diff --git a/migration/18.04/migratePriorities.php b/migration/18.04/migratePriorities.php
index d43b5b1e53d29612e06e0b9ec5e45ad01e2b8c0d..2945e7d7f71af9bf48cfc1d158d241d048f99fc1 100644
--- a/migration/18.04/migratePriorities.php
+++ b/migration/18.04/migratePriorities.php
@@ -46,9 +46,7 @@ foreach ($customs as $custom) {
             }
         }
 
-        if (!empty($db)) {
-            $db->reset();
-        }
+        \SrcCore\models\DatabasePDO::reset();
 
         $db = new \SrcCore\models\DatabasePDO(['customId' => $custom]);
         foreach ($priorities as $key => $priority) {
diff --git a/migration/18.10/migrateConvertedPdf.php b/migration/18.10/migrateConvertedPdf.php
index 8e32d1e6e59d598b6bc534dfbe8a5b6e8126df1f..bbaf8314a09f08bc2e26171a8e1a0b8c8e2f0dd5 100644
--- a/migration/18.10/migrateConvertedPdf.php
+++ b/migration/18.10/migrateConvertedPdf.php
@@ -15,9 +15,7 @@ foreach ($customs as $custom) {
         continue;
     }
 
-    if (!empty($db)) {
-        $db->reset();
-    }
+    \SrcCore\models\DatabasePDO::reset();
 
     $db = new \SrcCore\models\DatabasePDO(['customId' => $custom]);
 
diff --git a/src/core/models/DatabasePDO.php b/src/core/models/DatabasePDO.php
index 12bda566d64f70f54198caf840bf9d68889cf3f4..b117e807a1e0f94e4e5c1d8a332002276ed18f4d 100755
--- a/src/core/models/DatabasePDO.php
+++ b/src/core/models/DatabasePDO.php
@@ -191,7 +191,7 @@ class DatabasePDO
         return ['where' => $where, 'limit' => $limit];
     }
 
-    public function reset()
+    public static function reset()
     {
         self::$pdo = null;
         self::$preparedQueries = [];