如何修復django中的遷移錯誤（NOT NULL約束失敗）？

Question

您好，感謝您的寶貴時間

現狀：

我需要在我的Django模型添加一個新的領域

領域

status_of_lieman = models.BooleanField(default=False, verbose_name="Course status") 

Makemigratios去很好，但是當我嘗試遷移我得到錯誤：

Running migrations: 
    Applying faceset.0077_course_status_of_lieman...Traceback (most recent call last): 
    File "C:\python35\lib\site-packages\django\db\backends\utils.py", line 64, in execute 
    return self.cursor.execute(sql, params) 
    File "C:\python35\lib\site-packages\django\db\backends\sqlite3\base.py", line 323, in execute 
    return Database.Cursor.execute(self, query, params) 
sqlite3.IntegrityError: NOT NULL constraint failed: faceset_course.status_of_lieman 

The above exception was the direct cause of the following exception: 

Traceback (most recent call last): 
    File "C:\Program Files (x86)\JetBrains\PyCharm 5.0.4\helpers\pycharm\django_manage.py", line 41, in <module> 
    run_module(manage_file, None, '__main__', True) 
    File "C:\python35\lib\runpy.py", line 182, in run_module 
    return _run_module_code(code, init_globals, run_name, mod_spec) 
    File "C:\python35\lib\runpy.py", line 96, in _run_module_code 
    mod_name, mod_spec, pkg_name, script_name) 
    File "C:\python35\lib\runpy.py", line 85, in _run_code 
    exec(code, run_globals) 
    File "E:/lieman\manage.py", line 10, in <module> 
    execute_from_command_line(sys.argv) 
    File "C:\python35\lib\site-packages\django\core\management\__init__.py", line 353, in execute_from_command_line 
    utility.execute() 
    File "C:\python35\lib\site-packages\django\core\management\__init__.py", line 345, in execute 
    self.fetch_command(subcommand).run_from_argv(self.argv) 
    File "C:\python35\lib\site-packages\django\core\management\base.py", line 348, in run_from_argv 
    self.execute(*args, **cmd_options) 
    File "C:\python35\lib\site-packages\django\core\management\base.py", line 399, in execute 
    output = self.handle(*args, **options) 
    File "C:\python35\lib\site-packages\django\core\management\commands\migrate.py", line 200, in handle 
    executor.migrate(targets, plan, fake=fake, fake_initial=fake_initial) 
    File "C:\python35\lib\site-packages\django\db\migrations\executor.py", line 92, in migrate 
    self._migrate_all_forwards(plan, full_plan, fake=fake, fake_initial=fake_initial) 
    File "C:\python35\lib\site-packages\django\db\migrations\executor.py", line 121, in _migrate_all_forwards 
    state = self.apply_migration(state, migration, fake=fake, fake_initial=fake_initial) 
    File "C:\python35\lib\site-packages\django\db\migrations\executor.py", line 198, in apply_migration 
    state = migration.apply(state, schema_editor) 
    File "C:\python35\lib\site-packages\django\db\migrations\migration.py", line 123, in apply 
    operation.database_forwards(self.app_label, schema_editor, old_state, project_state) 
    File "C:\python35\lib\site-packages\django\db\migrations\operations\fields.py", line 62, in database_forwards 
    field, 
    File "C:\python35\lib\site-packages\django\db\backends\sqlite3\schema.py", line 221, in add_field 
    self._remake_table(model, create_fields=[field]) 
    File "C:\python35\lib\site-packages\django\db\backends\sqlite3\schema.py", line 189, in _remake_table 
    self.quote_name(model._meta.db_table), 
    File "C:\python35\lib\site-packages\django\db\backends\base\schema.py", line 110, in execute 
    cursor.execute(sql, params) 
    File "C:\python35\lib\site-packages\django\db\backends\utils.py", line 79, in execute 
    return super(CursorDebugWrapper, self).execute(sql, params) 
    File "C:\python35\lib\site-packages\django\db\backends\utils.py", line 64, in execute 
    return self.cursor.execute(sql, params) 
    File "C:\python35\lib\site-packages\django\db\utils.py", line 95, in __exit__ 
    six.reraise(dj_exc_type, dj_exc_value, traceback) 
    File "C:\python35\lib\site-packages\django\utils\six.py", line 685, in reraise 
    raise value.with_traceback(tb) 
    File "C:\python35\lib\site-packages\django\db\backends\utils.py", line 64, in execute 
    return self.cursor.execute(sql, params) 
    File "C:\python35\lib\site-packages\django\db\backends\sqlite3\base.py", line 323, in execute 
    return Database.Cursor.execute(self, query, params) 
django.db.utils.IntegrityError: NOT NULL constraint failed: faceset_course.status_of_lieman 

我該如何解決這個問題？我知道，我可以刪除所有遷移並執行此操作。但是我不能這麼做，因爲我會刪除這個模型的所有信息。

Answer 1

您的遷移可能不會爲您的數據庫中將創建此對象的對象設置值。您可能必須刪除最後一個遷移文件，在您的模型字段中設置null = True並再次運行遷移。