2 files changed, 18 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
index b5ddef32af..eab61085e3 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_specification.rb
@@ -114,9 +114,15 @@ module ActiveRecord
 
     # Set the connection for the class.
     def self.connection=(spec)
-      raise ConnectionNotEstablished unless spec
-      conn = self.send(spec.adapter_method, spec.config)
-      active_connections[self] = conn
+      if spec.kind_of?(ActiveRecord::ConnectionAdapters::AbstractAdapter)
+        active_connections[self] = spec
+      elsif spec.kind_of?(ConnectionSpecification)
+        self.connection = self.send(spec.adapter_method, spec.config)
+      elsif spec.nil?
+        raise ConnectionNotEstablished
+      else
+        establish_connection spec
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index 90dc951b6d..c45454eacc 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -90,6 +90,15 @@ module ActiveRecord
           end
         end
       end
+
+      def default_sequence_name(table, column)
+        nil
+      end
+
+      # Set the sequence to the max value of the table's column.
+      def reset_sequence!(table, column, sequence = nil)
+        # Do nothing by default.  Implement for PostgreSQL, Oracle, ...
+      end
     end
   end
 end