fixing orientdb query

app/repositories/orient_db/user_repository.rb

@@ -11,7 +11,7 @@ module OrientDb
     end
 
     def destroy_graph_node(user)
-      connection.command sprintf("destroy vertex User WHERE p_id = %d", user.id)
+      connection.command sprintf("delete vertex User WHERE p_id = %d", user.id)
     end
 
     def get_graph_id(user)