diff --git a/lib/activeuuid.rb b/lib/activeuuid.rb
index 0877a7b..1e5a940 100644
--- a/lib/activeuuid.rb
+++ b/lib/activeuuid.rb
@@ -1,6 +1,8 @@
 require "activeuuid/version"
 require 'activeuuid/patches'
+require 'activeuuid/association'
 require 'activeuuid/uuid'
+require 'activeuuid/schema_dumper'
 require 'activeuuid/railtie' if defined?(Rails::Railtie)
 
 module ActiveUUID
diff --git a/lib/activeuuid/association.rb b/lib/activeuuid/association.rb
new file mode 100644
index 0000000..87f62ef
--- /dev/null
+++ b/lib/activeuuid/association.rb
@@ -0,0 +1,45 @@
+require 'active_record'
+require 'active_record/associations/preloader/association'
+
+module ActiveRecord::Associations
+  class Preloader
+    class Association
+      def owners_by_key
+        @owners_by_key ||= owners.group_by do |owner|
+          key = owner[owner_key_name]
+          # NOTE: key.to_s screws up the literal in the `WHERE ... IN (...)` clause
+          # in AR::Base.includes... so we patch and comment it out.
+          key # && key.to_s
+        end
+      end
+
+      def associated_records_by_owner
+        owners_map = owners_by_key
+        owner_keys = owners_map.keys.compact
+
+        if klass.nil? || owner_keys.empty?
+          records = []
+        else
+          # Some databases impose a limit on the number of ids in a list (in Oracle it's 1000)
+          # Make several smaller queries if necessary or make one query if the adapter supports it
+          sliced  = owner_keys.each_slice(model.connection.in_clause_length || owner_keys.size)
+          records = sliced.map { |slice| records_for(slice) }.flatten
+        end
+
+        # Each record may have multiple owners, and vice-versa
+        records_by_owner = Hash[owners.map { |owner| [owner, []] }]
+        records.each do |record|
+          owner_key = record[association_key_name].to_s
+          # NOTE: #to_s screws up the literal in the `WHERE ... IN (...)` clause
+          # in AR::Base.includes... so we patch and comment it out.
+          owner_key = record[association_key_name] # .to_s
+
+          owners_map[owner_key].each do |owner|
+            records_by_owner[owner] << record
+          end
+        end
+        records_by_owner
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/activeuuid/patches.rb b/lib/activeuuid/patches.rb
index 5f89dc3..7c3507f 100644
--- a/lib/activeuuid/patches.rb
+++ b/lib/activeuuid/patches.rb
@@ -8,10 +8,13 @@ module Migrations
       def uuid(*column_names)
         options = column_names.extract_options!
         column_names.each do |name|
-          type = @base.adapter_name.downcase == 'postgresql' ? 'uuid' : 'binary(16)'
+          type = adapter_name.downcase == 'postgresql' ? 'uuid' : 'binary(16)'
           column(name, "#{type}#{' PRIMARY KEY' if options.delete(:primary_key)}", options)
         end
       end
+      def adapter_name
+        defined?(@base) ? @base.adapter_name : ActiveRecord::Base.connection.adapter_name
+      end
     end
 
     module Column
@@ -29,7 +32,7 @@ def type_cast_code_with_uuid(var_name)
         end
 
         def simplified_type_with_uuid(field_type)
-          return :uuid if field_type == 'binary(16)' || field_type == 'binary(16,0)'
+          return :uuid if field_type == 'binary(16)' || field_type == 'binary(16,0)' || field_type == 'tinyblob'
           simplified_type_without_uuid(field_type)
         end
 
