データベース・テーブルの作成中にエラーが発生しました

You are trying to change the nullable field 'slug' on post to non-nullable without a default; we can't do that
(the database needs something to populate existing rows).
Please select a fix:
 1) Provide a one-off default now (will be set on all existing rows with a null value for this column)
 2) Ignore for now, and let me handle existing rows with NULL myself (e.g. because you added a RunPython or RunSQL
 operation to handle NULL values in a previous data migration)
 3) Quit, and let me add a default in models.py
Select an option:

CharField(default = '')
CharField(null = True)

DROP TABLE 테이블이름;

SELECT * FROM django_migrations;

delete from django_migrations where app = 'app이름';