diff --git a/bin/database.py b/bin/database.py
index acf466b980fef972f2103d97eee53941f0044951..f50ae097855815901dd721f0468e1c42ec949775 100755
--- a/bin/database.py
+++ b/bin/database.py
@@ -610,7 +610,7 @@ def upgrade_to_21():
 
                     updated_files.append(file_)
                 if update.get('$set'):
-                    update['$set']['files': updated_files]
+                    update['$set']['files'] =  updated_files
                 else:
                     update['$set'] = {'files': updated_files}