diff --git a/lib/activeuuid/schema_dumper.rb b/lib/activeuuid/schema_dumper.rb
new file mode 100644
index 0000000..8486228
--- /dev/null
+++ b/lib/activeuuid/schema_dumper.rb
@@ -0,0 +1,119 @@
+require 'active_record/schema_dumper'
+
+class ActiveRecord::SchemaDumper
+  private
+  def default_string(value)
+    case value
+    when BigDecimal
+      value.to_s
+    when Date, DateTime, Time
+      "'" + value.to_s(:db) + "'"
+    else
+      value.inspect
+    end
+  end
+
+  def spec_for_column(column)
+    spec = {}
+    spec[:name]      = column.name.inspect
+
+    # AR has an optimization which handles zero-scale decimals as integers. This
+    # code ensures that the dumper still dumps the column as a decimal.
+    spec[:type]      = case column.type
+    when :integer
+      column.sql_type =~ /^(numeric|decimal)/ ? 'decimal' : 'integer'
+    when :string
+      column.sql_type == 'uuid' ? 'uuid' : 'string'
+    else
+      column.type.to_s
+    end
+    spec[:limit]     = column.limit.inspect if column.limit != @types[column.type][:limit] && spec[:type] != 'decimal'
+    spec[:precision] = column.precision.inspect if column.precision
+    spec[:scale]     = column.scale.inspect if column.scale
+    spec[:null]      = 'false' unless column.null
+    spec[:default]   = default_string(column.default) if column.has_default?
+    (spec.keys - [:name, :type]).each{ |k| spec[k].insert(0, "#{k.inspect} => ")}
+    spec
+  end
+
+  # Adapted from rails 3.2 code
+  def table(table, stream)
+    columns = @connection.columns(table)
+    begin
+      tbl = StringIO.new
+
+      # first dump primary key column
+      if @connection.respond_to?(:primary_key)
+        pk = @connection.primary_key(table)
+      elsif @connection.respond_to?(:pk_and_sequence_for)
+        pk, _ = @connection.pk_and_sequence_for(table)
+      end
+
+      tbl.print "  create_table #{remove_prefix_and_suffix(table).inspect}"
+      if columns.detect { |c| c.name == pk && c.type == :integer}
+        if pk != 'id'
+          tbl.print %Q(, :primary_key => "#{pk}")
+        end
+      else
+        tbl.print ", :id => false"
+      end
+      tbl.print ", :force => true"
+      tbl.puts " do |t|"
+
+      # then dump all non-primary key columns
+      column_specs = columns.map do |column|
+        raise StandardError, "Unknown type '#{column.sql_type}' for column '#{column.name}'" if @types[column.type].nil?
+        next if column.name == pk
+        spec_for_column column
+      end.compact
+
+      # explicitly prepend non-integer primary key
+      if col = columns.detect { |c| c.name == pk && c.type != :integer}
+        pk_spec = spec_for_column col
+        pk_spec.delete(:null)
+        pk_spec[:primary_key] = ":primary_key => true"
+        column_specs.unshift pk_spec
+      end
+
+      # find all migration keys used in this table
+      keys = [:name, :limit, :precision, :scale, :default, :null, :primary_key] & column_specs.map{ |k| k.keys }.flatten
+
+      # figure out the lengths for each column based on above keys
+      lengths = keys.map{ |key| column_specs.map{ |spec| spec[key] ? spec[key].length + 2 : 0 }.max }
+
+      # the string we're going to sprintf our values against, with standardized column widths
+      format_string = lengths.map{ |len| "%-#{len}s" }
+
+      # find the max length for the 'type' column, which is special
+      type_length = column_specs.map{ |column| column[:type].length }.max
+
+      # add column type definition to our format string
+      format_string.unshift "    t.%-#{type_length}s "
+
+      format_string *= ''
+
+      column_specs.each do |colspec|
+        values = keys.zip(lengths).map{ |key, len| colspec.key?(key) ? colspec[key] + ", " : " " * len }
+        values.unshift colspec[:type]
+        tbl.print((format_string % values).gsub(/,\s*$/, ''))
+        tbl.puts
+      end
+
+      tbl.puts "  end"
+      tbl.puts
+
+      indexes(table, tbl)
+
+      tbl.rewind
+      stream.print tbl.read
+    rescue => e
+      stream.puts "# Could not dump table #{table.inspect} because of following #{e.class}"
+      stream.puts "#   #{e.message}"
+      stream.puts
+      puts e
+      puts e.backtrace
+    end
+
+    stream
+  end
+end
\ No newline at end of file
diff --git a/lib/activeuuid/uuid.rb b/lib/activeuuid/uuid.rb
index dcff691..472ca11 100644
--- a/lib/activeuuid/uuid.rb
+++ b/lib/activeuuid/uuid.rb
@@ -18,7 +18,7 @@ def quoted_id
     end
 
     def as_json(options = nil)
-      hexdigest.upcase
+      hexdigest ? hexdigest.upcase : to_s
     end
 
     def to_param
@@ -54,25 +54,25 @@ def self.parse_string(str)
 module Arel
   module Visitors
     class DepthFirst < Arel::Visitors::Visitor
-      def visit_UUIDTools_UUID(o)
+      def visit_UUIDTools_UUID(o, a)
         o.quoted_id
       end
     end
 
     class MySQL < Arel::Visitors::ToSql
-      def visit_UUIDTools_UUID(o)
+      def visit_UUIDTools_UUID(o, a)
         o.quoted_id
       end
     end
 
     class SQLite < Arel::Visitors::ToSql
-      def visit_UUIDTools_UUID(o)
+      def visit_UUIDTools_UUID(o, a)
         o.quoted_id
       end
     end
 
     class PostgreSQL < Arel::Visitors::ToSql
-      def visit_UUIDTools_UUID(o)
+      def visit_UUIDTools_UUID(o, a)
         "'#{o.to_s}'"
       end
     end
@@ -90,7 +90,7 @@ module UUID
       self._uuid_generator = :random
 
       singleton_class.alias_method_chain :instantiate, :uuid
-      before_create :generate_uuids_if_needed
+      after_initialize :generate_uuids_if_needed
     end
 
     module ClassMethods
@@ -114,7 +114,7 @@ def uuids(*attributes)
         EOS
       end
 
