to its need.
       def initialize_copy(other)
-        # Think the assertion which fails if the after_initialize callback goes at the end of the method is wrong. The
-        # deleted clone method called new which therefore called the after_initialize callback. It then went on to copy
-        # over the attributes. But if it's copying the attributes afterwards then it hasn't finished initializing right?
-        # For example in the test suite the topic model's after_initialize method sets the author_email_address to
-        # test@test.com. I would have thought this would mean that all cloned models would have an author email address
-        # of test@test.com. However the test_clone test method seems to test that this is not the case. As a result the
-        # after_initialize callback has to be run *before* the copying of the atrributes rather than afterwards in order
-        # for all tests to pass. This makes no sense to me.
         callback(:after_initialize) if respond_to_without_attributes?(:after_initialize)
         cloned_attributes = other.clone_attributes(:read_attribute_before_type_cast)
         cloned_attributes.delete(self.class.primary_key)
@@ -1460,6 +1465,7 @@ module ActiveRecord #:nodoc:
         end
 
         clear_aggregation_cache
+        clear_association_cache
         @attributes_cache = {}
         @new_record = true
         ensure_proper_type
@@ -1900,6 +1906,7 @@ module ActiveRecord #:nodoc:
     extend ActiveModel::Naming
     extend QueryCache::ClassMethods
     extend ActiveSupport::Benchmarkable
+    extend ActiveSupport::DescendantsTracker
 
     include ActiveModel::Conversion
     include Validations
diff --git a/activerecord/lib/active_record/callbacks.rb b/activerecord/lib/active_record/callbacks.rb
index 44fee12001..637dac450b 100644
--- a/activerecord/lib/active_record/callbacks.rb
+++ b/activerecord/lib/active_record/callbacks.rb
@@ -1,6 +1,8 @@
 require 'active_support/core_ext/array/wrap'
 
 module ActiveRecord
+  # = Active Record Callbacks
+  # 
   # Callbacks are hooks into the lifecycle of an Active Record object that allow you to trigger logic
   # before or after an alteration of the object state. This can be used to make sure that associated and
   # dependent objects are deleted when +destroy+ is called (by overwriting +before_destroy+) or to massage attributes
@@ -234,8 +236,7 @@ module ActiveRecord
 
     included do
       extend ActiveModel::Callbacks
-
-      define_callbacks :validation, :terminator => "result == false", :scope => [:kind, :name]
+      include ActiveModel::Validations::Callbacks
 
       define_model_callbacks :initialize, :find, :only => :after
       define_model_callbacks :save, :create, :update, :destroy
@@ -249,29 +250,6 @@ module ActiveRecord
           send(meth.to_sym, meth.to_sym)
         end
       end
-
-      def before_validation(*args, &block)
-        options = args.last
-        if options.is_a?(Hash) && options[:on]
-          options[:if] = Array.wrap(options[:if])
-          options[:if] << "@_on_validate == :#{options[:on]}"
-        end
-        set_callback(:validation, :before, *args, &block)
-      end
-
-      def after_validation(*args, &block)
-        options = args.extract_options!
-        options[:prepend] = true
-        options[:if] = Array.wrap(options[:if])
-        options[:if] << "!halted && value != false"
-        options[:if] << "@_on_validate == :#{options[:on]}" if options[:on]
-        set_callback(:validation, :after, *(args << options), &block)
-      end
-    end
-
-    def valid?(*) #:nodoc:
-      @_on_validate = new_record? ? :create : :update
-      _run_validation_callbacks { super }
     end
 
     def destroy #:nodoc:
@@ -286,6 +264,7 @@ module ActiveRecord
     end
 
   private
+
     def create_or_update #:nodoc:
       _run_save_callbacks { super }
     end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index 979ed52f4a..c2d79a421d 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -144,7 +144,9 @@ module ActiveRecord
         @connections.each do |conn|
           conn.disconnect! if conn.requires_reloading?
         end
-        @connections = []
+        @connections.delete_if do |conn|
+          conn.requires_reloading?
+        end
       end
 
       # Verify active connections and remove and disconnect connections
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index b9fb452eee..25432e9985 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -304,7 +304,7 @@ module ActiveRecord
               begin
                 record.rolledback!(rollback)
               rescue Exception => e
-                record.logger.error(e) if record.respond_to?(:logger)
+                record.logger.error(e) if record.respond_to?(:logger) && record.logger
               end
             end
           end
@@ -319,7 +319,7 @@ module ActiveRecord
               begin
                 record.committed!
               rescue Exception => e
-                record.logger.error(e) if record.respond_to?(:logger)
+                record.logger.error(e) if record.respond_to?(:logger) && record.logger
               end
             end
           end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
index 7d58bc2adf..7691b6a788 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
@@ -582,6 +582,11 @@ module ActiveRecord
         @base.add_column(@table_name, column_name, type, options)
       end
 
+      # Checks to see if a column exists. See SchemaStatements#column_exists?
+      def column_exists?(column_name, type = nil, options = nil)
+        @base.column_exists?(@table_name, column_name, type, options)
+      end
+
       # Adds a new index to the table. +column_name+ can be a single Symbol, or
       # an Array of Symbols. See SchemaStatements#add_index
       #
@@ -596,6 +601,11 @@ module ActiveRecord
         @base.add_index(@table_name, column_name, options)
       end
 
+      # Checks to see if an index exists. See SchemaStatements#index_exists?
+      def index_exists?(column_name, options = {})
+        @base.index_exists?(@table_name, column_name, options)
+      end
+
       # Adds timestamps (created_at and updated_at) columns to the table. See SchemaStatements#add_timestamps
       # ===== Example
       #  t.timestamps
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index d3499cea72..76b65bf219 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -24,10 +24,53 @@ module ActiveRecord
       # Returns an array of indexes for the given table.
       # def indexes(table_name, name = nil) end
 
+      # Checks to see if an index exists on a table for a given index definition
+      #
+      # === Examples
+      #  # Check an index exists
+      #  index_exists?(:suppliers, :company_id)
+      #
+      #  # Check an index on multiple columns exists
+      #  index_exists?(:suppliers, [:company_id, :company_type])
+      #
+      #  # Check a unique index exists
+      #  index_exists?(:suppliers, :company_id, :unique => true)
+      #
+      #  # Check an index with a custom name exists
+      #  index_exists?(:suppliers, :company_id, :name => "idx_company_id"
+      def index_exists?(table_name, column_name, options = {})
+        column_names = Array.wrap(column_name)
+        index_name = options.key?(:name) ? options[:name].to_s : index_name(table_name, :column => column_names)
+        if options[:unique]
+          indexes(table_name).any?{ |i| i.unique && i.name == index_name }
+        else
+          indexes(table_name).any?{ |i| i.name == index_name }
+        end
+      end
+
       # Returns an array of Column objects for the table specified by +table_name+.
       # See the concrete implementation for details on the expected parameter values.
       def columns(table_name, name = nil) end
 
+      # Checks to see if a column exists in a given table.
+      #
+      # === Examples
+      #  # Check a column exists
+      #  column_exists?(:suppliers, :name)
+      #
+      #  # Check a column exists of a particular type
+      #  column_exists?(:suppliers, :name, :string)
+      #
+      #  # Check a column exists with a specific definition
+      #  column_exists?(:suppliers, :name, :string, :limit => 100)
+      def column_exists?(table_name, column_name, type = nil, options = {})
+        columns(table_name).any?{ |c| c.name == column_name.to_s &&
+                                      (!type                 || c.type == type) &&
+                                      (!options[:limit]      || c.limit == options[:limit]) &&
+                                      (!options[:precision]  || c.precision == options[:precision]) &&
+                                      (!options[:scale]      || c.scale == options[:scale]) }
+      end
+
       # Creates a new table with the name +table_name+. +table_name+ may either
       # be a String or a Symbol.
       #
@@ -205,6 +248,7 @@ module ActiveRecord
       #  remove_column(:suppliers, :qualification)
       #  remove_columns(:suppliers, :qualification, :experience)
       def remove_column(table_name, *column_names)
+        raise ArgumentError.new("You must specify at least one column name.  Example: remove_column(:people, :first_name)") if column_names.empty?
         column_names.flatten.each do |column_name|
           execute "ALTER TABLE #{quote_table_name(table_name)} DROP #{quote_column_name(column_name)}"
         end
@@ -292,7 +336,7 @@ module ActiveRecord
           @logger.warn("Index name '#{index_name}' on table '#{table_name}' is too long; the limit is #{index_name_length} characters. Skipping.")
           return
         end
-        if index_exists?(table_name, index_name, false)
+        if index_name_exists?(table_name, index_name, false)
           @logger.warn("Index name '#{index_name}' on table '#{table_name}' already exists. Skipping.")
           return
         end
@@ -313,7 +357,7 @@ module ActiveRecord
       #   remove_index :accounts, :name => :by_branch_party
       def remove_index(table_name, options = {})
         index_name = index_name(table_name, options)
-        unless index_exists?(table_name, index_name, true)
+        unless index_name_exists?(table_name, index_name, true)
           @logger.warn("Index name '#{index_name}' on table '#{table_name}' does not exist. Skipping.")
           return
         end
@@ -321,7 +365,7 @@ module ActiveRecord
       end
 
       def remove_index!(table_name, index_name) #:nodoc:
-        execute "DROP INDEX #{quote_column_name(index_name)} ON #{table_name}"
+        execute "DROP INDEX #{quote_column_name(index_name)} ON #{quote_table_name(table_name)}"
       end
 
       # Rename an index.
@@ -350,11 +394,11 @@ module ActiveRecord
         end
       end
 
-      # Verify the existence of an index.
+      # Verify the existence of an index with a given name.
       #
       # The default argument is returned if the underlying implementation does not define the indexes method,
       # as there's no way to determine the correct answer in that case.
-      def index_exists?(table_name, index_name, default)
+      def index_name_exists?(table_name, index_name, default)
         return default unless respond_to?(:indexes)
         indexes(table_name).detect { |i| i.name == index_name }
       end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index 4ee9fee4a9..be8d1bd76b 100755..100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -107,7 +107,7 @@ module ActiveRecord
       # REFERENTIAL INTEGRITY ====================================
 
       # Override to turn off referential integrity while executing <tt>&block</tt>.
-      def disable_referential_integrity(&block)
+      def disable_referential_integrity
         yield
       end
 
@@ -142,9 +142,10 @@ module ActiveRecord
         # this should be overridden by concrete adapters
       end
 
-      # Returns true if its safe to reload the connection between requests for development mode.
+      # Returns true if its required to reload the connection between requests for development mode.
+      # This is not the case for Ruby/MySQL and it's not necessary for any adapters except SQLite.
       def requires_reloading?
-        true
+        false
       end
 
       # Checks whether the connection to the database is still active (i.e. not stale).
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index 7c7bc5e292..aa3626a37e 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -219,7 +219,7 @@ module ActiveRecord
 
       # REFERENTIAL INTEGRITY ====================================
 
-      def disable_referential_integrity(&block) #:nodoc:
+      def disable_referential_integrity #:nodoc:
         old = select_value("SELECT @@FOREIGN_KEY_CHECKS")
 
         begin
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index e84242601b..2fe2ae7136 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -216,7 +216,10 @@ module ActiveRecord
         super(connection, logger)
         @connection_parameters, @config = connection_parameters, config
 
