diff --git a/php/model/DatabaseInitializer.php b/php/model/DatabaseInitializer.php
index de05e02..573d43e 100644
--- a/php/model/DatabaseInitializer.php
+++ b/php/model/DatabaseInitializer.php
@@ -62,6 +62,8 @@ class DatabaseInitializer {
                 $availableEmails = $initializer->seedDummyUsers($db);
                 $initializer->seedDummyArticles($db, $availableEmails);
 
+                unset($db);
+
             } catch (PDOException $e) {
                 throw new RuntimeException("internal-error");
             }