The previous logic was systematically attempting to retrieve last_insert_id
even for models without an AutoField primary key when they had a GeneratedField
on backends that can't return columns from INSERT.
The issue affected MySQL, SQLite < 3.35, and Oracle when the use_returning_into
option was disabled and could result in either crashes when the non-auto
primary key wasn't an IntegerField subclass or silent misassignment of bogus
insert ids (0 or the previous auto primary key insert value) to the first
defined generated field value.
Regression in d9de74141e8a920940f1b91ed0a3ccb835b55729.
This is a long standing issue, however it caused a crash of
GeneratedFields for all output fields that have backend-specific
converters when the RETURNING clause is not supported
(MySQL and SQLite < 3.35).
That's why severity was exacerbated.
Thanks Adam Johnson and Paolo Melchiorre for reviews.
Co-Authored-By: Lily Foote <code@lilyf.org>
Co-Authored-By: Mariusz Felisiak <felisiak.mariusz@gmail.com>
