diff --git a/frappe/model/base_document.py b/frappe/model/base_document.py
index 337dd9dbf2..7ecd8a24b5 100644
--- a/frappe/model/base_document.py
+++ b/frappe/model/base_document.py
@@ -358,6 +358,11 @@ class BaseDocument(object):
 
 		self.run_method('on_change')
 
+	def update_modified(self):
+		'''Update modified timestamp'''
+		self.set("modified", now())
+		frappe.db.set_value(self.doctype, self.name, 'modified', self.modified, update_modified=False)
+
 	def _fix_numeric_types(self):
 		for df in self.meta.get("fields"):
 			if df.fieldtype == "Check":
diff --git a/frappe/model/db_query.py b/frappe/model/db_query.py
index 543979a343..9eb9811f34 100644
--- a/frappe/model/db_query.py
+++ b/frappe/model/db_query.py
@@ -428,7 +428,7 @@ class DatabaseQuery(object):
 						f.split()[0].strip(), f.split()[1].strip()) for f in meta.sort_field.split(',')])
 				else:
 					sort_field = meta.sort_field or 'modified'
-					sort_order = meta.sort_order or 'desc'
+					sort_order = (meta.sort_field and meta.sort_order) or 'desc'
 
 					args.order_by = "`tab{0}`.`{1}` {2}".format(self.doctype, sort_field or "modified", sort_order or "desc")