+        # @local_tz is initialized as nil to avoid warnings when connect tries to use it
+        @local_tz = nil
         connect
+        @local_tz = execute('SHOW TIME ZONE').first["TimeZone"]
       end
 
       # Is this connection alive and ready for queries?
@@ -372,7 +375,7 @@ module ActiveRecord
         return false
       end
 
-      def disable_referential_integrity(&block) #:nodoc:
+      def disable_referential_integrity #:nodoc:
         if supports_disable_referential_integrity?() then
           execute(tables.collect { |name| "ALTER TABLE #{quote_table_name(name)} DISABLE TRIGGER ALL" }.join(";"))
         end
@@ -606,27 +609,22 @@ module ActiveRecord
         SQL
 
 
-        indexes = []
-
-        indexes = result.map do |row|
+        result.map do |row|
           index_name = row[0]
           unique = row[1] == 't'
           indkey = row[2].split(" ")
           oid = row[3]
 
-          columns = query(<<-SQL, "Columns for index #{row[0]} on #{table_name}").inject({}) {|attlist, r| attlist[r[1]] = r[0]; attlist}
-          SELECT a.attname, a.attnum
+          columns = Hash[query(<<-SQL, "Columns for index #{row[0]} on #{table_name}")]
+          SELECT a.attnum, a.attname
           FROM pg_attribute a
           WHERE a.attrelid = #{oid}
           AND a.attnum IN (#{indkey.join(",")})
           SQL
 
-          column_names = indkey.map {|attnum| columns[attnum] }
-          IndexDefinition.new(table_name, index_name, unique, column_names)
-
-        end
-
-        indexes
+          column_names = columns.values_at(*indkey).compact
+          column_names.empty? ? nil : IndexDefinition.new(table_name, index_name, unique, column_names)
+        end.compact
       end
 
       # Returns the list of all column definitions for a table.
@@ -929,9 +927,8 @@ module ActiveRecord
           # TIMESTAMP WITH ZONE types in UTC.
           if ActiveRecord::Base.default_timezone == :utc
             execute("SET time zone 'UTC'")
-          else
-            offset = Time.local(2000).utc_offset / 3600
-            execute("SET time zone '#{offset}'")
+          elsif @local_tz
+            execute("SET time zone '#{@local_tz}'")
           end
         end
 
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index f295af16f0..0d9a86a1ea 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -6,6 +6,10 @@ module ActiveRecord
     def self.sqlite3_connection(config) # :nodoc:
       parse_sqlite_config!(config)
 
+      unless 'sqlite3' == config[:adapter]
+        raise ArgumentError, 'adapter name should be "sqlite3"'
+      end
+
       unless self.class.const_defined?(:SQLite3)
         require_library_or_gem(config[:adapter])
       end
@@ -24,13 +28,13 @@ module ActiveRecord
 
   module ConnectionAdapters #:nodoc:
     class SQLite3Adapter < SQLiteAdapter # :nodoc:
-      
+
       # Returns the current database encoding format as a string, eg: 'UTF-8'
       def encoding
         if @connection.respond_to?(:encoding)
-          @connection.encoding[0]['encoding']
+          @connection.encoding.to_s
         else
-          encoding = @connection.send(:get_query_pragma, 'encoding')
+          encoding = @connection.execute('PRAGMA encoding')
           encoding[0]['encoding']
         end
       end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb
index deb62e3802..1927585c49 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb
@@ -151,7 +151,7 @@ module ActiveRecord
       # DATABASE STATEMENTS ======================================
 
       def execute(sql, name = nil) #:nodoc:
-        catch_schema_changes { log(sql, name) { @connection.execute(sql) } }
+        log(sql, name) { @connection.execute(sql) }
       end
 
       def update_sql(sql, name = nil) #:nodoc:
@@ -176,15 +176,15 @@ module ActiveRecord
       end
 
       def begin_db_transaction #:nodoc:
-        catch_schema_changes { @connection.transaction }
+        @connection.transaction
       end
 
       def commit_db_transaction #:nodoc:
-        catch_schema_changes { @connection.commit }
+        @connection.commit
       end
 
       def rollback_db_transaction #:nodoc:
-        catch_schema_changes { @connection.rollback }
+        @connection.rollback
       end
 
       # SCHEMA STATEMENTS ========================================
@@ -246,6 +246,7 @@ module ActiveRecord
       end
 
       def remove_column(table_name, *column_names) #:nodoc:
+        raise ArgumentError.new("You must specify at least one column name.  Example: remove_column(:people, :first_name)") if column_names.empty?
         column_names.flatten.each do |column_name|
           alter_table(table_name) do |definition|
             definition.columns.delete(definition[column_name])
@@ -390,17 +391,6 @@ module ActiveRecord
           end
         end
 
-        def catch_schema_changes
-          return yield
-        rescue ActiveRecord::StatementInvalid => exception
-          if exception.message =~ /database schema has changed/
-            reconnect!
-            retry
-          else
-            raise
-          end
-        end
-
         def sqlite_version
           @sqlite_version ||= SQLiteAdapter::Version.new(select_value('select sqlite_version(*)'))
         end
diff --git a/activerecord/lib/active_record/counter_cache.rb b/activerecord/lib/active_record/counter_cache.rb
index 9601ed6afd..999322129a 100644
--- a/activerecord/lib/active_record/counter_cache.rb
+++ b/activerecord/lib/active_record/counter_cache.rb
@@ -1,4 +1,5 @@
 module ActiveRecord
+  # = Active Record Counter Cache
   module CounterCache
     # Resets one or more counter caches to their correct value using an SQL
     # count query.  This is useful when adding new counter caches, or if the
diff --git a/activerecord/lib/active_record/dynamic_finder_match.rb b/activerecord/lib/active_record/dynamic_finder_match.rb
index fa7a19487c..b39b291352 100644
--- a/activerecord/lib/active_record/dynamic_finder_match.rb
+++ b/activerecord/lib/active_record/dynamic_finder_match.rb
@@ -1,4 +1,9 @@
 module ActiveRecord
+
+  # = Active Record Dynamic Finder Match
+  # 
+  # Provides dynamic attribute-based finders such as <tt>find_by_country</tt> 
+  # if, for example, the <tt>Person</tt> has an attribute with that name. 
   class DynamicFinderMatch
     def self.match(method)
       df_match = self.new(method)
diff --git a/activerecord/lib/active_record/dynamic_scope_match.rb b/activerecord/lib/active_record/dynamic_scope_match.rb
index f796ba669a..15f65be6bc 100644
--- a/activerecord/lib/active_record/dynamic_scope_match.rb
+++ b/activerecord/lib/active_record/dynamic_scope_match.rb
@@ -1,4 +1,11 @@
 module ActiveRecord
+
+  # = Active Record Dynamic Scope Match
+  # 
+  # Provides dynamic attribute-based scopes such as <tt>scoped_by_price(4.99)</tt>
+  # if, for example, the <tt>Product</tt> has an attribute with that name. You can
+  # chain more <tt>scoped_by_* </tt> methods after the other. It acts like a named
+  # scope except that it's dynamic.
   class DynamicScopeMatch
     def self.match(method)
       ds_match = self.new(method)
diff --git a/activerecord/lib/active_record/errors.rb b/activerecord/lib/active_record/errors.rb
index cf5ddca2ba..7aa725d095 100644
--- a/activerecord/lib/active_record/errors.rb
+++ b/activerecord/lib/active_record/errors.rb
@@ -1,4 +1,7 @@
 module ActiveRecord
+
+  # = Active Record Errors
+  #
   # Generic Active Record exception class.
   class ActiveRecordError < StandardError
   end
diff --git a/activerecord/lib/active_record/log_subscriber.rb b/activerecord/lib/active_record/log_subscriber.rb
new file mode 100644
index 0000000000..71065f9908
--- /dev/null
+++ b/activerecord/lib/active_record/log_subscriber.rb
@@ -0,0 +1,32 @@
+module ActiveRecord
+  class LogSubscriber < ActiveSupport::LogSubscriber
+    def initialize
+      super
+      @odd_or_even = false
+    end
+
+    def sql(event)
+      name = '%s (%.1fms)' % [event.payload[:name], event.duration]
+      sql  = event.payload[:sql].squeeze(' ')
+
+      if odd?
+        name = color(name, :cyan, true)
+        sql  = color(sql, nil, true)
+      else
+        name = color(name, :magenta, true)
+      end
+
+      debug "  #{name}  #{sql}"
+    end
+
+    def odd?
+      @odd_or_even = !@odd_or_even
+    end
+
+    def logger
+      ActiveRecord::Base.logger
+    end
+  end
+end
+
+ActiveRecord::LogSubscriber.attach_to :active_record
\ No newline at end of file
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb
index 940f825038..4c5e1ae218 100644
--- a/activerecord/lib/active_record/migration.rb
+++ b/activerecord/lib/active_record/migration.rb
@@ -1,4 +1,5 @@
 require 'active_support/core_ext/kernel/singleton_class'
+require 'active_support/core_ext/module/aliasing'
 
 module ActiveRecord
   # Exception that can be raised to stop migrations from going backwards.
@@ -29,11 +30,15 @@ module ActiveRecord
     end
   end
 
