1 files changed, 8 insertions, 4 deletions
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index 171a6f4391..a444aac23c 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -63,7 +63,7 @@ module ActiveRecord
     #   records, artists => artists_records
     #   music_artists, music_records => music_artists_records
     def self.derive_join_table_name(first_table, second_table) # :nodoc:
-      [first_table.to_s, second_table.to_s].sort.join("\0").gsub(/^(.*_)(.+)\0\1(.+)/, '\1\2_\3').gsub("\0", "_")
+      [first_table.to_s, second_table.to_s].sort.join("\0").gsub(/^(.*_)(.+)\0\1(.+)/, '\1\2_\3').tr("\0", "_")
     end
 
     module ClassMethods
@@ -247,12 +247,12 @@ module ActiveRecord
       # Returns a hash where the keys are column names and the values are
       # default values when instantiating the AR object for this table.
       def column_defaults
-        default_attributes.to_hash
+        _default_attributes.to_hash
       end
 
-      def default_attributes # :nodoc:
+      def _default_attributes # :nodoc:
         @default_attributes ||= attributes_builder.build_from_database(
-          columns_hash.transform_values(&:default))
+          raw_default_values)
       end
 
       # Returns an array of column names as strings.
@@ -331,6 +331,10 @@ module ActiveRecord
           base.table_name
         end
       end
+
+      def raw_default_values
+        columns_hash.transform_values(&:default)
+      end
     end
   end
 end