diff --git a/src/aphront/storage/connection/AphrontDatabaseConnection.php b/src/aphront/storage/connection/AphrontDatabaseConnection.php
--- a/src/aphront/storage/connection/AphrontDatabaseConnection.php
+++ b/src/aphront/storage/connection/AphrontDatabaseConnection.php
@@ -11,6 +11,7 @@
   private $readOnly;
   private $queryTimeout;
   private $locks = array();
+  private $lastActiveEpoch;
 
   abstract public function getInsertID();
   abstract public function getAffectedRows();
@@ -20,6 +21,15 @@
   abstract public function close();
   abstract public function openConnection();
 
+  final public function setLastActiveEpoch($epoch) {
+    $this->lastActiveEpoch = $epoch;
+    return $this;
+  }
+
+  final public function getLastActiveEpoch() {
+    return $this->lastActiveEpoch;
+  }
+
   public function queryData($pattern/* , $arg, $arg, ... */) {
     $args = func_get_args();
     array_unshift($args, $this);
diff --git a/src/xsprintf/queryfx.php b/src/xsprintf/queryfx.php
--- a/src/xsprintf/queryfx.php
+++ b/src/xsprintf/queryfx.php
@@ -3,6 +3,8 @@
 function queryfx(AphrontDatabaseConnection $conn, $sql /* , ... */) {
   $argv = func_get_args();
   $query = call_user_func_array('qsprintf', $argv);
+
+  $conn->setLastActiveEpoch(time());
   $conn->executeRawQuery($query);
 }