column types are passed from the result set to the instantiated AR object

4 files changed, 20 insertions, 5 deletions

diff --git a/activerecord/lib/active_record/core.rb b/activerecord/lib/active_record/core.rb
index 93b8e269fb..74403f9e35 100644
--- a/activerecord/lib/active_record/core.rb
+++ b/activerecord/lib/active_record/core.rb
@@ -165,6 +165,7 @@ module ActiveRecord
     #   User.new({ :first_name => 'Jamie', :is_admin => true }, :without_protection => true)
     def initialize(attributes = nil, options = {})
       @attributes = self.class.initialize_attributes(self.class.column_defaults.dup)
+      @columns_hash = self.class.columns_hash.dup
 
       init_internals
 
@@ -190,6 +191,8 @@ module ActiveRecord
     #   post.title # => 'hello world'
     def init_with(coder)
       @attributes = self.class.initialize_attributes(coder['attributes'])
+      @columns_hash = self.class.columns_hash.merge(coder['column_types'] || {})
+
 
       init_internals
 
@@ -341,8 +344,6 @@ module ActiveRecord
 
       @attributes[pk] = nil unless @attributes.key?(pk)
 
-      @columns_hash = self.class.columns_hash.dup
-
       @relation               = nil
       @aggregation_cache      = {}
       @association_cache      = {}
diff --git a/activerecord/lib/active_record/inheritance.rb b/activerecord/lib/active_record/inheritance.rb
index eaa7deac5a..1f5b3b2e79 100644
--- a/activerecord/lib/active_record/inheritance.rb
+++ b/activerecord/lib/active_record/inheritance.rb
@@ -62,7 +62,7 @@ module ActiveRecord
       # Finder methods must instantiate through this method to work with the
       # single-table inheritance model that makes it possible to create
       # objects of different types from the same table.
-      def instantiate(record)
+      def instantiate(record, column_types = {})
         sti_class = find_sti_class(record[inheritance_column])
         record_id = sti_class.primary_key && record[sti_class.primary_key]
 
@@ -77,7 +77,8 @@ module ActiveRecord
             IdentityMap.add(instance)
           end
         else
-          instance = sti_class.allocate.init_with('attributes' => record)
+          instance = sti_class.allocate.init_with('attributes' => record,
+                                                  'column_types' => column_types)
         end
 
         instance
diff --git a/activerecord/lib/active_record/querying.rb b/activerecord/lib/active_record/querying.rb
index 5945b05190..0e6fecbc4b 100644
--- a/activerecord/lib/active_record/querying.rb
+++ b/activerecord/lib/active_record/querying.rb
@@ -1,4 +1,5 @@
 require 'active_support/core_ext/module/delegation'
+require 'active_support/deprecation'
 
 module ActiveRecord
   module Querying
@@ -36,7 +37,15 @@ module ActiveRecord
     def find_by_sql(sql, binds = [])
       logging_query_plan do
         result_set = connection.select_all(sanitize_sql(sql), "#{name} Load", binds)
-        result_set.map { |record| instantiate(record) }
+        column_types = {}
+
+        if result_set.respond_to? :column_types
+          column_types = result_set.column_types
+        else
+          ActiveSupport::Deprecation.warn "the object returned from `select_all` must respond to `column_types`"
+        end
+
+        result_set.map { |record| instantiate(record, column_types) }
       end
     end
 
diff --git a/activerecord/lib/active_record/result.rb b/activerecord/lib/active_record/result.rb
index 60a2e90e23..4eb2cf3a72 100644
--- a/activerecord/lib/active_record/result.rb
+++ b/activerecord/lib/active_record/result.rb
@@ -49,6 +49,10 @@ module ActiveRecord
       @hash_rows = nil
     end
 
+    def column_types
+      {}
+    end
+
     private
     def hash_rows
       @hash_rows ||= @rows.map { |row|