-  # Migrations can manage the evolution of a schema used by several physical databases. It's a solution
-  # to the common problem of adding a field to make a new feature work in your local database, but being unsure of how to
-  # push that change to other developers and to the production server. With migrations, you can describe the transformations
-  # in self-contained classes that can be checked into version control systems and executed against another database that
-  # might be one, two, or five versions behind.
+  # = Active Record Migrations
+  # 
+  # Migrations can manage the evolution of a schema used by several physical 
+  # databases. It's a solution to the common problem of adding a field to make
+  # a new feature work in your local database, but being unsure of how to
+  # push that change to other developers and to the production server. With 
+  # migrations, you can describe the transformations in self-contained classes
+  # that can be checked into version control systems and executed against 
+  # another database that might be one, two, or five versions behind.
   #
   # Example of a simple migration:
   #
@@ -47,10 +52,13 @@ module ActiveRecord
   #     end
   #   end
   #
-  # This migration will add a boolean flag to the accounts table and remove it if you're backing out of the migration.
-  # It shows how all migrations have two class methods +up+ and +down+ that describes the transformations required to implement
-  # or remove the migration. These methods can consist of both the migration specific methods like add_column and remove_column,
-  # but may also contain regular Ruby code for generating data needed for the transformations.
+  # This migration will add a boolean flag to the accounts table and remove it 
+  # if you're backing out of the migration. It shows how all migrations have 
+  # two class methods +up+ and +down+ that describes the transformations 
+  # required to implement or remove the migration. These methods can consist
+  # of both the migration specific methods like add_column and remove_column,
+  # but may also contain regular Ruby code for generating data needed for the 
+  # transformations.
   #
   # Example of a more complex migration that also needs to initialize data:
   #
@@ -64,7 +72,9 @@ module ActiveRecord
   #         t.integer  :position
   #       end
   #
-  #       SystemSetting.create :name => "notice", :label => "Use notice?", :value => 1
+  #       SystemSetting.create  :name => "notice", 
+  #                             :label => "Use notice?", 
+  #                             :value => 1
   #     end
   #
   #     def self.down
@@ -72,35 +82,49 @@ module ActiveRecord
   #     end
   #   end
   #
-  # This migration first adds the system_settings table, then creates the very first row in it using the Active Record model
-  # that relies on the table. It also uses the more advanced create_table syntax where you can specify a complete table schema
-  # in one block call.
+  # This migration first adds the system_settings table, then creates the very 
+  # first row in it using the Active Record model that relies on the table. It
+  # also uses the more advanced create_table syntax where you can specify a 
+  # complete table schema in one block call.
   #
   # == Available transformations
   #
-  # * <tt>create_table(name, options)</tt> Creates a table called +name+ and makes the table object available to a block
-  #   that can then add columns to it, following the same format as add_column. See example above. The options hash is for
-  #   fragments like "DEFAULT CHARSET=UTF-8" that are appended to the create table definition.
+  # * <tt>create_table(name, options)</tt> Creates a table called +name+ and 
+  #   makes the table object available to a block that can then add columns to it,
+  #   following the same format as add_column. See example above. The options hash 
+  #   is for fragments like "DEFAULT CHARSET=UTF-8" that are appended to the create 
+  #   table definition.
   # * <tt>drop_table(name)</tt>: Drops the table called +name+.
-  # * <tt>rename_table(old_name, new_name)</tt>: Renames the table called +old_name+ to +new_name+.
-  # * <tt>add_column(table_name, column_name, type, options)</tt>: Adds a new column to the table called +table_name+
+  # * <tt>rename_table(old_name, new_name)</tt>: Renames the table called +old_name+ 
+  #   to +new_name+.
+  # * <tt>add_column(table_name, column_name, type, options)</tt>: Adds a new column 
+  #   to the table called +table_name+
   #   named +column_name+ specified to be one of the following types:
-  #   <tt>:string</tt>, <tt>:text</tt>, <tt>:integer</tt>, <tt>:float</tt>, <tt>:decimal</tt>, <tt>:datetime</tt>, <tt>:timestamp</tt>, <tt>:time</tt>,
-  #   <tt>:date</tt>, <tt>:binary</tt>, <tt>:boolean</tt>. A default value can be specified by passing an
-  #   +options+ hash like <tt>{ :default => 11 }</tt>. Other options include <tt>:limit</tt> and <tt>:null</tt> (e.g. <tt>{ :limit => 50, :null => false }</tt>)
-  #   -- see ActiveRecord::ConnectionAdapters::TableDefinition#column for details.
-  # * <tt>rename_column(table_name, column_name, new_column_name)</tt>: Renames a column but keeps the type and content.
-  # * <tt>change_column(table_name, column_name, type, options)</tt>:  Changes the column to a different type using the same
-  #   parameters as add_column.
-  # * <tt>remove_column(table_name, column_name)</tt>: Removes the column named +column_name+ from the table called +table_name+.
-  # * <tt>add_index(table_name, column_names, options)</tt>: Adds a new index with the name of the column. Other options include
-  #   <tt>:name</tt> and <tt>:unique</tt> (e.g. <tt>{ :name => "users_name_index", :unique => true }</tt>).
-  # * <tt>remove_index(table_name, index_name)</tt>: Removes the index specified by +index_name+.
+  #   <tt>:string</tt>, <tt>:text</tt>, <tt>:integer</tt>, <tt>:float</tt>, 
+  #   <tt>:decimal</tt>, <tt>:datetime</tt>, <tt>:timestamp</tt>, <tt>:time</tt>,
+  #   <tt>:date</tt>, <tt>:binary</tt>, <tt>:boolean</tt>. A default value can be
+  #   specified by passing an +options+ hash like <tt>{ :default => 11 }</tt>. 
+  #   Other options include <tt>:limit</tt> and <tt>:null</tt> (e.g. 
+  #   <tt>{ :limit => 50, :null => false }</tt>) -- see 
+  #   ActiveRecord::ConnectionAdapters::TableDefinition#column for details.
+  # * <tt>rename_column(table_name, column_name, new_column_name)</tt>: Renames
+  #   a column but keeps the type and content.
+  # * <tt>change_column(table_name, column_name, type, options)</tt>:  Changes 
+  #   the column to a different type using the same parameters as add_column.
+  # * <tt>remove_column(table_name, column_name)</tt>: Removes the column named 
+  #   +column_name+ from the table called +table_name+.
+  # * <tt>add_index(table_name, column_names, options)</tt>: Adds a new index 
+  #   with the name of the column. Other options include
+  #   <tt>:name</tt> and <tt>:unique</tt> (e.g. 
+  #   <tt>{ :name => "users_name_index", :unique => true }</tt>).
+  # * <tt>remove_index(table_name, index_name)</tt>: Removes the index specified 
+  #   by +index_name+.
   #
   # == Irreversible transformations
   #
-  # Some transformations are destructive in a manner that cannot be reversed. Migrations of that kind should raise
-  # an <tt>ActiveRecord::IrreversibleMigration</tt> exception in their +down+ method.
+  # Some transformations are destructive in a manner that cannot be reversed. 
+  # Migrations of that kind should raise an <tt>ActiveRecord::IrreversibleMigration</tt> 
+  # exception in their +down+ method.
   #
   # == Running migrations from within Rails
   #
@@ -110,13 +134,15 @@ module ActiveRecord
   #   rails generate migration MyNewMigration
   #
   # where MyNewMigration is the name of your migration. The generator will
-  # create an empty migration file <tt>timestamp_my_new_migration.rb</tt> in the <tt>db/migrate/</tt>
-  # directory where <tt>timestamp</tt> is the UTC formatted date and time that the migration was generated.
+  # create an empty migration file <tt>timestamp_my_new_migration.rb</tt> 
+  # in the <tt>db/migrate/</tt> directory where <tt>timestamp</tt> is the 
+  # UTC formatted date and time that the migration was generated.
   #
   # You may then edit the <tt>self.up</tt> and <tt>self.down</tt> methods of
   # MyNewMigration.
   #
   # There is a special syntactic shortcut to generate migrations that add fields to a table.
+  #
   #   rails generate migration add_fieldname_to_tablename fieldname:string
   #
   # This will generate the file <tt>timestamp_add_fieldname_to_tablename</tt>, which will look like this:
@@ -191,9 +217,10 @@ module ActiveRecord
   #
   # == Using a model after changing its table
   #
-  # Sometimes you'll want to add a column in a migration and populate it immediately after. In that case, you'll need
-  # to make a call to Base#reset_column_information in order to ensure that the model has the latest column data from
-  # after the new column was added. Example:
+  # Sometimes you'll want to add a column in a migration and populate it 
+  # immediately after. In that case, you'll need to make a call to 
+  # <tt>Base#reset_column_information</tt> in order to ensure that the model has the 
+  # latest column data from after the new column was added. Example:
   #
   #   class AddPeopleSalary < ActiveRecord::Migration
   #     def self.up
diff --git a/activerecord/lib/active_record/named_scope.rb b/activerecord/lib/active_record/named_scope.rb
index 3d8f4a030b..c010dac64e 100644
--- a/activerecord/lib/active_record/named_scope.rb
+++ b/activerecord/lib/active_record/named_scope.rb
@@ -4,11 +4,12 @@ require 'active_support/core_ext/kernel/singleton_class'
 require 'active_support/core_ext/object/blank'
 
 module ActiveRecord
+  # = Active Record Named \Scopes
   module NamedScope
     extend ActiveSupport::Concern
 
     module ClassMethods
-      # Returns an anonymous scope.
+      # Returns an anonymous \scope.
       #
       #   posts = Post.scoped
       #   posts.size # Fires "select count(*) from  posts" and returns the count
@@ -18,14 +19,15 @@ module ActiveRecord
       #   fruits = fruits.where(:colour => 'red') if options[:red_only]
       #   fruits = fruits.limit(10) if limited?
       #
-      # Anonymous \scopes tend to be useful when procedurally generating complex queries, where passing
-      # intermediate values (scopes) around as first-class objects is convenient.
+      # Anonymous \scopes tend to be useful when procedurally generating complex
+      # queries, where passing intermediate values (\scopes) around as first-class 
+      # objects is convenient.
       #
-      # You can define a scope that applies to all finders using ActiveRecord::Base.default_scope.
-      def scoped(options = {}, &block)
+      # You can define a \scope that applies to all finders using 
+      # ActiveRecord::Base.default_scope.
+      def scoped(options = nil)
         if options.present?
-          relation = scoped.apply_finder_options(options)
-          block_given? ? relation.extending(Module.new(&block)) : relation
+          scoped.apply_finder_options(options)
         else
           current_scoped_methods ? unscoped.merge(current_scoped_methods) : unscoped.clone
         end
@@ -35,7 +37,7 @@ module ActiveRecord
         read_inheritable_attribute(:scopes) || write_inheritable_attribute(:scopes, {})
       end
 
-      # Adds a class method for retrieving and querying objects. A scope represents a narrowing of a database query,
+      # Adds a class method for retrieving and querying objects. A \scope represents a narrowing of a database query,
       # such as <tt>where(:color => :red).select('shirts.*').includes(:washing_instructions)</tt>.
       #
       #   class Shirt < ActiveRecord::Base
@@ -85,18 +87,22 @@ module ActiveRecord
       #   end
       def scope(name, scope_options = {}, &block)
         name = name.to_sym
+        valid_scope_name?(name)
 
-        if !scopes[name] && respond_to?(name, true)
-          logger.warn "Creating scope :#{name}. " \
-                      "Overwriting existing method #{self.name}.#{name}."
-        end
+        extension = Module.new(&block) if block_given?
 
         scopes[name] = lambda do |*args|
           options = scope_options.is_a?(Proc) ? scope_options.call(*args) : scope_options
 
-          relation = scoped
-          relation = options.is_a?(Hash) ? relation.apply_finder_options(options) : scoped.merge(options) if options
-          block_given? ? relation.extending(Module.new(&block)) : relation
+          relation = if options.is_a?(Hash)
+            scoped.apply_finder_options(options)
+          elsif options
+            scoped.merge(options)
+          else
+            scoped
+          end
+
+          extension ? relation.extending(extension) : relation
         end
 
         singleton_class.send :define_method, name, &scopes[name]
@@ -106,7 +112,15 @@ module ActiveRecord
         ActiveSupport::Deprecation.warn("Base.named_scope has been deprecated, please use Base.scope instead", caller)
         scope(*args, &block)
       end
-    end
 
+    protected
+
+      def valid_scope_name?(name)
+        if !scopes[name] && respond_to?(name, true)
+          logger.warn "Creating scope :#{name}. " \
+                      "Overwriting existing method #{self.name}.#{name}."
+        end
+      end
+    end
   end
 end
diff --git a/activerecord/lib/active_record/nested_attributes.rb b/activerecord/lib/active_record/nested_attributes.rb
index eb9e792dd8..cf8c5aaf84 100644
--- a/activerecord/lib/active_record/nested_attributes.rb
+++ b/activerecord/lib/active_record/nested_attributes.rb
@@ -15,7 +15,7 @@ module ActiveRecord
       self.nested_attributes_options = {}
     end
 
