diff --git a/core/modules/dblog/dblog.install b/core/modules/dblog/dblog.install
index 23f85ba..55e36d5 100644
--- a/core/modules/dblog/dblog.install
+++ b/core/modules/dblog/dblog.install
@@ -85,6 +85,7 @@ function dblog_schema() {
     'indexes' => array(
       'type' => array('type'),
       'uid' => array('uid'),
+      'timestamp' => array('timestamp'),
     ),
   );
 
diff --git a/core/modules/node/node.install b/core/modules/node/node.install
index a6d0b7a..43404e0 100644
--- a/core/modules/node/node.install
+++ b/core/modules/node/node.install
@@ -420,6 +420,7 @@ function node_schema() {
     'primary key' => array('uid', 'nid'),
     'indexes' => array(
       'nid' => array('nid'),
+      'timestamp' => array('timestamp'),
     ),
   );