diff --git a/demos/init-db.php b/demos/init-db.php
index 5b87842b76..519d04cd32 100644
--- a/demos/init-db.php
+++ b/demos/init-db.php
@@ -36,13 +36,15 @@ protected function isAllowDbModifications(): bool
 
     public function atomic(\Closure $fx)
     {
-        $eRollback = new \Exception('Prevent modification');
+        $eRollback = !$this->getModel(true)->getPersistence()->getConnection()->inTransaction()
+            ? new \Exception('Prevent modification')
+            : null;
         $res = null;
         try {
             parent::atomic(function () use ($fx, $eRollback, &$res) {
                 $res = $fx();
 
-                if (!$this->isAllowDbModifications()) {
+                if ($eRollback !== null && !$this->isAllowDbModifications()) {
                     throw $eRollback;
                 }
             });