From 6cf3b6f5cf0cc3b11e86e511ec5201999913286f Mon Sep 17 00:00:00 2001 From: Mariusz Felisiak Date: Mon, 2 Dec 2019 07:57:19 +0100 Subject: [2.2.x] Fixed #30953 -- Made select_for_update() lock queryset's model when using "self" with multi-table inheritance. Thanks Abhijeet Viswa for the report and initial patch. Backport of 0107e3d1058f653f66032f7fd3a0bd61e96bf782 from master --- docs/ref/models/querysets.txt | 8 ++++++++ docs/releases/2.2.8.txt | 6 ++++++ 2 files changed, 14 insertions(+) (limited to 'docs') diff --git a/docs/ref/models/querysets.txt b/docs/ref/models/querysets.txt index 3ccd5958fd..f23d4bc598 100644 --- a/docs/ref/models/querysets.txt +++ b/docs/ref/models/querysets.txt @@ -1696,6 +1696,14 @@ specify the related objects you want to lock in ``select_for_update(of=(...))`` using the same fields syntax as :meth:`select_related`. Use the value ``'self'`` to refer to the queryset's model. +.. admonition:: Lock parents models in ``select_for_update(of=(...))`` + + If you want to lock parents models when using :ref:`multi-table inheritance + `, you must specify parent link fields (by default + ``_ptr``) in the ``of`` argument. For example:: + + Restaurant.objects.select_for_update(of=('self', 'place_ptr')) + You can't use ``select_for_update()`` on nullable relations:: >>> Person.objects.select_related('hometown').select_for_update() diff --git a/docs/releases/2.2.8.txt b/docs/releases/2.2.8.txt index 4d8f9869c5..3c5eb5c754 100644 --- a/docs/releases/2.2.8.txt +++ b/docs/releases/2.2.8.txt @@ -17,3 +17,9 @@ Bugfixes * Fixed a regression in Django 2.2.1 that caused a crash when migrating permissions for proxy models with a multiple database setup if the ``default`` entry was empty (:ticket:`31021`). + +* Fixed a data loss possibility in the + :meth:`~django.db.models.query.QuerySet.select_for_update()`. When using + ``'self'`` in the ``of`` argument with :ref:`multi-table inheritance + `, a parent model was locked instead of the + queryset's model (:ticket:`30953`). -- cgit v1.3