diff --git a/redirect.install b/redirect.install
index d9e6843..be130b7 100644
--- a/redirect.install
+++ b/redirect.install
@@ -95,6 +95,7 @@ function redirect_schema() {
     ),
     'indexes' => array(
       'expires' => array('type', 'access'),
+      'source_language' => array('source', 'language'),
     ),
   );
 
@@ -180,3 +181,12 @@ function redirect_update_5() {
     db_add_index('redirect', 'expires', array('type', 'access'));
   }
 }
+
+/**
+ * Add index on redirect table
+ */
+function redirect_update_6($context) {
+  if (!db_index_exists('redirect', 'source_language')) {
+    db_add_index('redirect', 'source_language', array('source', 'language'));
+  }
+}