Django 1.11.16 release notes — Django documentation
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Django/docs/2.2.x/releases/1.11.16
Django 1.11.16 release notes
October 1, 2018
Django 1.11.16 fixes a data loss bug in 1.11.15.
Bugfixes
- Fixed a race condition in
QuerySet.update_or_create()
that could result in data loss (:ticket:`29499`).