diff --git a/core/Entity/Site/Node.php b/core/Entity/Site/Node.php
index 99b63e9..208e201 100644
--- a/core/Entity/Site/Node.php
+++ b/core/Entity/Site/Node.php
@@ -125,6 +125,7 @@ class Node implements EntityInterface
 
     /**
      * @ORM\ManyToOne(targetEntity=Node::class, inversedBy="aliasNodes")
+     * @ORM\JoinColumn(nullable=true, onDelete="SET NULL")
      */
     protected $aliasNode;