-      def instantiate_with_uuid(record)
+      def instantiate_with_uuid(record, column_types={})
         uuid_columns.each do |uuid_column|
           record[uuid_column] = UUIDTools::UUID.serialize(record[uuid_column]).to_s if record[uuid_column]
         end
@@ -143,7 +143,7 @@ def create_uuid
 
     def generate_uuids_if_needed
       primary_key = self.class.primary_key
-      if self.class.columns_hash[primary_key].type == :uuid
+      if primary_key && self.class.columns_hash[primary_key].type == :uuid
         send("#{primary_key}=", create_uuid) unless send("#{primary_key}?")
       end
     end
diff --git a/spec/fabricators/tag_fabricator.rb b/spec/fabricators/tag_fabricator.rb
new file mode 100644
index 0000000..134a88b
--- /dev/null
+++ b/spec/fabricators/tag_fabricator.rb
@@ -0,0 +1,3 @@
+Fabricator(:tag) do
+  name { Forgery::LoremIpsum.word }
+end
\ No newline at end of file
diff --git a/spec/fabricators/uuid_article_fabricator.rb b/spec/fabricators/uuid_article_fabricator.rb
index 71acb18..23f65bf 100644
--- a/spec/fabricators/uuid_article_fabricator.rb
+++ b/spec/fabricators/uuid_article_fabricator.rb
@@ -1,4 +1,5 @@
 Fabricator(:uuid_article) do
   title { Forgery::LoremIpsum.word }
   body { Forgery::LoremIpsum.sentence }
+  tags(count: 5)
 end
diff --git a/spec/lib/activerecord_spec.rb b/spec/lib/activerecord_spec.rb
index 69b6f7e..7b06c76 100644
--- a/spec/lib/activerecord_spec.rb
+++ b/spec/lib/activerecord_spec.rb
@@ -43,7 +43,7 @@
         spec_for_adapter do |adapters|
           adapters.sqlite3 { connection.change_column table_name, column_name, :uuid }
           adapters.mysql2 { connection.change_column table_name, column_name, :uuid }
-          # adapters.postgresql { connection.change_column table_name, column_name, :uuid }
+          adapters.postgresql { connection.change_column table_name, column_name, :uuid }
         end
       end
 
@@ -130,6 +130,11 @@
     specify { model.where(id: id.raw).first.should == article }
   end
 
+  context '.includes' do
+     specify { model.includes(:tags).first.tags.count.should == 5 }
+     specify { model.includes(:tags).first.tags.first.uuid_article.should == article }
+  end
+
   context '#destroy' do
     subject { article }
     its(:delete) { should be_true }
diff --git a/spec/lib/schema_dumper_spec.rb b/spec/lib/schema_dumper_spec.rb
new file mode 100644
index 0000000..89011c5
--- /dev/null
+++ b/spec/lib/schema_dumper_spec.rb
@@ -0,0 +1,40 @@
+require 'spec_helper'
+
+describe ActiveRecord::SchemaDumper do
+  let!(:connection) { ActiveRecord::Base.connection }
+  let(:table_name) { :test_uuid_pk_dump }
+
+  before do
+    connection.drop_table(table_name) if connection.table_exists?(table_name)
+    connection.create_table table_name, :id => false do |t|
+      t.uuid :id, :primary_key => true
+    end
+  end
+
+  after do
+    connection.drop_table table_name
+  end
+
+  context 'dump' do
+    let(:dump) do
+      stream = StringIO.new
+      ActiveRecord::SchemaDumper::dump(connection, stream)
+      stream.string.split("\n")
+    end
+    it 'should generate a dump' do
+      dump.should be_a_kind_of(Array)
+    end
+    context 'schema definition' do
+      let(:create_table_line) { dump.index{|l| /create_table "#{table_name}", :id =\> false/ =~ l} }
+      it 'should have a table creation statement' do
+        create_table_line.should be_a_kind_of(Numeric)
+      end
+      context 'table' do
+        it 'should have a uuid primary key' do
+          create_table_line.should_not be_nil
+          dump[create_table_line+1].should match(/t.uuid *"id", *:primary_key =\> true/)
+        end
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/spec/support/migrate/20130808112105_create_tags.rb b/spec/support/migrate/20130808112105_create_tags.rb
new file mode 100644
index 0000000..d4974ca
--- /dev/null
+++ b/spec/support/migrate/20130808112105_create_tags.rb
@@ -0,0 +1,10 @@
+class CreateTags < ActiveRecord::Migration
+  def change
+    create_table :tags, :id => false do |t|
+      t.uuid :id, :primary_key => true
+      t.string :name
+      t.uuid :uuid_article_id
+      t.timestamps
+    end
+  end
+end
\ No newline at end of file
diff --git a/spec/support/models/tag.rb b/spec/support/models/tag.rb
new file mode 100644
index 0000000..bef1335
--- /dev/null
+++ b/spec/support/models/tag.rb
@@ -0,0 +1,4 @@
+class Tag < ActiveRecord::Base
+  include ActiveUUID::UUID
+  belongs_to :uuid_article
+end
\ No newline at end of file
diff --git a/spec/support/models/uuid_article.rb b/spec/support/models/uuid_article.rb
index 0292bb9..10a159d 100644
--- a/spec/support/models/uuid_article.rb
+++ b/spec/support/models/uuid_article.rb
@@ -1,3 +1,5 @@
 class UuidArticle < ActiveRecord::Base
   include ActiveUUID::UUID
+
+  has_many :tags
 end