id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
23678	Database default not removed if default=None	Tim Graham	nobody	If you have a model field like `models.CharField(max_length=255, blank=True, null=True, default=None)`, you will end up something like `varchar(255) DEFAULT NULL` with MySQL. The `DEFAULT NULL` should be dropped but isn't due to the `field.default is not None` check here: https://github.com/django/django/blob/8d6e1afe0be0570253a508f43e2ef89ae640984e/django/db/backends/schema.py#L382	Bug	closed	Migrations	1.7	Release blocker	worksforme			Accepted	0	0	0	0	0	0