, null=True)
"""String for representing the Model object.""", null=True)
parent = models.ForeignKey('self', blank=True, related_name='child', help_text='Parentdel T
在最新的Django (2.2)中,当我向这样的模型添加一个新字段时:Django为MySQL运行以下命令:ALTER TABLE `app_mymodel` ADD COLUMN `new_field` boolDEFAULT b'0' NOT NULL;
ALTER TABLE `app_mymodel` ALTER