-    # == Nested Attributes
+    # = Active Record Nested Attributes
     #
     # Nested attributes allow you to save attributes on associated records
     # through the parent. By default nested attribute updating is turned off,
@@ -25,6 +25,7 @@ module ActiveRecord
     #
     # The attribute writer is named after the association, which means that
     # in the following example, two new methods are added to your model:
+    # 
     # <tt>author_attributes=(attributes)</tt> and
     # <tt>pages_attributes=(attributes)</tt>.
     #
@@ -132,7 +133,7 @@ module ActiveRecord
     #   member.posts.first.title # => 'Kari, the awesome Ruby documentation browser!'
     #   member.posts.second.title # => 'The egalitarian assumption of the modern citizen'
     #
-    #  Alternatively, :reject_if also accepts a symbol for using methods:
+    # Alternatively, :reject_if also accepts a symbol for using methods:
     #
     #    class Member < ActiveRecord::Base
     #      has_many :posts
@@ -144,7 +145,7 @@ module ActiveRecord
     #      accepts_nested_attributes_for :posts, :reject_if => :reject_posts
     #
     #      def reject_posts(attributed)
-    #        attributed['title].blank?
+    #        attributed['title'].blank?
     #      end
     #    end
     #
@@ -212,7 +213,7 @@ module ActiveRecord
       #   that will reject a record where all the attributes are blank.
       # [:limit]
       #   Allows you to specify the maximum number of the associated records that
-      #   can be processes with the nested attributes. If the size of the
+      #   can be processed with the nested attributes. If the size of the
       #   nested attributes array exceeds the specified limit, NestedAttributes::TooManyRecords
       #   exception is raised. If omitted, any number associations can be processed.
       #   Note that the :limit option is only applicable to one-to-many associations.
@@ -278,7 +279,7 @@ module ActiveRecord
     # Assigns the given attributes to the association.
     #
     # If update_only is false and the given attributes include an <tt>:id</tt>
-    # that matches the existing record’s id, then the existing record will be
+    # that matches the existing record's id, then the existing record will be
     # modified. If update_only is true, a new record is only created when no
     # object exists. Otherwise a new record will be built.
     #
@@ -295,7 +296,9 @@ module ActiveRecord
         assign_to_or_mark_for_destruction(record, attributes, options[:allow_destroy])
 
       elsif attributes['id']
-        raise_nested_attributes_record_not_found(association_name, attributes['id'])
+        existing_record = self.class.reflect_on_association(association_name).klass.find(attributes['id'])
+        assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy])
+        self.send(association_name.to_s+'=', existing_record)
 
       elsif !reject_new_record?(association_name, attributes)
         method = "build_#{association_name}"
@@ -365,11 +368,16 @@ module ActiveRecord
           unless reject_new_record?(association_name, attributes)
             association.build(attributes.except(*UNASSIGNABLE_KEYS))
           end
+
+        elsif existing_records.count == 0 #Existing record but not yet associated
+          existing_record = self.class.reflect_on_association(association_name).klass.find(attributes['id'])
+          association.send(:add_record_to_target_with_callbacks, existing_record) unless association.loaded?
+          assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy])
+
         elsif existing_record = existing_records.detect { |record| record.id.to_s == attributes['id'].to_s }
           association.send(:add_record_to_target_with_callbacks, existing_record) unless association.loaded?
           assign_to_or_mark_for_destruction(existing_record, attributes, options[:allow_destroy])
-        else
-          raise_nested_attributes_record_not_found(association_name, attributes['id'])
+
         end
       end
     end
@@ -389,7 +397,7 @@ module ActiveRecord
       ConnectionAdapters::Column.value_to_boolean(hash['_destroy'])
     end
 
-    # Determines if a new record should be build by checking for
+    # Determines if a new record should be built by checking for
     # has_destroy_flag? or if a <tt>:reject_if</tt> proc exists for this
     # association and evaluates to +true+.
     def reject_new_record?(association_name, attributes)
@@ -405,9 +413,5 @@ module ActiveRecord
       end
     end
 
-    def raise_nested_attributes_record_not_found(association_name, record_id)
-      reflection = self.class.reflect_on_association(association_name)
-      raise RecordNotFound, "Couldn't find #{reflection.klass.name} with ID=#{record_id} for #{self.class.name} with ID=#{id}"
-    end
   end
 end
diff --git a/activerecord/lib/active_record/observer.rb b/activerecord/lib/active_record/observer.rb
index 0ea7fe7365..5f80bd86df 100644
--- a/activerecord/lib/active_record/observer.rb
+++ b/activerecord/lib/active_record/observer.rb
@@ -1,6 +1,8 @@
 require 'active_support/core_ext/class/attribute'
 
 module ActiveRecord
+  # = Active Record Observer
+  #
   # Observer classes respond to lifecycle callbacks to implement trigger-like
   # behavior outside the original class. This is a great way to reduce the
   # clutter that normally comes when the model class is burdened with
@@ -105,8 +107,9 @@ module ActiveRecord
     end
 
     protected
+
       def observed_subclasses
-        observed_classes.sum([]) { |klass| klass.send(:subclasses) }
+        observed_classes.sum([]) { |klass| klass.send(:descendants) }
       end
 
       def observe_callbacks?
diff --git a/activerecord/lib/active_record/persistence.rb b/activerecord/lib/active_record/persistence.rb
index 10788630a5..50166c4385 100644
--- a/activerecord/lib/active_record/persistence.rb
+++ b/activerecord/lib/active_record/persistence.rb
@@ -1,6 +1,8 @@
 module ActiveRecord
+  # = Active Record Persistence
   module Persistence
-    # Returns true if this object hasn't been saved yet -- that is, a record for the object doesn't exist yet; otherwise, returns false.
+    # Returns true if this object hasn't been saved yet -- that is, a record 
+    # for the object doesn't exist in the data store yet; otherwise, returns false.
     def new_record?
       @new_record
     end
@@ -10,7 +12,8 @@ module ActiveRecord
       @destroyed
     end
 
-    # Returns if the record is persisted, i.e. it's not a new record and it was not destroyed.
+    # Returns if the record is persisted, i.e. it's not a new record and it was
+    # not destroyed.
     def persisted?
       !(new_record? || destroyed?)
     end
@@ -69,8 +72,8 @@ module ActiveRecord
       freeze
     end
 
-    # Deletes the record in the database and freezes this instance to reflect that no changes should
-    # be made (since they can't be persisted).
+    # Deletes the record in the database and freezes this instance to reflect 
+    # that no changes should be made (since they can't be persisted).
     def destroy
       if persisted?
         self.class.unscoped.where(self.class.arel_table[self.class.primary_key].eq(id)).delete_all
@@ -80,10 +83,13 @@ module ActiveRecord
       freeze
     end
 
-    # Returns an instance of the specified +klass+ with the attributes of the current record. This is mostly useful in relation to
-    # single-table inheritance structures where you want a subclass to appear as the superclass. This can be used along with record
-    # identification in Action Pack to allow, say, <tt>Client < Company</tt> to do something like render <tt>:partial => @client.becomes(Company)</tt>
-    # to render that instance using the companies/company partial instead of clients/client.
+    # Returns an instance of the specified +klass+ with the attributes of the 
+    # current record. This is mostly useful in relation to single-table 
+    # inheritance structures where you want a subclass to appear as the 
+    # superclass. This can be used along with record identification in 
+    # Action Pack to allow, say, <tt>Client < Company</tt> to do something 
+    # like render <tt>:partial => @client.becomes(Company)</tt> to render that
+    # instance using the companies/company partial instead of clients/client.
     #
     # Note: The new instance will share a link to the same attributes as the original class. So any change to the attributes in either
     # instance will affect the other.
@@ -104,14 +110,15 @@ module ActiveRecord
       save(:validate => false)
     end
 
-    # Updates all the attributes from the passed-in Hash and saves the record. If the object is invalid, the saving will
-    # fail and false will be returned.
+    # Updates all the attributes from the passed-in Hash and saves the record. 
+    # If the object is invalid, the saving will fail and false will be returned.
     def update_attributes(attributes)
       self.attributes = attributes
       save
     end
 
-    # Updates an object just like Base.update_attributes but calls save! instead of save so an exception is raised if the record is invalid.
+    # Updates an object just like Base.update_attributes but calls save! instead
+    # of save so an exception is raised if the record is invalid.
     def update_attributes!(attributes)
       self.attributes = attributes
       save!
@@ -175,7 +182,7 @@ module ActiveRecord
     def reload(options = nil)
       clear_aggregation_cache
       clear_association_cache
-      @attributes.update(self.class.send(:with_exclusive_scope) { self.class.find(self.id, options) }.instance_variable_get('@attributes'))
+      @attributes.update(self.class.unscoped { self.class.find(self.id, options) }.instance_variable_get('@attributes'))
       @attributes_cache = {}
       self
     end
diff --git a/activerecord/lib/active_record/query_cache.rb b/activerecord/lib/active_record/query_cache.rb
index 093c6c1e55..d9f85a4e5e 100644
--- a/activerecord/lib/active_record/query_cache.rb
+++ b/activerecord/lib/active_record/query_cache.rb
@@ -1,6 +1,7 @@
 require 'active_support/core_ext/object/blank'
 
 module ActiveRecord
+  # = Active Record Query Cache
   class QueryCache
     module ClassMethods
       # Enable the query cache within the block if Active Record is configured.
diff --git a/activerecord/lib/active_record/railtie.rb b/activerecord/lib/active_record/railtie.rb
index a32fb7d399..2808e199fe 100644
--- a/activerecord/lib/active_record/railtie.rb
+++ b/activerecord/lib/active_record/railtie.rb
@@ -9,6 +9,7 @@ require "active_model/railtie"
 require "action_controller/railtie"
 
 module ActiveRecord
+  # = Active Record Railtie
   class Railtie < Rails::Railtie
     config.active_record = ActiveSupport::OrderedOptions.new
 
@@ -25,9 +26,6 @@ module ActiveRecord
       load "active_record/railties/databases.rake"
     end
 
