Change BaseDatabaseFeatures.has_case_insensitive_like to False

[Tim Graham]

It seems that a better default for this feature would be False, as of the built-in backends, only SQLite uses True. In addition, all three of the databases I've built third-party backends for (Cloud Spanner, CockroachDB, Snowflake) all use False. Of course, a mention in the release notes that the default is changed is still appropriate.

[Chinmoy]

I was going through the code and after changing the value to False, one of the tests seemed to fail.

   def test_ticket_16731_startswith_lookup(self):
        Employee.objects.create(firstname="John", lastname="Doe")
        e2 = Employee.objects.create(firstname="Jack", lastname="Jackson")
        e3 = Employee.objects.create(firstname="Jack", lastname="jackson")
        self.assertSequenceEqual(
            Employee.objects.filter(lastname__startswith=F('firstname')),
            [e2, e3] if connection.features.has_case_insensitive_like else [e2]
        )

with the error AssertionError: Sequences differ: <QuerySet [<Employee: Jack Jackson>, <Employee: Jack jackson>]> != [<Employee: Jack Jackson>].
I don't understand why the query filter returns <QuerySet [<Employee: Jack Jackson>, <Employee: Jack jackson>]> when the default value of has_case_insensitive_like is set to False? @Mariusz Felisiak any suggestion on this?

[Tim Graham]

You should add has_case_insensitive_like = True to the sqlite3 backend (and remove the now unneeded has_case_insensitive_like = False from the others).

[Tim Graham]

​PR

[GitHub <noreply@…>]

In 073b7b59:

Fixed #33228 -- Changed value of BaseDatabaseFeatures.has_case_insensitive_like to False.