diff --git a/digitalmeasures_migrate.install b/digitalmeasures_migrate.install
index 1ec1b04..24c7919 100644
--- a/digitalmeasures_migrate.install
+++ b/digitalmeasures_migrate.install
@@ -39,7 +39,7 @@ function digitalmeasures_migrate_schema() {
         'size' => 'big',
       ],
     ],
-    'primary key' => ['id'],
+    'primary key' => ['id', 'userId'],
     'indexes' => [
       'dm_id_site' => ['id', 'category'],
       'dm_id_user' => ['id', 'userId'],