-    require "active_record/railties/log_subscriber"
-    log_subscriber :active_record, ActiveRecord::Railties::LogSubscriber.new
-
     initializer "active_record.initialize_timezone" do
       ActiveSupport.on_load(:active_record) do
         self.time_zone_aware_attributes = true
@@ -68,7 +66,6 @@ module ActiveRecord
       unless app.config.cache_classes
         ActiveSupport.on_load(:active_record) do
           ActionDispatch::Callbacks.after do
-            ActiveRecord::Base.reset_subclasses
             ActiveRecord::Base.clear_reloadable_connections!
           end
         end
diff --git a/activerecord/lib/active_record/railties/databases.rake b/activerecord/lib/active_record/railties/databases.rake
index 006e64b115..7882f05d07 100644
--- a/activerecord/lib/active_record/railties/databases.rake
+++ b/activerecord/lib/active_record/railties/databases.rake
@@ -57,7 +57,7 @@ namespace :db do
       end
     rescue
       case config['adapter']
-      when 'mysql'
+      when /mysql/
         @charset   = ENV['CHARSET']   || 'utf8'
         @collation = ENV['COLLATION'] || 'utf8_unicode_ci'
         creation_options = {:charset => (config['charset'] || @charset), :collation => (config['collation'] || @collation)}
@@ -171,6 +171,36 @@ namespace :db do
       ActiveRecord::Migrator.run(:down, "db/migrate/", version)
       Rake::Task["db:schema:dump"].invoke if ActiveRecord::Base.schema_format == :ruby
     end
+
+    desc "Display status of migrations"
+    task :status => :environment do
+      config = ActiveRecord::Base.configurations[Rails.env || 'development']
+      ActiveRecord::Base.establish_connection(config)
+      unless ActiveRecord::Base.connection.table_exists?(ActiveRecord::Migrator.schema_migrations_table_name)
+        puts 'Schema migrations table does not exist yet.'
+        next  # means "return" for rake task
+      end
+      db_list = ActiveRecord::Base.connection.select_values("SELECT version FROM #{ActiveRecord::Migrator.schema_migrations_table_name}")
+      file_list = []
+      Dir.foreach(File.join(Rails.root, 'db', 'migrate')) do |file|
+        # only files matching "20091231235959_some_name.rb" pattern
+        if match_data = /(\d{14})_(.+)\.rb/.match(file)
+          status = db_list.delete(match_data[1]) ? 'up' : 'down'
+          file_list << [status, match_data[1], match_data[2]]
+        end
+      end
+      # output
+      puts "\ndatabase: #{config['database']}\n\n"
+      puts "#{"Status".center(8)}  #{"Migration ID".ljust(14)}  Migration Name"
+      puts "-" * 50
+      file_list.each do |file|
+        puts "#{file[0].center(8)}  #{file[1].ljust(14)}  #{file[2].humanize}"
+      end
+      db_list.each do |version|
+        puts "#{'up'.center(8)}  #{version.ljust(14)}  *** NO FILE ***"
+      end
+      puts
+    end
   end
 
   desc 'Rolls the schema back to the previous version (specify steps w/ STEP=n).'
@@ -194,7 +224,7 @@ namespace :db do
   task :charset => :environment do
     config = ActiveRecord::Base.configurations[Rails.env || 'development']
     case config['adapter']
-    when 'mysql'
+    when /mysql/
       ActiveRecord::Base.establish_connection(config)
       puts ActiveRecord::Base.connection.charset
     when 'postgresql'
@@ -212,7 +242,7 @@ namespace :db do
   task :collation => :environment do
     config = ActiveRecord::Base.configurations[Rails.env || 'development']
     case config['adapter']
-    when 'mysql'
+    when /mysql/
       ActiveRecord::Base.establish_connection(config)
       puts ActiveRecord::Base.connection.collation
     else
@@ -313,7 +343,7 @@ namespace :db do
     task :dump => :environment do
       abcs = ActiveRecord::Base.configurations
       case abcs[Rails.env]["adapter"]
-      when "mysql", "oci", "oracle"
+      when /mysql/, "oci", "oracle"
         ActiveRecord::Base.establish_connection(abcs[Rails.env])
         File.open("#{Rails.root}/db/#{Rails.env}_structure.sql", "w+") { |f| f << ActiveRecord::Base.connection.structure_dump }
       when "postgresql"
@@ -361,7 +391,7 @@ namespace :db do
     task :clone_structure => [ "db:structure:dump", "db:test:purge" ] do
       abcs = ActiveRecord::Base.configurations
       case abcs["test"]["adapter"]
-      when "mysql"
+      when /mysql/
         ActiveRecord::Base.establish_connection(:test)
         ActiveRecord::Base.connection.execute('SET foreign_key_checks = 0')
         IO.readlines("#{Rails.root}/db/#{Rails.env}_structure.sql").join.split("\n\n").each do |table|
@@ -395,7 +425,7 @@ namespace :db do
     task :purge => :environment do
       abcs = ActiveRecord::Base.configurations
       case abcs["test"]["adapter"]
-      when "mysql"
+      when /mysql/
         ActiveRecord::Base.establish_connection(:test)
         ActiveRecord::Base.connection.recreate_database(abcs["test"]["database"], abcs["test"])
       when "postgresql"
@@ -451,7 +481,7 @@ task 'test:prepare' => 'db:test:prepare'
 
 def drop_database(config)
   case config['adapter']
-  when 'mysql'
+  when /mysql/
     ActiveRecord::Base.establish_connection(config)
     ActiveRecord::Base.connection.drop_database config['database']
   when /^sqlite/
diff --git a/activerecord/lib/active_record/railties/log_subscriber.rb b/activerecord/lib/active_record/railties/log_subscriber.rb
deleted file mode 100644
index 31b98bb6ed..0000000000
--- a/activerecord/lib/active_record/railties/log_subscriber.rb
+++ /dev/null
@@ -1,32 +0,0 @@
-module ActiveRecord
-  module Railties
-    class LogSubscriber < Rails::LogSubscriber
-      def initialize
-        super
-        @odd_or_even = false
-      end
-
-      def sql(event)
-        name = '%s (%.1fms)' % [event.payload[:name], event.duration]
-        sql  = event.payload[:sql].squeeze(' ')
-
-        if odd?
-          name = color(name, :cyan, true)
-          sql  = color(sql, nil, true)
-        else
-          name = color(name, :magenta, true)
-        end
-
-        debug "  #{name}  #{sql}"
-      end
-
-      def odd?
-        @odd_or_even = !@odd_or_even
-      end
-
-      def logger
-        ActiveRecord::Base.logger
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index 0e48e229b3..a82e5d7ed1 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -1,12 +1,16 @@
 module ActiveRecord
+  # = Active Record Reflection
   module Reflection # :nodoc:
     extend ActiveSupport::Concern
 
-    # Reflection allows you to interrogate Active Record classes and objects about their associations and aggregations.
-    # This information can, for example, be used in a form builder that took an Active Record object and created input
-    # fields for all of the attributes depending on their type and displayed the associations to other objects.
+    # Reflection allows you to interrogate Active Record classes and objects
+    # about their associations and aggregations. This information can, 
+    # for example, be used in a form builder that took an Active Record object
+    # and created input fields for all of the attributes depending on their type
+    # and displayed the associations to other objects.
     #
-    # You can find the interface for the AggregateReflection and AssociationReflection classes in the abstract MacroReflection class.
+    # You can find the interface for the AggregateReflection and AssociationReflection
+    # classes in the abstract MacroReflection class.
     module ClassMethods
       def create_reflection(macro, name, options, active_record)
         case macro
@@ -43,8 +47,11 @@ module ActiveRecord
         reflections[aggregation].is_a?(AggregateReflection) ? reflections[aggregation] : nil
       end
 
-      # Returns an array of AssociationReflection objects for all the associations in the class. If you only want to reflect on a
-      # certain association type, pass in the symbol (<tt>:has_many</tt>, <tt>:has_one</tt>, <tt>:belongs_to</tt>) for that as the first parameter.
+      # Returns an array of AssociationReflection objects for all the 
+      # associations in the class. If you only want to reflect on a certain 
+      # association type, pass in the symbol (<tt>:has_many</tt>, <tt>:has_one</tt>, 
+      # <tt>:belongs_to</tt>) for that as the first parameter.
+      #
       # Example:
       #
       #   Account.reflect_on_all_associations             # returns an array of all associations
@@ -71,8 +78,9 @@ module ActiveRecord
     end
 
 
-    # Abstract base class for AggregateReflection and AssociationReflection that describes the interface available for both of
-    # those classes. Objects of AggregateReflection and AssociationReflection are returned by the Reflection::ClassMethods.
+    # Abstract base class for AggregateReflection and AssociationReflection that
+    # describes the interface available for both of those classes. Objects of
+    # AggregateReflection and AssociationReflection are returned by the Reflection::ClassMethods.
     class MacroReflection
       attr_reader :active_record
 
@@ -80,13 +88,15 @@ module ActiveRecord
         @macro, @name, @options, @active_record = macro, name, options, active_record
       end
 
-      # Returns the name of the macro.  For example, <tt>composed_of :balance, :class_name => 'Money'</tt> will return
-      # <tt>:balance</tt> or for <tt>has_many :clients</tt> it will return <tt>:clients</tt>.
+      # Returns the name of the macro.  For example, <tt>composed_of :balance, 
+      # :class_name => 'Money'</tt> will return <tt>:balance</tt> or for 
+      # <tt>has_many :clients</tt> it will return <tt>:clients</tt>.
       def name
         @name
       end
 
-      # Returns the macro type. For example, <tt>composed_of :balance, :class_name => 'Money'</tt> will return <tt>:composed_of</tt>
+      # Returns the macro type. For example, 
+      # <tt>composed_of :balance, :class_name => 'Money'</tt> will return <tt>:composed_of</tt>
       # or for <tt>has_many :clients</tt> will return <tt>:has_many</tt>.
       def macro
         @macro
@@ -132,11 +142,13 @@ module ActiveRecord
     end
 
 
-    # Holds all the meta-data about an aggregation as it was specified in the Active Record class.
+    # Holds all the meta-data about an aggregation as it was specified in the 
+    # Active Record class.
     class AggregateReflection < MacroReflection #:nodoc:
     end
 
-    # Holds all the meta-data about an association as it was specified in the Active Record class.
+    # Holds all the meta-data about an association as it was specified in the 
+    # Active Record class.
     class AssociationReflection < MacroReflection #:nodoc:
       # Returns the target association's class:
       #
@@ -165,14 +177,14 @@ module ActiveRecord
         klass.new(*options)
       end
 
-      # Creates a new instance of the associated class, and immediates saves it
+      # Creates a new instance of the associated class, and immediately saves it
       # with ActiveRecord::Base#save. +options+ will be passed to the class's
       # creation method. Returns the newly created object.
       def create_association(*options)
         klass.create(*options)
       end
 
-      # Creates a new instance of the associated class, and immediates saves it
+      # Creates a new instance of the associated class, and immediately saves it
       # with ActiveRecord::Base#save!. +options+ will be passed to the class's
       # creation method. If the created record doesn't pass validations, then an
       # exception will be raised.
@@ -267,10 +279,10 @@ module ActiveRecord
       # Returns whether or not the association should be validated as part of
       # the parent's validation.
       #
-      # Unless you explicitely disable validation with
+      # Unless you explicitly disable validation with
       # <tt>:validate => false</tt>, it will take place when:
       #
-      # * you explicitely enable validation; <tt>:validate => true</tt>
+      # * you explicitly enable validation; <tt>:validate => true</tt>
       # * you use autosave; <tt>:autosave => true</tt>
       # * the association is a +has_many+ association
       def validate?
@@ -306,9 +318,12 @@ module ActiveRecord
         end
     end
 
