1 files changed, 6 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index a0d9086875..582dd360f0 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -14,10 +14,7 @@ module ActiveRecord
   module ConnectionAdapters # :nodoc:
     extend ActiveSupport::Autoload
 
-    autoload_at 'active_record/connection_adapters/column' do
-      autoload :Column
-      autoload :NullColumn
-    end
+    autoload :Column
     autoload :ConnectionSpecification
 
     autoload_at 'active_record/connection_adapters/abstract/schema_definitions' do
@@ -267,7 +264,7 @@ module ActiveRecord
 
       # Returns a bind substitution value given a bind +index+ and +column+
       # NOTE: The column param is currently being used by the sqlserver-adapter
-      def substitute_at(column, index)
+      def substitute_at(column, index = 0)
         Arel::Nodes::BindParam.new '?'
       end
 
@@ -386,6 +383,10 @@ module ActiveRecord
         type_map.lookup(sql_type)
       end
 
+      def column_name_for_operation(operation, node) # :nodoc:
+        node.to_sql
+      end
+
       protected
 
       def initialize_type_map(m) # :nodoc: