1 files changed, 20 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index f48b107a2a..6924bb7e6f 100755..100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -51,6 +51,13 @@ module ActiveRecord
         true
       end
 
+      # Does this adapter support DDL rollbacks in transactions?  That is, would
+      # CREATE TABLE or ALTER TABLE get rolled back by a transaction?  PostgreSQL,
+      # SQL Server, and others support this.  MySQL and others do not.
+      def supports_ddl_transactions?
+        false
+      end
+
       # Should primary key values be selected from their corresponding
       # sequence before the insert statement?  If true, next_sequence_value
       # is called before each insert to set the record's primary key.
@@ -118,6 +125,19 @@ module ActiveRecord
         @connection
       end
 
+      def open_transactions
+        @open_transactions ||= 0
+      end
+
+      def increment_open_transactions
+        @open_transactions ||= 0
+        @open_transactions += 1
+      end
+
+      def decrement_open_transactions
+        @open_transactions -= 1
+      end
+
       def log_info(sql, name, runtime)
         if @logger && @logger.debug?
           name = "#{name.nil? ? "SQL" : name} (#{sprintf("%f", runtime)})"