-    # Holds all the meta-data about a :through association as it was specified in the Active Record class.
+    # Holds all the meta-data about a :through association as it was specified
+    # in the Active Record class.
     class ThroughReflection < AssociationReflection #:nodoc:
-      # Gets the source of the through reflection.  It checks both a singularized and pluralized form for <tt>:belongs_to</tt> or <tt>:has_many</tt>.
+      # Gets the source of the through reflection.  It checks both a singularized
+      # and pluralized form for <tt>:belongs_to</tt> or <tt>:has_many</tt>.
+      #
       # (The <tt>:tags</tt> association on Tagging below.)
       #
       #   class Post < ActiveRecord::Base
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index 99c914d7fc..bc708b573f 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -1,6 +1,7 @@
 require 'active_support/core_ext/object/blank'
 
 module ActiveRecord
+  # = Active Record Relation
   class Relation
     JoinOperation = Struct.new(:relation, :join_class, :on)
     ASSOCIATION_METHODS = [:includes, :eager_load, :preload]
@@ -9,13 +10,13 @@ module ActiveRecord
 
     include FinderMethods, Calculations, SpawnMethods, QueryMethods, Batches
 
-    delegate :length, :collect, :map, :each, :all?, :include?, :to => :to_a
+    delegate :to_xml, :to_json, :to_yaml, :length, :collect, :map, :each, :all?, :include?, :to => :to_a
     delegate :insert, :to => :arel
 
     attr_reader :table, :klass
     attr_accessor :extensions
 
-    def initialize(klass, table, &block)
+    def initialize(klass, table)
       @klass, @table = klass, table
 
       @implicit_readonly = nil
@@ -24,12 +25,10 @@ module ActiveRecord
       SINGLE_VALUE_METHODS.each {|v| instance_variable_set(:"@#{v}_value", nil)}
       (ASSOCIATION_METHODS + MULTI_VALUE_METHODS).each {|v| instance_variable_set(:"@#{v}_values", [])}
       @extensions = []
-
-      apply_modules(Module.new(&block)) if block_given?
     end
 
     def new(*args, &block)
-      with_create_scope { @klass.new(*args, &block) }
+      scoping { @klass.new(*args, &block) }
     end
 
     def initialize_copy(other)
@@ -39,11 +38,11 @@ module ActiveRecord
     alias build new
 
     def create(*args, &block)
-      with_create_scope { @klass.create(*args, &block) }
+      scoping { @klass.create(*args, &block) }
     end
 
     def create!(*args, &block)
-      with_create_scope { @klass.create!(*args, &block) }
+      scoping { @klass.create!(*args, &block) }
     end
 
     def respond_to?(method, include_private = false)
@@ -67,7 +66,7 @@ module ActiveRecord
       preload +=  @includes_values unless eager_loading?
       preload.each {|associations| @klass.send(:preload_associations, @records, associations) }
 
-      # @readonly_value is true only if set explicity. @implicit_readonly is true if there are JOINS and no explicit SELECT.
+      # @readonly_value is true only if set explicitly. @implicit_readonly is true if there are JOINS and no explicit SELECT.
       readonly = @readonly_value.nil? ? @implicit_readonly : @readonly_value
       @records.each { |record| record.readonly! } if readonly
 
@@ -75,10 +74,12 @@ module ActiveRecord
       @records
     end
 
+    # Returns size of the records.
     def size
       loaded? ? @records.length : count
     end
 
+    # Returns true if there are no records.
     def empty?
       loaded? ? @records.empty? : count.zero?
     end
@@ -99,6 +100,25 @@ module ActiveRecord
       end
     end
 
+    # Scope all queries to the current scope.
+    #
+    # ==== Example
+    #
+    #   Comment.where(:post_id => 1).scoping do
+    #     Comment.first #=> SELECT * FROM comments WHERE post_id = 1
+    #   end
+    #
+    # Please check unscoped if you want to remove all previous scopes (including
+    # the default_scope) during the execution of a block.
+    def scoping
+      @klass.scoped_methods << self
+      begin
+        yield
+      ensure
+        @klass.scoped_methods.pop
+      end
+    end
+
     # Updates all records with details given if they match a set of conditions supplied, limits and order can
     # also be supplied. This method constructs a single SQL UPDATE statement and sends it straight to the
     # database. It does not instantiate the involved models and it does not trigger Active Record callbacks
@@ -240,8 +260,9 @@ module ActiveRecord
     #   Post.delete_all("person_id = 5 AND (category = 'Something' OR category = 'Else')")
     #   Post.delete_all(["person_id = ? AND (category = ? OR category = ?)", 5, 'Something', 'Else'])
     #
-    # Both calls delete the affected posts all at once with a single DELETE statement. If you need to destroy dependent
-    # associations or call your <tt>before_*</tt> or +after_destroy+ callbacks, use the +destroy_all+ method instead.
+    # Both calls delete the affected posts all at once with a single DELETE statement. 
+    # If you need to destroy dependent associations or call your <tt>before_*</tt> or 
+    # +after_destroy+ callbacks, use the +destroy_all+ method instead.
     def delete_all(conditions = nil)
       conditions ? where(conditions).delete_all : arel.delete.tap { reset }
     end
@@ -301,7 +322,6 @@ module ActiveRecord
           if where.is_a?(Arel::Predicates::Equality)
             hash[where.operand1.name] = where.operand2.respond_to?(:value) ? where.operand2.value : where.operand2
           end
-
           hash
         end
       end
@@ -332,7 +352,7 @@ module ActiveRecord
       elsif @klass.scopes[method]
         merge(@klass.send(method, *args, &block))
       elsif @klass.respond_to?(method)
-        @klass.send(:with_scope, self) { @klass.send(method, *args, &block) }
+        scoping { @klass.send(method, *args, &block) }
       elsif arel.respond_to?(method)
         arel.send(method, *args, &block)
       elsif match = DynamicFinderMatch.match(method)
@@ -351,10 +371,6 @@ module ActiveRecord
 
     private
 
-    def with_create_scope
-      @klass.send(:with_scope, :create => scope_for_create, :find => {}) { yield }
-    end
-
     def references_eager_loaded_tables?
       # always convert table names to downcase as in Oracle quoted table names are in uppercase
       joined_tables = (tables_in_string(arel.joins(arel)) + [table.name, table.table_alias]).compact.map(&:downcase).uniq
diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb
index 7a0c9dc612..f39951e16c 100644
--- a/activerecord/lib/active_record/relation/finder_methods.rb
+++ b/activerecord/lib/active_record/relation/finder_methods.rb
@@ -87,8 +87,8 @@ module ActiveRecord
     #     person.visits += 1
     #     person.save!
     #   end
-    def find(*args, &block)
-      return to_a.find(&block) if block_given?
+    def find(*args)
+      return to_a.find { |*block_args| yield(*block_args) } if block_given?
 
       options = args.extract_options!
 
@@ -259,8 +259,8 @@ module ActiveRecord
       record
     end
 
-    def find_with_ids(*ids, &block)
-      return to_a.find(&block) if block_given?
+    def find_with_ids(*ids)
+      return to_a.find { |*block_args| yield(*block_args) } if block_given?
 
       expects_array = ids.first.kind_of?(Array)
       return ids.first if expects_array && ids.first.empty?
diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb
index d0efa2189d..5cea2328e8 100644
--- a/activerecord/lib/active_record/relation/predicate_builder.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder.rb
@@ -20,15 +20,13 @@ module ActiveRecord
             table = Arel::Table.new(table_name, :engine => @engine)
           end
 
-          unless attribute = table[column]
-            raise StatementInvalid, "No attribute named `#{column}` exists for table `#{table.name}`"
-          end
+          attribute = table[column] || Arel::Attribute.new(table, column)
 
           case value
           when Array, ActiveRecord::Associations::AssociationCollection, ActiveRecord::Relation
             values = value.to_a
             attribute.in(values)
-          when Range
+          when Range, Arel::Relation
             attribute.in(value)
           else
             attribute.eq(value)
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index 7a48a6596a..4692271266 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -5,79 +5,92 @@ module ActiveRecord
   module QueryMethods
     extend ActiveSupport::Concern
 
-    included do
-      (ActiveRecord::Relation::ASSOCIATION_METHODS + ActiveRecord::Relation::MULTI_VALUE_METHODS).each do |query_method|
-        attr_accessor :"#{query_method}_values"
-
-        next if [:where, :having, :select].include?(query_method)
-        class_eval <<-CEVAL, __FILE__, __LINE__ + 1
-          def #{query_method}(*args, &block)
-            new_relation = clone
-            new_relation.send(:apply_modules, Module.new(&block)) if block_given?
-            value = Array.wrap(args.flatten).reject {|x| x.blank? }
-            new_relation.#{query_method}_values += value if value.present?
-            new_relation
-          end
-        CEVAL
-      end
+    attr_accessor :includes_values, :eager_load_values, :preload_values,
+                  :select_values, :group_values, :order_values, :joins_values, :where_values, :having_values,
+                  :limit_value, :offset_value, :lock_value, :readonly_value, :create_with_value, :from_value
 
-      class_eval <<-CEVAL, __FILE__, __LINE__ + 1
-        def select(*args, &block)
-          if block_given?
-            to_a.select(&block)
-          else
-            new_relation = clone
-            value = Array.wrap(args.flatten).reject {|x| x.blank? }
-            new_relation.select_values += value if value.present?
-            new_relation
-          end
-        end
-      CEVAL
-
-      [:where, :having].each do |query_method|
-        class_eval <<-CEVAL, __FILE__, __LINE__ + 1
-          def #{query_method}(*args, &block)
-            new_relation = clone
-            new_relation.send(:apply_modules, Module.new(&block)) if block_given?
-            value = build_where(*args)
-            new_relation.#{query_method}_values += Array.wrap(value) if value.present?
-            new_relation
-          end
-        CEVAL
-      end
+    def includes(*args)
+      args.reject! { |a| a.blank? }
+      clone.tap { |r| r.includes_values += args if args.present? }
+    end
+
+    def eager_load(*args)
+      clone.tap { |r| r.eager_load_values += args if args.present? }
+    end
 
-      ActiveRecord::Relation::SINGLE_VALUE_METHODS.each do |query_method|
-        attr_accessor :"#{query_method}_value"
+    def preload(*args)
+      clone.tap { |r| r.preload_values += args if args.present? }
+    end
 
-        class_eval <<-CEVAL, __FILE__, __LINE__ + 1
-          def #{query_method}(value = true, &block)
-            new_relation = clone
-            new_relation.send(:apply_modules, Module.new(&block)) if block_given?
-            new_relation.#{query_method}_value = value
-            new_relation
-          end
-        CEVAL
+    def select(*args)
+      if block_given?
+        to_a.select { |*block_args| yield(*block_args) }
+      else
+        clone.tap { |r| r.select_values += args if args.present? }
       end
     end
 
-    def extending(*modules)
-      new_relation = clone
-      new_relation.send :apply_modules, *modules
-      new_relation
+    def group(*args)
+      clone.tap { |r| r.group_values += args if args.present? }
     end
 
-    def lock(locks = true, &block)
-      relation = clone
-      relation.send(:apply_modules, Module.new(&block)) if block_given?
+    def order(*args)
+      clone.tap { |r| r.order_values += args if args.present? }
+    end
+
+    def reorder(*args)
+      clone.tap { |r| r.order_values = args if args.present? }
+    end
 
+    def joins(*args)
+      args.flatten!
+      clone.tap { |r| r.joins_values += args if args.present? }
+    end
+
+    def where(*args)
+      value = build_where(*args)
+      clone.tap { |r| r.where_values += Array.wrap(value) if value.present? }
+    end
+
+    def having(*args)
+      value = build_where(*args)
+      clone.tap { |r| r.having_values += Array.wrap(value) if value.present? }
+    end
+
+    def limit(value = true)
+      clone.tap { |r| r.limit_value = value }
+    end
+
+    def offset(value = true)
+      clone.tap { |r| r.offset_value = value }
+    end
+
+    def lock(locks = true)
       case locks
       when String, TrueClass, NilClass
-        clone.tap {|new_relation| new_relation.lock_value = locks || true }
+        clone.tap { |r| r.lock_value = locks || true }
       else
-        clone.tap {|new_relation| new_relation.lock_value = false }
+        clone.tap { |r| r.lock_value = false }
       end
     end
 
+    def readonly(value = true)
+      clone.tap { |r| r.readonly_value = value }
+    end
+
+    def create_with(value = true)
+      clone.tap { |r| r.create_with_value = value }
+    end
+
+    def from(value = true)
+      clone.tap { |r| r.from_value = value }
+    end
+
+    def extending(*modules, &block)
+      modules << Module.new(&block) if block_given?
+      clone.tap { |r| r.send(:apply_modules, *modules) }
+    end
+
     def reverse_order
       order_clause = arel.send(:order_clauses).join(', ')
       relation = except(:order)
@@ -116,45 +129,7 @@ module ActiveRecord
     def build_arel
       arel = table
 
-      joined_associations = []
-      association_joins = []
-
-      joins = @joins_values.map {|j| j.respond_to?(:strip) ? j.strip : j}.uniq
-
-      joins.each do |join|
-        association_joins << join if [Hash, Array, Symbol].include?(join.class) && !array_of_strings?(join)
-      end
-
-      stashed_association_joins = joins.select {|j| j.is_a?(ActiveRecord::Associations::ClassMethods::JoinDependency::JoinAssociation)}
-
-      non_association_joins = (joins - association_joins - stashed_association_joins).reject {|j| j.blank?}
-      custom_joins = custom_join_sql(*non_association_joins)
-
-      join_dependency = ActiveRecord::Associations::ClassMethods::JoinDependency.new(@klass, association_joins, custom_joins)
-
-      join_dependency.graft(*stashed_association_joins)
-
-      @implicit_readonly = true unless association_joins.empty? && stashed_association_joins.empty?
-
-      to_join = []
-
-      join_dependency.join_associations.each do |association|
-        if (association_relation = association.relation).is_a?(Array)
-          to_join << [association_relation.first, association.join_class, association.association_join.first]
-          to_join << [association_relation.last, association.join_class, association.association_join.last]
-        else
-          to_join << [association_relation, association.join_class, association.association_join]
-        end
-      end
-
-      to_join.each do |tj|
-        unless joined_associations.detect {|ja| ja[0] == tj[0] && ja[1] == tj[1] && ja[2] == tj[2] }
-          joined_associations << tj
-          arel = arel.join(tj[0], tj[1]).on(*tj[2])
-        end
-      end
-
-      arel = arel.join(custom_joins)
+      arel = build_joins(arel, @joins_values) if @joins_values.present?
 
       @where_values.uniq.each do |where|
         next if where.blank?
@@ -168,31 +143,18 @@ module ActiveRecord
         end
       end
 
-      @having_values.uniq.each do |h|
-        arel = h.is_a?(String) ? arel.having(h) : arel.having(*h)
-      end
+      arel = arel.having(*@having_values.uniq.select{|h| h.present?}) if @having_values.present?
 
       arel = arel.take(@limit_value) if @limit_value.present?
       arel = arel.skip(@offset_value) if @offset_value.present?
 
-      arel = arel.group(*@group_values.uniq.select{|g| g.present?})
-
-      arel = arel.order(*@order_values.uniq.select{|o| o.present?}.map(&:to_s))
+      arel = arel.group(*@group_values.uniq.select{|g| g.present?}) if @group_values.present?
 
-      selects = @select_values.uniq
+      arel = arel.order(*@order_values.uniq.select{|o| o.present?}) if @order_values.present?
 
-      quoted_table_name = @klass.quoted_table_name
-
-      if selects.present?
-        selects.each do |s|
-          @implicit_readonly = false
-          arel = arel.project(s) if s.present?
-        end
-      else
-        arel = arel.project(quoted_table_name + '.*')
-      end
+      arel = build_select(arel, @select_values.uniq)
 
-      arel = @from_value.present? ? arel.from(@from_value) : arel.from(quoted_table_name)
+      arel = arel.from(@from_value) if @from_value.present?
 
       case @lock_value
       when TrueClass
@@ -221,6 +183,63 @@ module ActiveRecord
 
     private
 
+    def build_joins(relation, joins)
+      joined_associations = []
+      association_joins = []
+
+      joins = @joins_values.map {|j| j.respond_to?(:strip) ? j.strip : j}.uniq
+
+      joins.each do |join|
+        association_joins << join if [Hash, Array, Symbol].include?(join.class) && !array_of_strings?(join)
+      end
+
+      stashed_association_joins = joins.select {|j| j.is_a?(ActiveRecord::Associations::ClassMethods::JoinDependency::JoinAssociation)}
+
+      non_association_joins = (joins - association_joins - stashed_association_joins)
+      custom_joins = custom_join_sql(*non_association_joins)
+
+      join_dependency = ActiveRecord::Associations::ClassMethods::JoinDependency.new(@klass, association_joins, custom_joins)
+
+      join_dependency.graft(*stashed_association_joins)
+
+      @implicit_readonly = true unless association_joins.empty? && stashed_association_joins.empty?
+
+      to_join = []
+
+      join_dependency.join_associations.each do |association|
+        if (association_relation = association.relation).is_a?(Array)
+          to_join << [association_relation.first, association.join_class, association.association_join.first]
+          to_join << [association_relation.last, association.join_class, association.association_join.last]
+        else
+          to_join << [association_relation, association.join_class, association.association_join]
+        end
+      end
+
+      to_join.each do |tj|
+        unless joined_associations.detect {|ja| ja[0] == tj[0] && ja[1] == tj[1] && ja[2] == tj[2] }
+          joined_associations << tj
+          relation = relation.join(tj[0], tj[1]).on(*tj[2])
+        end
+      end
+
+      relation.join(custom_joins)
+    end
+
+    def build_select(arel, selects)
+      if selects.present?
+        @implicit_readonly = false
+        # TODO: fix this ugly hack, we should refactor the callers to get an ARel compatible array.
+        # Before this change we were passing to ARel the last element only, and ARel is capable of handling an array
+        if selects.all? { |s| s.is_a?(String) || !s.is_a?(Arel::Expression) } && !(selects.last =~ /^COUNT\(/)
+          arel.project(*selects)
+        else
+          arel.project(selects.last)
+        end
+      else
+        arel.project(@klass.quoted_table_name + '.*')
+      end
+    end
+
     def apply_modules(modules)
       values = Array.wrap(modules)
       @extensions += values if values.present?
diff --git a/activerecord/lib/active_record/relation/spawn_methods.rb b/activerecord/lib/active_record/relation/spawn_methods.rb
index bb1f138f5b..7712ad2569 100644
--- a/activerecord/lib/active_record/relation/spawn_methods.rb
+++ b/activerecord/lib/active_record/relation/spawn_methods.rb
@@ -6,7 +6,7 @@ module ActiveRecord
       merged_relation = clone
       return merged_relation unless r
 
-      (Relation::ASSOCIATION_METHODS + Relation::MULTI_VALUE_METHODS).reject {|m| [:joins, :where].include?(m)}.each do |method|
+      ((Relation::ASSOCIATION_METHODS + Relation::MULTI_VALUE_METHODS) - [:joins, :where]).each do |method|
         value = r.send(:"#{method}_values")
         merged_relation.send(:"#{method}_values=", value) if value.present?
       end
diff --git a/activerecord/lib/active_record/schema.rb b/activerecord/lib/active_record/schema.rb
index a833356d15..e2783087ec 100644
--- a/activerecord/lib/active_record/schema.rb
+++ b/activerecord/lib/active_record/schema.rb
@@ -1,6 +1,8 @@
 require 'active_support/core_ext/object/blank'
 
 module ActiveRecord
+  # = Active Record Schema
+  # 
   # Allows programmers to programmatically define a schema in a portable
   # DSL. This means you can define tables, indexes, etc. without using SQL
   # directly, so your applications can more easily support multiple
diff --git a/activerecord/lib/active_record/schema_dumper.rb b/activerecord/lib/active_record/schema_dumper.rb
index cd54653581..a4757773d8 100644
--- a/activerecord/lib/active_record/schema_dumper.rb
+++ b/activerecord/lib/active_record/schema_dumper.rb
@@ -2,6 +2,8 @@ require 'stringio'
 require 'active_support/core_ext/big_decimal'
 
 module ActiveRecord
+  # = Active Record Schema Dumper
+  #
   # This class is used to dump the database schema for some connection to some
   # output format (i.e., ActiveRecord::Schema).
   class SchemaDumper #:nodoc:
@@ -39,13 +41,14 @@ module ActiveRecord
         define_params = @version ? ":version => #{@version}" : ""
 
         stream.puts <<HEADER
-# This file is auto-generated from the current state of the database. Instead of editing this file, 
-# please use the migrations feature of Active Record to incrementally modify your database, and
-# then regenerate this schema definition.
+# This file is auto-generated from the current state of the database. Instead 
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
 #
-# Note that this schema.rb definition is the authoritative source for your database schema. If you need
-# to create the application database on another system, you should be using db:schema:load, not running
-# all the migrations from scratch. The latter is a flawed and unsustainable approach (the more migrations
+# Note that this schema.rb definition is the authoritative source for your 
+# database schema. If you need to create the application database on another
+# system, you should be using db:schema:load, not running all the migrations
+# from scratch. The latter is a flawed and unsustainable approach (the more migrations
 # you'll amass, the slower it'll run and the greater likelihood for issues).
 #
 # It's strongly recommended to check this file into your version control system.
@@ -173,15 +176,15 @@ HEADER
       def indexes(table, stream)
         if (indexes = @connection.indexes(table)).any?
           add_index_statements = indexes.map do |index|
-            statment_parts = [ ('add_index ' + index.table.inspect) ]
-            statment_parts << index.columns.inspect
-            statment_parts << (':name => ' + index.name.inspect)
-            statment_parts << ':unique => true' if index.unique
+            statement_parts = [ ('add_index ' + index.table.inspect) ]
+            statement_parts << index.columns.inspect
+            statement_parts << (':name => ' + index.name.inspect)
+            statement_parts << ':unique => true' if index.unique
 
             index_lengths = index.lengths.compact if index.lengths.is_a?(Array)
-            statment_parts << (':length => ' + Hash[*index.columns.zip(index.lengths).flatten].inspect) if index_lengths.present?
+            statement_parts << (':length => ' + Hash[*index.columns.zip(index.lengths).flatten].inspect) if index_lengths.present?
 
-            '  ' + statment_parts.join(', ')
+            '  ' + statement_parts.join(', ')
           end
 
           stream.puts add_index_statements.sort.join("\n")
diff --git a/activerecord/lib/active_record/serialization.rb b/activerecord/lib/active_record/serialization.rb
index b49471f7ab..2d8bd184f3 100644
--- a/activerecord/lib/active_record/serialization.rb
+++ b/activerecord/lib/active_record/serialization.rb
@@ -1,4 +1,5 @@
 module ActiveRecord #:nodoc:
+  # = Active Record Serialization
   module Serialization
     extend ActiveSupport::Concern
     include ActiveModel::Serializers::JSON
@@ -22,6 +23,7 @@ module ActiveRecord #:nodoc:
 
     private
       # Add associations specified via the <tt>:includes</tt> option.
+      # 
       # Expects a block that takes as arguments:
       #   +association+ - name of the association
       #   +records+     - the association record(s) to be serialized
diff --git a/activerecord/lib/active_record/session_store.rb b/activerecord/lib/active_record/session_store.rb
index 931872eded..b88d550086 100644
--- a/activerecord/lib/active_record/session_store.rb
+++ b/activerecord/lib/active_record/session_store.rb
@@ -1,4 +1,6 @@
 module ActiveRecord
+  # = Active Record Session Store
+  #
   # A session store backed by an Active Record class.  A default class is
   # provided, but any object duck-typing to an Active Record Session class
   # with text +session_id+ and +data+ attributes is sufficient.
@@ -7,6 +9,7 @@ module ActiveRecord
   #   +id+ (numeric primary key),
   #   +session_id+ (text, or longtext if your session data exceeds 65K), and
   #   +data+ (text or longtext; careful if your session data exceeds 65KB).
+  # 
   # The +session_id+ column should always be indexed for speedy lookups.
   # Session data is marshaled to the +data+ column in Base64 format.
   # If the data you write is larger than the column's size limit,
@@ -14,9 +17,11 @@ module ActiveRecord
   #
   # You may configure the table name, primary key, and data column.
   # For example, at the end of <tt>config/environment.rb</tt>:
+  #
   #   ActiveRecord::SessionStore::Session.table_name = 'legacy_session_table'
   #   ActiveRecord::SessionStore::Session.primary_key = 'session_id'
   #   ActiveRecord::SessionStore::Session.data_column_name = 'legacy_session_data'
+  #
   # Note that setting the primary key to the +session_id+ frees you from
   # having a separate +id+ column if you don't want it.  However, you must
   # set <tt>session.model.id = session.session_id</tt> by hand!  A before filter
@@ -29,8 +34,11 @@ module ActiveRecord
   # You may provide your own session class implementation, whether a
   # feature-packed Active Record or a bare-metal high-performance SQL
   # store, by setting
+  #
   #   ActiveRecord::SessionStore.session_class = MySessionClass
+  #
   # You must implement these methods:
+  #
   #   self.find_by_session_id(session_id)
   #   initialize(hash_of_session_id_and_data)
   #   attr_reader :session_id
@@ -310,6 +318,14 @@ module ActiveRecord
         sid
       end
       
+      def destroy(env)
+        if sid = current_session_id(env)
+          Base.silence do
+            get_session_model(env, sid).destroy
+          end
+        end
+      end
+
       def get_session_model(env, sid)
         if env[ENV_SESSION_OPTIONS_KEY][:id].nil?
           env[SESSION_RECORD_KEY] = find_session(sid)
diff --git a/activerecord/lib/active_record/test_case.rb b/activerecord/lib/active_record/test_case.rb
index 0a77ad5fd7..e61a378d17 100644
--- a/activerecord/lib/active_record/test_case.rb
+++ b/activerecord/lib/active_record/test_case.rb
@@ -1,4 +1,7 @@
 module ActiveRecord
+  # = Active Record Test Case
+  # 
+  # Defines some test assertions to test against SQL queries.
   class TestCase < ActiveSupport::TestCase #:nodoc:
     def assert_date_from_db(expected, actual, message = nil)
       # SybaseAdapter doesn't have a separate column type just for dates,
diff --git a/activerecord/lib/active_record/timestamp.rb b/activerecord/lib/active_record/timestamp.rb
index 9fba8f0aca..ffd12d2082 100644
--- a/activerecord/lib/active_record/timestamp.rb
+++ b/activerecord/lib/active_record/timestamp.rb
@@ -1,11 +1,16 @@
 module ActiveRecord
-  # Active Record automatically timestamps create and update operations if the table has fields
-  # named created_at/created_on or updated_at/updated_on.
+  # = Active Record Timestamp
+  # 
+  # Active Record automatically timestamps create and update operations if the
+  # table has fields named <tt>created_at/created_on</tt> or 
+  # <tt>updated_at/updated_on</tt>.
+  #
+  # Timestamping can be turned off by setting:
   #
-  # Timestamping can be turned off by setting
   #   <tt>ActiveRecord::Base.record_timestamps = false</tt>
   #
-  # Timestamps are in the local timezone by default but you can use UTC by setting
+  # Timestamps are in the local timezone by default but you can use UTC by setting:
+  #
   #   <tt>ActiveRecord::Base.default_timezone = :utc</tt>
   module Timestamp
     extend ActiveSupport::Concern
@@ -16,8 +21,9 @@ module ActiveRecord
     end
     
     # Saves the record with the updated_at/on attributes set to the current time.
-    # If the save fails because of validation errors, an ActiveRecord::RecordInvalid exception is raised.
-    # If an attribute name is passed, that attribute is used for the touch instead of the updated_at/on attributes.
+    # If the save fails because of validation errors, an 
+    # ActiveRecord::RecordInvalid exception is raised. If an attribute name is passed,
+    # that attribute is used for the touch instead of the updated_at/on attributes.
     #
     # Examples:
     #
diff --git a/activerecord/lib/active_record/transactions.rb b/activerecord/lib/active_record/transactions.rb
index 620758f5af..a7709b9489 100644
--- a/activerecord/lib/active_record/transactions.rb
+++ b/activerecord/lib/active_record/transactions.rb
@@ -11,7 +11,8 @@ module ActiveRecord
     included do
       define_callbacks :commit, :rollback, :terminator => "result == false", :scope => [:kind, :name]
     end
-
+    # = Active Record Transactions
+    #
     # Transactions are protective blocks where SQL statements are only permanent
     # if they can all succeed as one atomic action. The classic example is a
     # transfer between two accounts where you can only have a deposit if the
@@ -19,7 +20,8 @@ module ActiveRecord
     # the database and guard the data against program errors or database
     # break-downs. So basically you should use transaction blocks whenever you
     # have a number of statements that must be executed together or not at all.
-    # Example:
+    #
+    # For example:
     #
     #   ActiveRecord::Base.transaction do
     #     david.withdrawal(100)
@@ -320,6 +322,7 @@ module ActiveRecord
         if @_start_transaction_state[:level] < 1
           restore_state = remove_instance_variable(:@_start_transaction_state)
           if restore_state
+            @attributes = @attributes.dup if @attributes.frozen?
             @new_record = restore_state[:new_record]
             @destroyed = restore_state[:destroyed]
             if restore_state[:id]
diff --git a/activerecord/lib/active_record/validations.rb b/activerecord/lib/active_record/validations.rb
index be64e00bd1..b98fd353aa 100644
--- a/activerecord/lib/active_record/validations.rb
+++ b/activerecord/lib/active_record/validations.rb
@@ -1,6 +1,9 @@
 module ActiveRecord
+  # = Active Record Validations
+  #
   # Raised by <tt>save!</tt> and <tt>create!</tt> when the record is invalid.  Use the
   # +record+ method to retrieve the record which did not validate.
+  #
   #   begin
   #     complex_operation_that_calls_save!_internally
   #   rescue ActiveRecord::RecordInvalid => invalid
@@ -49,12 +52,12 @@ module ActiveRecord
     # Runs all the specified validations and returns true if no errors were added otherwise false.
     def valid?(context = nil)
       context ||= (new_record? ? :create : :update)
-      super(context)
+      output = super(context)
 
       deprecated_callback_method(:validate)
       deprecated_callback_method(:"validate_on_#{context}")
 
-      errors.empty?
+      errors.empty? && output
     end
 
   protected
diff --git a/activerecord/lib/active_record/validations/associated.rb b/activerecord/lib/active_record/validations/associated.rb
index e41635134c..0b0f5682aa 100644
--- a/activerecord/lib/active_record/validations/associated.rb
+++ b/activerecord/lib/active_record/validations/associated.rb
@@ -3,7 +3,7 @@ module ActiveRecord
     class AssociatedValidator < ActiveModel::EachValidator
       def validate_each(record, attribute, value)
         return if (value.is_a?(Array) ? value : [value]).collect{ |r| r.nil? || r.valid? }.all?
-        record.errors.add(attribute, :invalid, :default => options[:message], :value => value)
+        record.errors.add(attribute, :invalid, options.merge(:value => value))
       end
     end
 
diff --git a/activerecord/lib/active_record/validations/uniqueness.rb b/activerecord/lib/active_record/validations/uniqueness.rb
index 6283bdd0d6..1c9ecc7b1b 100644
--- a/activerecord/lib/active_record/validations/uniqueness.rb
+++ b/activerecord/lib/active_record/validations/uniqueness.rb
@@ -32,7 +32,7 @@ module ActiveRecord
         end
 
         if relation.exists?
-          record.errors.add(attribute, :taken, :default => options[:message], :value => value)
+          record.errors.add(attribute, :taken, options.except(:case_sensitive, :scope).merge(:value => value))
         end
       end
 
diff --git a/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb
index bbb7c53d86..8ac21c1410 100644
--- a/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb
+++ b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb
@@ -1,11 +1,17 @@
 class <%= migration_class_name %> < ActiveRecord::Migration
-  def self.up<% attributes.each do |attribute| %>
-    <%= migration_action %>_column :<%= table_name %>, :<%= attribute.name %><% if migration_action == 'add' %>, :<%= attribute.type %><% end -%>
-  <%- end %>
+  def self.up
+<% attributes.each do |attribute| -%>
+  <%- if migration_action -%>
+    <%= migration_action %>_column :<%= table_name %>, :<%= attribute.name %><% if migration_action == 'add' %>, :<%= attribute.type %><% end %>
+  <%- end -%>
+<%- end -%>
   end
 
-  def self.down<% attributes.reverse.each do |attribute| %>
-    <%= migration_action == 'add' ? 'remove' : 'add' %>_column :<%= table_name %>, :<%= attribute.name %><% if migration_action == 'remove' %>, :<%= attribute.type %><% end -%>
-  <%- end %>
+  def self.down
+<% attributes.reverse.each do |attribute| -%>
+  <%- if migration_action -%>
+    <%= migration_action == 'add' ? 'remove' : 'add' %>_column :<%= table_name %>, :<%= attribute.name %><% if migration_action == 'remove' %>, :<%= attribute.type %><% end %>
+  <%- end -%>
+<%- end -%>
   end
 end
diff --git a/activerecord/lib/rails/generators/active_record/model/model_generator.rb b/activerecord/lib/rails/generators/active_record/model/model_generator.rb
index 539c2517ee..960c29c49c 100644
--- a/activerecord/lib/rails/generators/active_record/model/model_generator.rb
+++ b/activerecord/lib/rails/generators/active_record/model/model_generator.rb
@@ -22,7 +22,7 @@ module ActiveRecord
 
       def create_module_file
         return if class_path.empty?
-        template 'module.rb', File.join('app/models', "#{class_path.join('/')}.rb")
+        template 'module.rb', File.join('app/models', "#{class_path.join('/')}.rb") if behavior == :invoke
       end
 
       hook_for :test_framework